FOUTA DJALLON HIGHLAND WATER ATLAS The Water Tower of West Africa June 2017 About the Water Global Practice About CIWA Launched in 2014, the Word Bank Group’s Water Global Prac- The Cooperation in International Waters in Africa (CIWA) was tice brings together fi nancing, knowledge, and implementation established in 2011 and represents a partnership between the in one platform. By combining the Bank’s global knowledge with World Bank, its African partners, the European Commission, and country investments, this model generates more fi repower for the governments of Denmark, Norway, Sweden, the Netherlands, transformational solutions to help countries grow sustainably. and the United Kingdom. CIWA supports riparian governments in Sub-Saharan Africa to unlock the potential for sustainable and Please visit us at www.worldbank.org/water or follow us on Twitter inclusive growth, climate resilience, and poverty reduction by at @WorldBankWater. addressing constraints to cooperative management and develop- ment of international waters. www.worldbank.org/africa/ciwa FOUTA DJALLON HIGHLAND WATER ATLAS PREFACE Looking at the West African water resources and their transboun- was undertaken, to examine their nature and how it differs from the The Water Atlas of Fouta Djallon highland is an initial basis for sharing dary management, it is evident that the Fouta Djallon highland have other surrounding highlands. A study was also carried out to deter- knowledge among the stakeholders of countries that are interested a special and important role to play, which extends well beyond mine the basins and sub-basins. This has been supplemented by a by, or dependent upon, the water of these Highlands. It supplements Central Guinea. The Highlands are the source of many international summary of land use and climate characteristics. Finally, its water re- the historical work of the Regional Program for Integrated Develop- rivers, which include the Senegal, Gambia, Niger, Rio Corubal, and sources are presented as an exhaustive synthesis of the hydrological ment (RPID) of the Fouta Djallon highland, which was started by the the Great and Little Scarcies Rivers. Eight countries (The Gambia, Gui- regimes of the main rivers originating in the Fouta Djallon highland, African Union in 1981. Producing this document also revealed how nea, Guinea-Bissau, Mali, Mauritania, Niger, Sierra Leone and Sene- based on current knowledge. much work remains to be done in terms of knowledge, but also in gal) are thus directly or indirectly affected by these Highlands’ water terms of managing and capitalizing upon this information over the The subsequent sections provide a view of the main human resources. Preservation and balance in the Fouta Djallon highland are upcoming years. The importance of water resources for populations characteristics and water use in the Fouta Djallon highland, with therefore key issues for the entire sub-region. However, the Fouta that depend upon the Fouta Djallon highland should encourage us the related constraints, issues or challenges that have been assessed Djallon highland have never really been studied through an inte- to continue our efforts with regard to studies and publications that or that will need special attention in the future. Based upon acces- grated approach, even though they are the focus of many concerns. will reconcile socio-economic development with the preservation sible data, these sections also address the areas that are dependent The Fouta Djallon Water Resources Atlas, produced by ECOWAS/ of the Highlands in the context of the climate and demographic on the Fouta Djallon highland and, more generally, on the conditions WRCC with funding support from the World Bank, is a monographic challenges that characterize the sub-region. at the heart of Fouta Djallon highland. synthesis of the Fouta Djallon highland, which aims to provide a com- ECOWAS/WRCC is a full and willing participant in this process and prehensive picture of both its physical components and its water We wish to emphasize that this atlas is based upon data and thus remains at the disposal of representatives from the countries resources, including their uses and the roles they play - more specifi- knowledge that often come from a distant past, such as hydro-cli- that share the water resources of these Highlands. By making the Wa- cally their environmental roles. matic monitoring data which, in some cases, dates back to the 1920s, ter Atlas of the Fouta Djallon highland available to decision-makers and on the results of studies by D. Orange on the Hydro-Climatolo- The first sections of the atlas present the physical properties and stakeholders in these countries, our intention is to provide rea- gy of the Fouta Djallon (1990), by Y. L’Hôte and G. Mahé on Rainfall of the Fouta Djallon highland and attempt to clarify the multiple ders with knowledge and support, and we hope that everyone will in West Africa (1995), or by Y. Boulvert on the Morphopedology of definitions found in the literature. For this specific objective, a study greatly benefit from this document. Guinea (2003). describing the topographic contours of the Fouta Djallon highland IBRAHIM BABATUNDÉ WILSON Director of the ECOWAS Water Resources Coordination Centre (WRCC) 3 FIGURES FOUTA DJALLON HIGHLAND Natural region of Central Guinea in Guinea 4 countries directly concerned : Guinea, Mali, Senegal, Sierra Leone AREA 47 000 km² MAIN ASSOCIATED HIGHLANDS Guinean Dorsal: 89 000 km² Coastal Guinea highland: 29 000 km² Siguirini-Baléa region highland: 6 000 km² Manding mounts: 24 000 km² RIVER BASINS OF THE AREA 20 river basins 15 transboundary basins including Senegal, Gambia Niger, Rio-Corubal, Great scarcies and Little Scarcies CONTRIBUTION & ACKNOWLEDGMENTS THE FOLLOWING PEOPLE HAVE PROVIDED CONTRIBUTIONS TO THIS ATLAS ECOWAS-WRCC ADVISORY OPINION OF THE VALIDATION AND STEERING COMMITTEE Ibrahim Babatundé Wilson, Mahamane Dédéou Touré, Janvier Ba- zoun, Ibrahim Babatundé Wilson Mohamadou Diallo, FAO Regional Fouta Djallon Highland Inte- grated Natural Resources Management Project; Mariama Dandio WORLD BANK Diallo, IUCN; Almami Danpha, African Union Commission Pierrick Fraval, Sylvestre Béa, Thierry Davy, Fidele Tchossi Moutoua- LEAD AUTHORS ma Axel Aurouet, Géohyd / Anteagroup, France VALIDATION AND STEERING COMMITTEE FOR THE STUDY Luc Ferry, Anteagroup, France The Gambia, Yusupha Bojang, Director of Hydraulics, DoWR Gérard Cougny, Anteagroup, France The Gambia, Fatou John, RPID-FDH Focal Point, DoWR MAPPING Guinea, Atigou Baldé, RPID-FDH Focal Point, DNH Guinea, Mandiou Condé, Director of Hydraulics, DNH Modeling & spatialization team from Anteagroup’s Research and Innovation Division Guinea Bissau, Mauricio Correia de Matos, RPID-FDH Focal Point, Ministry of Natural Resources LAYOUT Mali, Djoouro Bocoum, Director of Hydraulics, DNH Jérôme Falala, Orléans, France. Mali, Toumany Dembele, RPID-FDH Focal Point, MEDD Mauritania, Maloun Dine Maouloud, RPID-FDH Focal Point, MEDD ECOWAS - WRCC also wishes to specifically thank all the institutions involved with water and the environment in all 8 member countries of the RPID Fouta Djallon Highland, as well as all the technical teams of the transboundary basin organizations, for their support during the whole Niger, Abdou Moumouni Moussa, Director of Hydraulics, DGRE project. Senegal, Niokor Ndour, Director of Hydraulics, DGPRE Senegal, Mortalla Niass, RPID-FDH Focal Point, MEDD © 2017 International Bank for Reconstruction and Development / The World Bank 1818 H Street NW, Washington, DC 20433 Telephone: 202-473-1000; Internet: www.worldbank.org Sierra Leone, Ishmail Kamara, Director of Hydraulics, MoWR This work is a product of the staff of The World Bank with external contributions. The findings, interpretations, and conclusions expressed in this work do not necessarily reflect the views of The World Bank, its Board of Executive Directors, or the governments they represent. NBA, Didier Zinsou, Niger Basin Authority, NBA The World Bank does not guarantee the accuracy of the data included in this work. The boundaries, colors, denominations, and other information shown on any map in this work do not imply any judgment on the part of The World Bank concerning the legal status of any territory or the endorsement or acceptance of such boundaries. OMVG, Nassirou Condetto Touré, Gambia River Basin Develop- Rights and Permissions ment Authority, OMVG The material in this work is subject to copyright. Because The World Bank encourages dissemination of its knowledge, this work may be reproduced, in whole or in part, for noncommercial purposes as long as full OMVS, Alpha Oumar Baldé, Senegal River Basin Development Au- attribution to this work is given. Please cite the work as follows: World Bank 2017. Water Atlas of Fouta Djallon Highland. World Bank, Washington, DC. Any queries on rights and licenses, including subsidiary rights, should be addressed to World Bank thority, OMVS Publications, The World Bank Group, 1818 H Street NW, Washington, DC 20433, USA; fax: 202-522-2625; e-mail:†pubrights @ worldbank.org. Cover photo: © AXEL AUROUET Cover design: © JÉRÔME FALALA 5 TABLE OF CONTENTS PREAMBLE AT THE ORIGIN OF THE FOUTA DJALLON 10 THE PHYSICAL ENVIRONMENT OF FOUTA DJALLON AND ITS EXTENDED AREA TOPOGRAPHY AND PHYSICAL DEFINITION OF THE FOUTA DJALLON HIGHLAND AND THE SURROUNDING HIGHLANDS 16 FOUTA DJALLON RIVERS AND RIVER BASINS 20 GEOLOGY 28 LAND COVER IN THE FOUTA DJALLON HIGHLAND AND ITS EXTENDED ZONES 30 MAJOR CLIMATE FEATURES 34 HISTORICAL TREND IN RAINFALL AND CURRENT TRENDS 40 SUMMARY OF PHYSICAL LANDSCAPE 42 WATER RESOURCES OF FOUTA DJALLON AND ITS EXTENDED AREA HYDROLOGICAL REGIMES OF THE FOUTA DJALLON RIVERS 46 HYDROGEOLOGY AND GEOCHEMISTRY 60 SUMMARY ON WATER RESOURCES 62 WATER USES IN THE FOUTA DJALLON HIGHLAND DEMOGRAPHY AND WATER REQUIREMENTS 66 AGRICULTURE 72 HYDROELECTRIC POWER POTENTIAL OF FOUTA DJALLON 80 MINING 84 SUMMARY ON WATER USES 88 WATER CHALLENGES IN THE FOUTA DJALLON HIGHLAND REMARKABLE NATURAL SPACES AND SPECIES 92 CLIMATE CHANGE AND ADAPTATION 94 CONFLICTS LINKED TO WATER 98 THE FOUTA DJALLON HIGHLAND’ GOUVERNANCE 100 SUMMARY OF THE ISSUES 106 CONCLUSIONS OF THE ATLAS 7 PREAMBLE FOUTA DJALLON HIGHLAND WATER ATLAS AN INFLUENCE ON ALL OF WEST AFRICA This chapter introduces the Fouta Djallon highland, its various delimitations or interpretations and its role as «water tower» of West Africa. 9 AT THE ORIGIN OF FOUTA DJALLON THE FOUTA DJALLON, A NATURAL AND CULTURAL MOUNTAINOUS AREA LOCATED IN CENTRAL GUINEA, IS UNANIMOUSLY RECOGNIZED AS «THE WATER TOWER OF WEST AFRICA», WITH REFERENCE TO THE MANY INTERNATIONAL RIVERS WHICH HAVE THEIR ORIGIN THERE. HOWEVER, IT IS SUBJECT TO MULTIPLE DELINEATIONS. THE MULTIPLE DELINEATIONS OF FOUTA river - Tinkisso - Sankarani - Milo - Niandan - meet), the Northern part Koïn, Kolladé, Fadé Hadji, Timbi Touni, Timbi Madina, Bani, Massi and of Sierra Leone corresponding to the upstream part of the Great and Akolémadji) (Bouillet, 1893 – map 1). As a unique landscape, Fouta DJALLON HIGHLAND Little Scarcies rivers, the Eastern part of Guinea-Bissau corresponding Djallon is therefore also at the crossroads between a significant ethnic Fouta Djallon is a powerful name which immediately invoke Guinea’s to the upstream part of the Koliba - Rio Corubal and the Kolda-Tam- and cultural history. topography. However, although it is a recognisable and a well-known bacounda sector in Senegal, including the upstream sectors of the natural entity, there is no precise geographical definition for Fouta Koulountou river and the Gambia river before they enter The Gambia. Djallon (Orange 1990). There are currently several geographic defi- All Fouta Djallon boundaries are shown on map 2. nitions, with its actual definition remaining unclear. Whilst certain geo- There are therefore several interpretations of the Fouta Djallon morphologists associate the Fouta Djallon highland with the Central highland which coexist in different literature, differences which some- Guinea topography, others associate it more with the Guinean Dorsal times create confusion regarding its actual definition. This confusion in Upper Guinea and Forest area of Guinea (map 1). There are also is accentuated by the origin of the highland’s name. Etymologically, highlands on the south side of Guinea, which, depending on specific Fouta Djallon means “Country of the Djalonkés”, Fulani farmers - giving interpretations, may or may not be associated with the Fouta Djallon an anthropological emphasis to Fouta Djallon. This emphasis is sup- highland. In this water atlas, a comprehensive chapter on the sector’s ported historically with the existence of a State of Fouta Djallon, which topography provides an initial definition between those different sec- was created around the mid-18th century under the influence of a tors whilst offering a more specific topographical definition of these Foula leader which included eleven provinces (Timbo, Labé, Kolen, landscape features. In addition to these topographical approaches, the FAO also offers a geographical definition of Fouta Djallon which covers a larger zone Régions naturelles Map 1 > Natural de Guinée region of Guinea including part of the Guinean Dorsal, the Coastal Guinea Highland, -15.0 -10.0 BAMAKO the extension of the highland from North-Eastern Guinea to Mali, as well as an extended area towards Guinea-Bissau and Southern Sene- CENTRAL GUINEA 12.0 gal. Based on different topographic and climate approaches, and river BISSAU basins limit, this definition of Fouta Djallon by the FAO goes beyond Labé the “natural” limits of the highland itself and covers an extended area Timbi Madina Koin Bani around the Fouta Djallon highland which is consistent with several na- Kolen Massi tural criteria. Fadé Hadji UPPER GUINEA C O A S TA L Timbo Finally, as part of the Fouta Djallon highland’ regional integrated de- GUINEA velopment programme (FDH-RPID) covering 8 countries (The Gam- 10.0 bia, Guinea, Guinea-Bissau, Mali, Mauritania, Niger, Senegal, Sierra Leone), two suggested geographical boundaries are proposed. The CONAKRY first definition includes a “restricted” zone completely linked to Gui- nea and mainly based on Guinea prefectures influenced by Fouta Djallon (mainly from a hydrological and topographical point of view). Legend A second, larger definition extends towards Senegal, Guinea-Bissau, FOREST Coastal Guinea FREETOWN GUINEA Sierra Leone and Mali. This second zone, which we will call “the wider Central Guinea extension”, includes the sector of Bakel in Senegal (site where the main 8.0 Upper Guinea tributaries of the Senegal river - Falémé - Bafing - Bakoye - meet), the sector of Markala in Mali (site where the main tributaries of the Niger Forest Guinea Projection latitude - longitude WGS 84 - Géohyd - Created by Géohyd Anteagroup - Luc Ferry & Axel Aurouet 2017 FOUTA DJALLON HIGHLAND WATER ATLAS • PREAMBLE Map 2 > Delineation Délimitation du Fouta Djallon ofmassif du highland, its extension Fouta Djalon, de sesand zones surrounding zones topographic et highlands d’extensions des massifs topographiques environnants Topographic highlands from Luc Ferry 2017 -20.00 -15.00 -10.00 -5.00 SENE GA L M AU R I TA N I A Wider extension zone 15.00 from RPID FDH DAKAR Ex te ns ion zone s SENEGAL Extension zone from FAO BIA GAM E THE GAMBIA M BANJUL LE ER G FA IG N FI N Restcricted extension BA zone from RPID FDH BAMAKO RUBAL GUINEA CO BISSAU MALI Coastal topographic BISSAU highland of Guinea GUINEA Topographic highland Top o gra p hic highla nds of Fouta Djallon A T topographic highland of Siguirini - Baléa region 10.00 L I ES A CONAKRY RC A Banié-Niandan chain SC N Altimetry T Topographic highland of 0m SIERRA I Guinean Dorsal LEONE IVORY COAST 50 m C FREETOWN 200 m Manding mountains and O their extensions to the C 500 m north and the north-west E 700 m YAMOUSSOUKRO A LIBERIA topographic highland of N 1000 m Madinani region 1250 m MONROVIA > 1500 m Projection latitude - longitude WGS 84 - FAO, ECOWAS, RPID-FDH, Géohyd - Topographic highlands from L. Ferry, 2017 - Created by Géohyd Anteagroup - Luc Ferry & Axel Aurouet 2017 11 ORIGIN FOUTA DJALLON OR FOUTA DJALON? Both spellings are used in literature, although Fouta Djallon tends to be used in English literature and Fouta Djalon in French literature. It is usual to find both spellings in the same text, and in the oldest descriptions of Fouta Djallon from the 19th century, the spelling Fouta Djallon was used in French literature Estearn edge of Fouta Djallon nearby Mamou and Dalaba THE WATER TOWER OF WEST AFRICA Whilst the current definition of the Fouta Djallon highland is (OMVS), and the Gambia River Development Authority (OMVG). This Fouta Djallon highland’ Water Atlas aims to present the subject to various interpretations, nevertheless it is unanimously Those river basin organisations also cover the Fouta Djallon highland both from a physical and human point of view, and in- known as the “Water Tower” of West Africa, about the fact that va- highland in their role of managing and planning water resources cludes knowledge acquired over many years. rious transboundary rivers and their tributaries have their sources in the territory. in these highlands. It contains the source of the Gambia River, the The Fouta Djallon highland therefore have an influence which goes source of the Bafing - Falémé - Bakoye complex which form the Se- beyond the limits of the Guinean Dorsal itself, and the population negal river after the Bafing - Bakoye confluence in Mali, the source of a large part of West Africa, through transboundaries river basin, of the Koliba which becomes the Rio Corubal in Guinea-Bissau, the have some sort of connection with this highland (map 4). source of the Kolenté which becomes the Great Scarcies in Sierra Leone, the source of the Kaba and Mongo which become Little Scarcies in Sierra Leone or even the Niger river and its left bank Bassins versants Map 3 > Main deof river basins l’Ouest Guinéen west Africa Guinea tributary, the Tinkisso (map 3). -15.0 -10.0 -5.0 0.0 In all hydrology-related monographs on river basin, the Fouta Djal- NOUAKCHOTT lon highland is highlighted in its role as a “spring” and this aspect ooding area of gives it a key role around water issues for all transboundary river iinner Niger delta basins. As a result, a Fouta Djallon highland’ Regional Integrated Development Programme (FDH-RPID) was established very ear- ly to preserve the highland from damage by bringing together 8 countries dependent on the Fouta Djallon highland’ waters 15.0 DAKAR (The Gambia, Guinea-Bissau, Sierra Leone, Mali, Mauritania, Niger and Senegal). The geographical area covered by these 8 coun- Gambie Sénégal tries, although sometimes partially covered by the Fouta Djallon BANJUL NIAMEY highland’ waters, is therefore defined as the area of influence of BAMAKO the Fouta Djallon highland in different literature. This FDH-RPID Géba OUAGADOUGOU BISSAU project is specifically focused in spring protection (controlling ero- Corubal Niger sion in particular) but also include a biodiversity protection and an Kogon Konkouré evaluation of organic production potential components. Nunez Little Scarcies In shared recognition of its fundamental role in integrated water Fatala 10.0 resources management of river basins (whether transboundary CONAKRY or not), the Fouta Djallon highland is now directly linked to three Great Scarcies transboundaries organisations in the basin which are the Niger FREETOWN Basin Authority (NBA), the Senegal River Development Authority Projection latitude - longitude WGS 84 - Géohyd - Watershed from L. Ferry, 2017 - Created by Géohyd Anteagroup - Luc Ferry & Axel Aurouet 2017 FOUTA DJALLON HIGHLAND WATER ATLAS • PREAMBLE Zone d’in Map 4 > uence Area of du influence of massif duhighland Fouta Djallon Djalon Foutaand et Guinean de la Dorsal onDorsale Guinéenne West African rivers sur les cours d’eau d’Afrique de l’Ouest -20.00 -10.00 0.00 DAKAR BANJUL NIAMEY BAMAKO OUAGADOUGOU BISSAU A 10.00 CONAKRY T ABUJA L A Topographic highland FREETOWN of Fouta Djallon N YAMOUSSOUKRO T I C MONROVIA PORTO NOVO LOME ACCRA O C E Topographic highland of A guinean dorsal N G U I N E A N G U L F Projection latitude - longitude WGS 84 - Géohyd - Topographic highlands from L. Ferry, 2017 - Created by Géohyd Anteagroup - Axel Aurouet, Gérard Cougny & Luc Ferry 2017 13 THE PHYSICAL ENVIRONMENT OF FOUTA DJALLON AND ITS EXTENDED AREA FOUTA DJALLON HIGHLAND WATER ATLAS AN ANCIENT LATERITIC LANDSCAPE This chapter defines in a precise way the delimitation of the various highlands of the area and proposes a clear definition of them. It also deals on watersheds, which it inventories, as well as on land use, geology, geomorphological aspects and climate. 15 TOPOGRAPHY AND PHYSICAL DEFINITION OF THE FOUTA DJALLON HIGHLAND AND THE SURROUNDING HIGHLANDS THE TOPOGRAPHIC MOUNTAIN RANGE OF THE FOUTA DJALLON BREAKS AWAY FROM THE GUINEAN COASTAL MOUNTAINS ON ITS SOUTHERN EDGE AND FROM THE GUINEAN HIGHLANDS ON ITS SOUTHEASTERN FRINGE. DELINEATED BY A 440 M CONTOUR AND WITH A SURFACE AREA OF APPROXIMATELY 47,000 KM², THE TOPOGRAPHIC MOUNTAIN RANGE OF THE FOUTA DJALLON LIES MAINLY ACROSS GUINEA, AND ITS BORDERS REACH MALI, SENEGAL AND SIERRA LEONE. Massifs Map 5 >topographiques duof Topographic highlands secteur the area et andpositionnement des position of altimetry pro ls altimétriques profiles MANY HIGHLANDS AROUND FOUTA DJALLON -25 -20 -15 Nimalo-Konsolon, 418 m Famansa, 785 m -5 14 Mountains in the region, known as the “Water Tower of West Africa”, BANJUL Mali, 1489 m 761 m 3b have been poorly described. As an example, there is a strong confusion 850 m between the Fouta Djallon highland and the Guinean Dorsal. Some BAMAKO 1a Bonmborou, 364 m authors believe that the FDH are a sub-set of the Guinean Dorsal. 1245 m BISSAU Didi, 807 m 12 For others, the Fouta Djallon highland and Guinean Dorsal are two Kondiwel, 369 m 2a separate geographic bodies (Boulvert, 1992; Ninot, 1994). A Séla, 404 m T 716 m Léguétera, 1011 m Yet Orange (1990) mentions that «Although it is a recognizable Lontonkon, 396 m L 2b 1425 m 3a Tougoukoli, 828 m 10 and recognized natural entity»…»There is no clear geographical demarcation of the Fouta Djallon. «. For others, the Fouta Djallon A CONAKRY Legend Gbéria Fotomby / Hérémakono, 489 m 4a highland and the Guinean Highlands are two distinct geographical N Zégoa, 435 m Topographic highland of Fouta Djallon T FREETOWN entities (Boulvert, 1992; Ninot, 1994; Diallo, 2010). In this atlas, the Topographic highland of Guinean Dorsal I C Tembicoundo, 1061 m 8 Fouta Djallon highland and the Guinean Highlands are considered to Coastal highland of Guinea Sounououla, 1147 m be two separate entities. Highland of Siguirini region O 4b 1381 m YAMOUSSOUKRO Manding mounts C The map 5 shows three main groups: the Guinean Dorsal, the Fouta MONROVIA Ouéléba, 1332 m Banié - Niandan chain E 6 Djallon highland and the Guinea coastal highland. Four other smaller A Highland of Madinani region N Karabadougou, 1230 m 1b mountains, both due to their extensions and their altitudes, can also be Luc Ferry, 2017, projection latitude - longitude WGS 84 distinguished: the Manding mounts, the small mountain in the regions of Sigurini/Baléa and Madinani. These four mountains, next to the area Table 1 > Main characteristics of highlands in question, are only briefly described here. Main features of those Minimum Altitude MaximumAltitude Mean Altitude Mean Slope highlands are shown in table 1. Highlands Area (km²) (m) (m) (m) (%) BOUNDARIES BETWEEN FOUTA DJALLON, Guinea coastal 29 000 80 1 188 256 15.5 GUINEAN DORSAL AND COASTAL HIGHLAND highland Guinean Dorsal 89 000 440 1 950 563 12.6 The elevation profile of the water division line (figure 1) separating the Gambia, Senegal and Niger river basins (North-West to North-East) Fouta Djallon from other river basins from the Géba river basin to the Sassandra river 47 000 406 1 538 686 16.3 highland basin (South-East to South-West) helps establish a boundary on this Siguirini/Baléa profile between the Fouta Djallon highland and the Guinean Dorsal. 6 000 400 882 502 13.6 highland To fit the surrounding peaks into the central continuous highland, this limit is located at around 440 m at the Gbéria Fotomby/Hérémakono Manding mounts 24 000 360 785 420 6.6 pass, names of the two villages located respectively in Sierra Leone and Madinani region Guinea. 6 000 420 914 472 9.8 highland Banié Niandan chain (4 000) 859 FOUTA DJALLON HIGHLAND WATER ATLAS • THE PHYSICAL ENVIRONMENT OF FOUTA DJALLON AND ITS EXTENDED AREA Altimetry pro le 1a - 1b 1425 m Gbéria Fotomby / Hérémakono, Sounououla, 1147 m Luc Ferry 2017 1500 Mali, 1489 m 489 m Ouéléba, 1332 m Peak Karabadougou, 1230 m 1300 Pass Tembicoundo, 1061 m Zégoa, 435 m 1100 Tougoukoli, 828 m Alt (m) 900 700 1-b 1-a Distance (km) 500 300 Highland 100 Fouta Djallon Highland Guinean Dorsal of Mandinani region 0 100 200 300 400 500 600 700 800 900 1000 1100 1200 1300 1400 1500 1600 1700 1800 1900 2000 2100 2200 2300 2400 2500 2600 2700 2800 2900 3000 3100 3200 3300 3400 3500 3600 Figure 1 > Altimetry profile and drainage divided line between Fouta Djallon highland, Guinean Dorsal and highland of Madinani region (Profile 1-a 1-b map 5) The Guinea coastal highland on the Atlantic coast cover mountains with an altitude above or equal to 80  m (figure 2). The boundary which differentiates between the Fouta Djallon highland and the Guinea coastal highland are established by the valleys of the Corubal, Konkouré 1700 Altimetry pro le 2a - 2b Luc Ferry 2017 and Kolenté rivers as well as the Tominé (Corubal DB), Bakolo (Fatala DB) 1500 Peak 1245 m and Kakrima (Konkouré DB) rivers; a limit passing through the Kondiwel 1300 Pass pass between the Fatala and Konkouré rivers basins. 1100 2-a Kondiwel, 433 m Lontonkon, 396 m 900 716 m OTHER MOUNTAINS IN THE AREA 700 80 m 500 The highland of the Siguirini/Baléa and Madinani regions, as well as the 2-b 300 Alt. (m) Manding Mounts (and their extensions to the north and northwest) are 100 Fouta Djallon highland Guinean coastal highland delineated in the same way as the three previous highlands: boundary going through the passes identified for each geomorphological unit and 0 25 50 75 100 125 150 175 200 225 250 275 300 325 350 375 400 Distance (km) use of the closest talwegs (figure 3). With boundaries that are not clearly Figure 2 > Altimetry profile and drainage divided line between Fouta Djallon highland and Coastal Guinea Highland delineated, the Banié Niandian range is approximately outlined here. (Profile 2-a 2-b map 5) The very theoretical delineations of the seven highlands identified from elevation criteria obviously do not exclude other determining factors, especially historical and cultural ones, particularly in the Fouta Djallon highland and the Manding Mounts. Yet, let us underscore a relatively good match between the boundaries of the mountain highlands and the boundaries of the geological terrains or group of terrains. 1200 Altimetry pro le 3a - 3b Luc Ferry 2017 1100 Peak Outside of these mountain highlands, the space is occupied by the 1000 Pass Léguétéra, 1011 m low amplitude hills from which a few isolated peaks, rarely exceeding 900 3-a 850 m an altitude of 500 m, rise. Lastly, a non-negligible part of the landscape 800 Didi, 807 m 761 m Famansa, 785 m concerns floodplains with gentle slopes which include those located in 700 3-b 600 the low valleys of the Niger, Senegal, Gambia and Rio-Corubal rivers. 500 400 Séla, 404 m Nimalo - Konsolon 418 m Alt. (m) Bonmborou, 364 m 300 Fouta Djallon highland Highland of Siguirini / Baléa Manding mounts 200 -75 0 75 150 225 300 375 450 525 600 675 750 825 900 975 1050 1125 1200 1275 1350 Distance (km) Figure 3 > Altimetry profile and drainage divided line between Fouta Djallon highland, Siguirini-Baléa highland and manding mounts (Profile 3-a 3-b map 5) 1 Siguirini is a sub-prefecture of Guinea (not to be confused with Siguiri). Baléa is the chief town of the municipality of Koulou in Mali. 2 Madinani is a department of Côte d’Ivoire. 17 Massif topographique du Fouta Djalon à l’altitude 440 m TOPOGRAPHY FOUTA DJALLON HIGHLAND TOPOGRAPHY Above the neighbouring plains occupied by the forest and savannah, the Fouta Djallon highland (Map 6) have sheer cliffs surrounded by rivers which flow down the slopes. Based on topographical criteria, it has a surface area of nearly 47,000 km2 and flows through Guinea (96%), Mali (3%), Sierra Leone and Senegal (<1%). It has quite clear borders, notably towards the west, and a tabular trend with a ge- neral decreasing gradient from west to east. The average altitude of the highland is around 686 m and its average gradient is 16%. Most mountains are between 500 m and 850 m tall (63%). However, moun- tains above 1,200 m, which are steeper, represent under 1% of the highland. Mountains over 1,100 m are nearly all located to the west of the highland where four groups can be distinguished: • The neighbouring mountains in the prefecture of Mali which ove- rhang The Gambia plains which are one thousand metres hight, with the following main mountains: Loura (1,538 m), Mbara (1,236 m), and Bamba (1,214 m); We also can find a peak well known as the “Lady of Mali” in reference to the shape of a face in the overhang when seen from a certain angle. • The centre-west mountainous zone, the broadest and largest highlands, next to the prefectures of Lélouma, Labé and Pita, with mountains which rarely exceed 1,250 m in altitude: Kokou (1,287 m), Limboko (1,255 m); • The Lélouma ridge in Télimélé including Djidjip (1,245 m); • The Diagissa region (1,427 m) which is also the peak of the Senegal river basin. • To the East, the plateau drained by the Bafing and the Téné rivers, at a lower altitude (750 m average altitude) and a less divided topogra- phy, are a pedestal for the powerful Haut-Fouta cliffs. Map 6 > Topographic highland of Fouta Djallon at 440 m above sea level From Luc Ferry 2017 GUINEAN DORSAL TOPOGRAPHY The Guinean Dorsal (Map 7) is formed of cristalline bedrock. Here, the Guinean Dorsal is distinguished from the Fouta Djallon highland. 1500 Altimetry pro le 4a - 4b Luc Ferry 2017 Peak 1381 m They cover four countries: Guinea (70%), Ivory coast (15%), Libe- 1300 Pass ria (9%) and Sierra Leone (6%). There are various mountains over 1100 4-a 1200 m, such as: Luma Manza (1950 m), Mont Nimba 1752 m and 900 Fari (1656  m). Despite having some of the tallest mountains in the 700 region, the average altitude and gradient of the Guinean Dorsal 500 4-b (563  m, 13%) are lower than the Fouta Djallon highland (686  m, 300 16%). The Guinean Dorsal is composed of a collection of mountains Alt. (m) Guinean Dorsal 100 often separated by foothills between 440 m and 650 m high. This range of altitudes covers over 80% of the highland with an average 0 25 50 75 100 125 150 175 200 225 250 275 300 325 350 375 400 425 450 475 500 525 550 Distance (km) gradient of around 10%. However, mountains over 1000 m altitude Figure 3 bis > Altimetry profile and drainage divided line of Guinean Dorsal (Profile 4-a 4-b map 5) represent less than 1% of the entire highland but with an average FOUTA DJALLON HIGHLAND WATER ATLAS • THE PHYSICAL ENVIRONMENT OF FOUTA DJALLON AND ITS EXTENDED AREA Massif topographique de la dorsale guinéenne à l’altitude 440 m gradient of 40%. From 1400 m altitude the gradients exceed 50% with maximums between 1650 m and 1850 m. Eleven mountainous sub-highlands can be distinguished between the Southern edge of the Guinean Dorsal and the central region of this dorsal. SUB-HIGHLANDS ON THE SOUTHERN EDGE OF THE GUINEAN DORSAL • The Luma Mansa highland (1950 m) and Farankoli (1651 m), • The Tingi mountains, the peak of which is Sankanbiriwa (1853 m), • The peak of the Kpandemai region (1381 m), • The N’Balassou (1235 m), Gnali (1348 m) and Bala (138 7m) ridge, • The Mont Nimba highland (1752 m), • The summits of the Mom (1302 m) and Doutan region (1350 m), • The summits located to the north of the town of Man (maximum around 1252 m) in the Dans mountains. SUB-HIGHLANDS IN THE CENTRAL REGION • The summits rarely above 1200 m altitude located to the east and nor- th of the town of Macenta including Sanigbé (1296 m), • The Simandou chain, which stretches nearly 100 km from north to sou- th at a width of fifteen kilometres and several peaks exceeding 1400 m altitude including Diodo (1491 m), Tibé (1574 m) and Fari (1656 m), • The summits located to the north of Beyla including Karabadougou (1230 m), • The Tétini highland (1297 m). Map 7 > Topographic highland of Guinean Dorsal at 440 m above sea level From Luc Ferry 2017 TOPOGRAPHY OF OTHER SURROUNDING HIGHLANDS THE NORTH-EAST EXTENDED HIGHLANDS OF FOUTA DJALLON THE GUINEA COASTAL HIGHLANDS The Banié Niandan chain crosses the Niger upper river basin from The Guinea coastal highland (Map 8) is located to the south-west west to east. It has topography made of greenstone (ancient meta- of the Fouta Djallon highland and are nearly fully located in Guinea volcanic rocks). We underline that the Fomi dam project is located at with a small part in Guinea Bissau. From a geological point of view, the crossing with the Niandan. The Sigurini region highland and the the highland are relatively homogeneous with around: 85% sandstone, Mandingues mountains, located next to the Fouta Djallon highland, conglomerates, siltstones and argilites with gabbro, diorite and dole- are mentioned here as a reminder but they have significant effect rite intrusions (7%). Outside of the coastal plain, the watershed for the on the hydro-sedimentary operation of the Niger river and irrigated Kogon and Nunez rivers are entirely located in the Guinea coastal farming on the alluvial plains located on the left bank. These two highland. It is crossed by the Fatala and Konkouré rivers. highlands are separated by a narrow hilly area which marks the limit between the Niger and Senegal river basins. Tinkisso falls near Dabola 19 FOUTA DJALLON RIVERS AND RIVER BASINS THE WATERSHEDS OF THE SENEGAL, GAMBIA, RIO CORUBAL, LITTLE SCARCIES AND KONKOURÉ RIVERS ARE THE MOST DEPENDENT UPON THE FOUTA DJALLON HIGHLAND. THE NIGER RIVER BASIN DEPENDS UPON BOTH THE FOUTA DJALLON AND THE GUINEAN DORSAL. IN TOTAL, 20 MA JOR RIVER BASINS WERE IDENTIFIED BETWEEN THE FOUTA DJALLON AND THE GUINEAN DORSAL, INCLUDING 15 TRANSBOUNDARY ONES. Table 2 > Main characteristics of river basins 20 MAJOR RIVER BASINS IDENTIFIED IN THE LENGTH OF SURFACE SECTOR HIGHLANDS ASSOCIATED RIVER BASIN THE LONGEST RIVER BASIN COUNTRY GEOGRAPHIC AREA AREA (KM²) TALWEG (KM) WITH THE RIVER BASINS Amongst the infinite number of river basins and sub-river basins that Algeria, Benin, Burkina Faso, Guinean Dorsal, Fouta Djallon, it would be possible to map, only the river basins over 4000 km2 are Cameroon, Côte d'Ivoire, Siguirini-Baléa highland, Banié- Niger > 2,000,000 4,260 described here, where the rivers have their sources in the West Africa Guinea, Mali, (Mauritania), Niandan chain, Mandinani Niger, Nigeria, Chad highland and Manding Mounts water tower region (Heart of the Fouta Djallon highland and Guinean Dorsal). 25 river basins have been delineated which includes 18 trans- Guinea, Mali, Fouta Djallon, Coastal Guinea Highland Senegal > 400,000 2,170 boundary basins. Amongst the 25 river basins, only 5 of them do not Mauritania, Senegal and Siguirini-Baléa highland have their springs in the 7 identified highlands: the Cacheu (or Rio Sassandra 68,550 915 Côte d'Ivoire, Guinea Guinean Dorsal and Madinani highland Cacheu), the Casamance, the Géba, the Jong, and the Sehnkwehn. We Gambia 67,350 1,160 The Gambia, Guinea, Senegal Fouta Djallon can underline that the Géba, at its outlet, shares the same outlet than Rio-Corubal and could be linked with Rio-Corubal river basin. Finally, Cavally (Cavalla) 29,600 775 Côte d'Ivoire, Guinea, Liberia Guinean Dorsal it is 20 river basins that depend directly of highlands of the area of Fouta Djallon and Guinea Corubal 24,700 815 Guinea, Guinea Bissau which 15 are transboundary (map 8). Related area of these river basins Coastal Highlands and by mountainous highlands are given in the table 2. The name gi- St Paul 20,150 510 Guinea, Liberia Guinean Dorsal ven to each river basin, determined from maps at a scale of 1: 200 000 and 1: 250 000, is the name of the river at its mouth or its confluence Moa 19,700 520 Guinea, Liberia, Sierra Leone Guinean Dorsal with another river. Along their route, the rivers can have different Little Scarcies 18,400 445 Guinea, Sierra Leone Fouta Djallon and Guinean Dorsal names. Therefore, the longest talweg of the Senegal river basin has (Kaba/Mongo) the name Senegal up to its confluence with the Bakoye, Bakoye up to Fouta Djallon and Guinea its confluence with the Baoulé and finally Baoulé. We underline that Konkouré 16,750 385 Guinea Coastal Highlands the same river can have different names depending on the country in St_John 16,150 455 Guinea, Liberia Guinean Dorsal which they flow: Great Scarcies in Sierra Leone and Kolenté in Guinea, Cavalla in Liberia and Cavally in Ivory Coast. We also note that the Sewa 13,750 440 Sierra Leone Guinean Dorsal names of the rivers are often the same in 2 different river basins: Bafing Cestos 12,550 470 Côte d'Ivoire, Liberia Guinean Dorsal in the Senegal and Sassandra river basins, Baoulé in the Senegal and Guinea, Guinea Niger river basins. Géba 12,300 415 Outside of highlands Bissau, Senegal Finally, the definition and surface area of the Niger and Senegal river Rokel 11,300 455 Sierra Leone Guinean Dorsal basins as well as the Bakoye river basin upstream from the Falémé (Se- Loffa 10,550 420 Guinea, Liberia Guinean Dorsal negal DB) are very inaccurate due to the presence of large dune areas located to the north of these three rivers; major inaccuracies which do Kogon 7,860 450 Guinea, Guinea Bissau Guinea coastal highland not allow us to determine other physical characteristics of these three Mana Moro 7,690 395 Guinea, Liberia, Sierra Leone Guinean Dorsal river basins. Great Scarcies Guinea Coastal Highlands 7,650 305 Guinea, Sierra Leone (Kolenté) and Fouta Djallon Guinea Coastal Highlands Fatala 6,180 240 Guinea and Fouta Djallon Nunez (Rio Nunez/ 4,830 190 Guinea Guinea coastal highland Tinguilinta) FOUTA DJALLON HIGHLAND WATER ATLAS • THE PHYSICAL ENVIRONMENT OF FOUTA DJALLON AND ITS EXTENDED AREA Map 8 > River Bassins basins linked versants with Fouta en lien avec Djallon highland, le massif duGuinean Fouta Dorsal and Coastal Djalon et la Guinea Highland Dorsale Guinéenne -15.0 -10.0 -5.0 0.0 5.0 10.0 15.0 20.0 Flooding area of inner Niger Delta NOUAKCHOTT 200 mm Tombouctou Senegal Niger 15.0 DAKAR Kayes 500 mm Gambie BANJUL NIAMEY Géba BAMAKO OUAGADOUGOU BISSAU NDJAMENA Corubal 100 0 mm Kogon Koroussa Nunez 10.0 Fatala CONAKRY ABUJA Konkouré FREETOWN Great Scarcies (Kolenté) 2000 mm Little Scarcies (Kaba - Mongo) YAMOUSSOUKRO Rokel MONROVIA m PORTO-NOVO Jong 1500 m LOME 3000 mm Sewal ACCRA 5.0 A Moa G U I N T E A 400 200 Mana Morro N 4000 L mm 300 0m G 0m YAOUNDE A U 0m m Lo a m N Topographic highland of Fouta Djallon L m T Saint Paul I F C Saint John O Cestos Topographic highland of Guinean Dorsal C Sehnkwehn Cavally E Sassandra A N Projection latitude - longitude WGS 84 - Géohyd - topographic highlands from L. Ferry, 2017 - Mean annual isohyetes from 1951 - 1989 from l’Hôte & Mahé IRD, 1995 - Created by Géohyd Anteagroup - Luc Ferry & Axel Aurouet 2017 21 RIVER BASINS THE SOUTH-WEST RIVERS AND RIVER BASINS Apart from the Géba, Corubal, Kogon and Nunez (Rio Nunez/Tin- FATALA AND KONKOURÉ RIVERS Further downstream, its main Guinean tributaries are the Santa and guilinta) rivers, the South-West rivers in the study area have more the Kilissi. The slope of the upper portion remains very high (3m/ The Fatala is a powerful river flowing from the foothills of the Fouta direct paths to the sea. This includes the Fatala, Konkouré, Great km) then falls gradually. Finally, the high basins of Kaba and Mongo Djallon where it has its source close to Télimélé (1000 m). The slope Scarcies (Kolenté), Little Scarcies (Kaba, Mongo), Rokel, Jong, Sewa, in Guinea drain the extreme south-east of the foothills of the Fouta of the Fatala is significant (over 3  m/km), its riverbed is broken up Moa, Mana Moro, Loffa, St Paul, St John, Cestos, Sehnkwehn, Cavally Djallon. These two large river basins constitute the Little Scarcies that with rapids and waterfalls (Diou waterfall). At around 100 km from (Cavalla) and Sassandra rivers (map 9). The South-West river basins in ends its race in Sierra Leone. its source, its receives the Télébou on its right bank. The Konkou- the study area (from the Corubal up to the Sassandra) receive rain- ré is the most powerful river solely in Guinea, which starts close to fall between 1,500 mm/year and over 4,000 mm/year (1951-1989 Mamou in the Fouta Djallon highland at an altitude over 1000 m. In period, L’Hôte Y., Mahé G., 1995). Six main river basins make up the its upstream part, it is guided by rifs in the Fouta Djallon sandstone hydrographic network of the oceanic front with sources linked to highland. The Konkouré, its tributaries and sub-tributaries (the Kakri- the centre and foothills of the Fouta Djallon highland. These are the ma, the Kokoulo) have crossed deep valleys with impressive water- basins of Kogon, Tinguilinta, Fatala, Konkouré (originating in Fouta Kinkon falls Kokoulo falls. The gradients are more significant (3  m/km) on the upstream Djallon), Kolenté which becomes Great Scarcies in Sierra Leone, and part. On the downstream part, the Konkouré is reinforced on the left Kaba, which becomes Little Scarcies in Sierra Leone (map 9). These 2 bank by the Badi, the tributaries of which (Samou and Wantaba) flow latter rivers are therefore international. down the main foothills from the south of Fouta Djallon to the south KOGON AND TINGUILINTA RIVERS of Kindia. Next the Konkouré continues in an enclosed valley which narrows before arriving in a mangrove forest. The longitudinal pro- The Kogon is a coastal river which originates in Coastal Guinea file of the Konkouré (and 19 of its tributaries with a catchment area of Highland in the South-West of Fouta Djallon Highland. It has a rela- more than 200 km2) (figure 4) shows the often-important falls (from tively sustained slope (2m/km) for the first hundred kilometres (up to ten to sometimes a hundred meters) in the downstream part and a its first right bank tributary, the Linkourou). Then the Kogon spreads morphology favorable to the installation of hydroelectric structures. into various meanders into a huge alluvial plain before emptying into the ocean through a large estuary overrun by mangrove trees. The GREAT AND LITTLE SCARCIES Tinguilinta is a coastal river draining the hills of the Boké region. The The Kolenté is a boundary river with Sierra Leone, before entering Tinguilinta has two small right-bank tributaries, the Bouroundou and the country where it becomes the Great Scarcies river. The upper the Batafong, and on the left bank the Bourouma. These basin heads basin of this river drains the Southern foothills of Fouta Djallon to the have an average slope (0.5m/km), contrary to the downstream por- North-East of Kindia, where it receives a left-bank tributary: the Kara. tions where the river and its tributaries flow into an alluvial plain. Konkoure River pro le and main a uent pro les - from its source to its marine outlet in Guinea 1300 Con uence (outlet) Luc Ferry, 2017 Kassa Fétoré Kan Han Piké Samou - Badi Soukoa Taouli Baki 1200 Kokoulo Kottoto Kaga Tonionkou Existing dam 1100 Mitti Consirah Conni 1000 Mayonkouré Dam site Koufa 900 Other dam site 800 Sala Sangan (from hydraulic master plan of Guinea) 700 Kakrima Konkouré/Taouli 600 Konkouré Banéya Gara ri Kaléta 500 Konkouré Sup. Grandes Kalé Chutes Souapiti Konkouré/Conni 400 300 Badi/Tonionkou 200 Kakrima/Kassa Konkouré/Badi Kokoulo/Mitti Kakrima/Fétoré Kokoulo/Kottoto 100 Badi/Soukoa 0 Konkouré Sup./Koufa Konkouré/Kakrima Badi/Baki Alt. (m) Konkouré Sup./Kan Han Konkouré Sup./Piké Sea Kakrima/Kokoulo Konkouré Sup./Sangan Konkouré/Mayonkouré Badi/Konsirah Konkouré/Kaga 380 350 320 290 260 230 200 170 140 110 80 50 distance to the sea (km) Figure 4 > Longitudinal profile of Koukoure and its main tributaries FOUTA DJALLON HIGHLAND WATER ATLAS • THE PHYSICAL ENVIRONMENT OF FOUTA DJALLON AND ITS EXTENDED AREA Map 9 >d’eau Cours bassins et basins Rivers and versants of south-west dearea la façade océanique coastal BANJUL -15.0 -10.0 -5.0 Gambie Sénégal Casamance BAMAKO eu Cach Géba Niger BISSAU Corubal Komba Fé né Kogon Kakrima Nunez Fatala Konkouré Kaba Great 10.0 Scarcies Mongo CONAKRY Little Scarcies A Rokel Boa Topographic highland Sewal of Fouta Djallon T Sassandra FREETOWN Méli Jong L Moa Ba ng A N Saint Paul T Nzo I Lo a YAMOUSSOUKRO Saint John C Goré Mana Morro O MONROVIA C Cestos Cavally Topographic highland E of guinean dorsal A Sassandra N Sehnkwehn 5.0 Projection latitude - longitude WGS 84 - Géohyd - topographic highlands and watersehed from L. Ferry, 2017 - Created by Géohyd Anteagroup - Luc Ferry & Axel Aurouet 2017 23 RIVER BASINS INTERNATIONAL RIVERS FLOWING FROM THE HEART OF FOUTA DJALLON HIGHLAND SENEGAL RIVER BASIN Bafing and Falémé at the source of the Senegal river Koulountou. Upstream from the Kounsi, Gambia receives the Lili and then the Silame on the left bank. The upper basin of The Gambia Main description The Bafing is the main constituent of the Senegal and has its source drains the North of the Fouta Djallon plateau, without the waterfalls near to Mamou (nearly 1,000 m altitude). It drains the entire Eastern The Senegal river basin crosses four countries: Guinea, Mali, Mauri- found in other rivers, but the slope is still steep (over 4 m/km for the part of the Fouta Djallon through the upper basin itself. Its main right tania and Senegal (map 10). The Senegal and Niger river basin are first 100 km). The slopes are no more than 1 m/km at Kounsi. Several bank tributaries are the Sokotoro, the Téné, the Dombélé, the Kioma identical in term of climatic regions (Guinean, South Sudanese, North other tributaries from the northern foothills of Fouta Djallon, at the and the Samenta. Its main left bank tributaries (Koukoutamba) are less Sudanese, Sahelian, Semidesert and Desert). The longest talweg of non-permanent flow on the Guinea portion, flow towards the Gam- significant. The upper basins of the Bafing (and its right bank tribu- the river basin is composed of (from downstream to upstream) the bia river in Senegal, including the Kanta, Tiokoï and Diahra. taries) have spectacular rapids and waterfalls. The slope for the first Senegal river up to its confluence with the Bakoye river, the Bakoye 100 kilometres is intense and exceeds 5 m/km. After over 300 km in CORUBAL RIVER BASIN up to its confluence with the Baoulé, the Baoulé up to its confluence Guinea, the Bafing enters Mali for around fifty kilometres. It is still tu- with the Banangazalé and the Banangazalé. Further upstream, this river The Corubal river basin (map 10) has a surface area of 24,700 km2. multuous in this sector and has narrow straight joints(figure 5). has several names: Koyo (or Koya?), Dyoumara, Koronglali, valley of Upstream, the Corubal river is formed by the confluence between the serpent (vallée du serpent), Gélédo, Fanta, Kolossa. With rainfall The Falémé also has its source in the Northern foothills of the Fouta the Komba and the Tominé, rivers with sources in the Fouta Djallon between 300 mm/year to the North and 800 mm/year to the Sou- Djallon in Guinea and is a major tributary of the Senegal river which highland at 1150 m and 1050 m altitude respectively. Along its cen- th (1951-1989 period, L’Hôte Y., Mahé G., 1995), the flows of most it joins at the meeting point of the Mauritania, Senegal and Mali bor- tral path, on its left bank it receives the Féfiné, the source of which rivers in the Bangazalé river basin are probably sporadic and rarely ders, in the town of Ballou. In its upper course, its main left-bank is located at least 400 m high in the Guinea coastal highland. In Gui- contribute to supplying the Senegal river. The Senegal river is mainly tributary is the Koila, (the source of which is in the Northern foo- nea-Bissau, the river takes the name of Corubal, whereas in Guinea it supplied by the Fouta Djallon highland (Bafing and Falémé DB) and to thills of Fouta Djallon) and on the right bank, a course formed by the is called Koliba, at least for its western portion. Before its confluence a lesser extent by the Siguirini/Baléa Mountains (Bafing and Bakoye DB) confluence between the Koulounko and the Kounda Ko (sources in with the Tominé towards Gaoual, it is known as Komba. Then, the and the Mandingues Mountains (Bakoye and Baoulé DB). The longitu- Guinea in the North-Eastern foothills of Fouta Djallon). Komba (Kolimba) joins with the Tominé. The Tomine receives the dinal profile along the Senegal river and its main tributaries (Figure 5) Kokoni on the right bank which successively grows with the Bantala GAMBIA RIVER BASIN show clear differences between the rivers which have their sources in on the right bank and the Ouésséguélé on the left bank. The gra- the Fouta Djallon highland (Bafing, Falémé), the Siguirini/Baléa moun- With a surface area of 67,350 km2, the Gambia river basin is the 3rd dients of these upper basins are strong, there are many waterfalls tains (Bakoye upstream from its confluence with the Baoulé) and the largest basin in the region (map 10). It is a transboundary river basin and rapids, and the drained valleys are still embedded between Mandingues Mountains (Baoulé, Banagazalé). The longitudinal profile which covers The Gambia, Guinea and Senegal. Its average altitude the high cliffs of the Fouta Djallon sandstone plateaus. The different along the Bafing, “stepped”, is like the longitudinal profiles along the and gradient are 131 m and 5.2% respectively, which are quite low. names of the river used in Guinea (Koliba, Komba, Tominé) before Konkouré and some of its tributaries which also have their sources in The Gambia river, initially flowing S E/NW and then downstream it becomes the Corubal in Guinea-Bissau illustrates the example of a the Fouta Djallon highland. E/W, has its source in the Fouta Djallon highland at the approximate sector which is rarely described in literature. altitude of 1,150  m. Its main tributaries are Nianja Bolon, Sandou- gou, Kolountou and Niériko. The Gambia river basin is represented in Guinea by the upper basin of The Gambia and its tributary, the Senegal river pro le and main a uents pro les - from its source to marine outlet in Senegal Ba ng Luc Ferry, 2017 900 Koukoutamba 800 Banangazalé Bakoye AM Baoulé Balasa Falémé 700 Baoulé Niagara Bakoye 600 Diaoya Manantali Sénégal 500 Boureya Kayes 400 Badoumbé Gourbassy Félou Saint Louis 300 Con uence (outlet) 200 Gouina Bakel Matam Richard Toll Diama City Podor 100 0 Existing Dam Sénégal / Baoulé AM Bakoye Alt. (m) Dam site Sénégal / Ba ng Sénégal / Falémé Sea 2100 1900 1700 1500 1300 1100 900 700 500 300 100 Distance to the sea (km) Figure 5 > Longitudinal profile of Senegal and its main tributaries FOUTA DJALLON HIGHLAND WATER ATLAS • THE PHYSICAL ENVIRONMENT OF FOUTA DJALLON AND ITS EXTENDED AREA Cours et bassins Map 10 > Rivers versants and basins du of Sénégal, Sénégal, Gambia, de Geba and la Gambie, du Géba et du Corubal Corubal NOUAKCHOTT Senegal Senegal before con uence with Falémé 15.0 DAKAR Nianja Bolon Banangazalé Inner Sandougou Bakoye Niger Delta Gambia Falémé Baoulé BANJUL Niériko Gambie Ko Niger ul Ba ng BAMAKO ou nt ou Geba BISSAU Komba Corubal Fe ne Topographic highland of Téné Fouta Djallon Projection latitude - longitude WGS 84 - Géohyd - topographic highlands and watershed from L. Ferry, 2017 - Created by Géohyd Anteagroup - Luc Ferry & Axel Aurouet 2017 25 RIVER BASINS NIGER RIVER BASIN AND ITS MAIN TRIBUTARIES This group is linked to both the Fouta Djallon highland, with the metres. Then, till Bamako, Niger river will keep a stable morphology, dam project is planned, before emptying into the Niger around source of the Tinkisso, and the Guinean Dorsal. Most of the Niger with high banks, flood plains, multiples islands with a smooth slope Koumana. The Milo itself loses 200 m in 30 km (6.7 m/km) before River’s tributaries also have their source in the northern foothills of of 0.12m/km. In Guinea, it collects water from tributaries Niandan racing into a valley bordered to the East by doleritic mountains. It the Guinean Dorsal (Niger, Sankarani, Milo, Niandan, Fié, Kouya, Ma- and Milo and right riverside. The latest and strong Guinean tributary, reaches the first flood plains around Kérouané before receiving its fou...). This large “basin” surrounded by the Fouta Djallon highland Sankrani cross Niger river in Kourouba, Mali, after feeding the mas- main tributary, the Baoulé, on the left bank. After a series of rapids, to the west and the Guinean Dorsal to the south is the upstream of sive Selingue dam. it has a similar appearance to the Niandan lower valley to join the the hydrological entity of the Upper Niger, an entity which flows to Niger around Sansando. It flows in the Niger inner delta area, with a surface area of around Mali upstream from the inner delta (between Ségou and Markala THE TINKISSO, THE PORTION OF THE NIGER IN FOUTA DJALLON 50,000 km2, with 20 to 30,000 km2 flood plains, the inner delta is a in Mali). The Niger river basin has a specific role due to the climate complex system of channels and lakes. It is mainly supplied by the This is the sole Niger tributary which starts in the Fouta Djallon regions that it occupies (Guinea, South Sudanese, North Sudanese, upper Niger river basins and to a lesser extent by the Bani. More highland. It starts at an altitude of around 850 m, races down a steep Sahalian, Semidesert and Desert), the number of countries covered than 40% of inputs are lost there by evaporation. Downstream slope (5 m/km) and various waterfalls. At Dabola, it is only at 400 m and the number of countries crossed by its river (Guinea, Mali, Niger, from the Koryoumé, the river inputs flow back at the level of its left altitude. From then, the slope slows quickly (0.5 m/km) until its left Nigeria) or bordered by its river (Benin, Nigeria); a river which is also bank tributaries including the Gorouol, the Dargol and the Sirba. bank confluence with the Bouka. Its gradient slows a little more noted as it crosses the Niger inner delta, the largest wetland in West Downstream, the Niger river receives inputs from the Bénoué, a ma- (0.05 m/km) until its confluence with the Niger towards Siguiri. It has Africa (map 11 and figure 6). jor tributary of the river’s lower course. many sinuosities leading to huge flood plains. UPSTREAM PART OF NIGER RIVER THE MILO AND THE NIANDAN THE SANKARANI, AT THE EASTERN EDGES OF GUINEA In its upstream part from the inner delta area, the Niger basin has The Niandan and the Milo have their sources in the Northern foo- The Sankarani starts at the meeting point between the Gbanhala and two main basins, the Bani to the east and the upper Niger to the thills of the Guinean Dorsal at an altitude of 700 m for the Niandan the Kouroukélé, both from the Northern edge of the Guinean Dor- west. The latter has seven main branches: the Tinkisso, the Niger it- and 1,000 m for the Milo. The Niandan has a steep slope of 4m/km sal. They arise at around 700 m altitude and meet after a series of self or Djoliba, the Mafou, the Niandian, the Milo, the Fié and the up to the Kissidougou station. The slope lowers to 0.5 m/km up to small rapids in sloping desert valleys. The slope slows and the Sanka- Sankarani. The slope of Niger river is important on the first 40 kilo- the Balé confluence at Sansanbaya. The Niandan then moves through rani receives the Kouraï on the right bank and above all the Dion on meters (7.5 m/km) and reduce around Faranah (figure 6). Its slope is a series of powerful rapids before receiving the Kouya on the left the left bank, its major tributary in this region. Upstream from the stable even near tributaries flowing the Fouta Djallon highland (Balé, bank and settling into a large flood plain. It then passes through the Sélingué dam in Mali, it receives another tributary, the Ouassoulou Koba, Niantan). After the junction with the tributary Mafou, Niger narrowing of the Niandan-Banié chain, a narrowing where the Fomi Balé, with its source on the border between Guinea and Mali. river shows important rapids and its altitude decrease from a dozen Niger river pro le - from its Guinean source to its outlet in Nigeria 900 Luc Ferry, 2017 800 Guinea Mali Niger Benin Nigeria 700 Sotuba Kénié Markala Taoussa Kandaji Niger Malanville Kainji Jebba 600 Koryoumé Faranah Kouroussa Siguiri Bamako Ségou Mopti (Tombouctou) Bourem Niamey Yelma Lokoja Onitsha 500 400 300 200 Inner Niger delta (IND) Cities 100 Existing dam Alt. (m) 0 Dam site Distance to the sea (km) 4300 4100 3900 3700 3500 3300 3100 2900 2700 2500 2300 2100 1900 1700 1500 1300 1100 900 700 500 300 100 Figure 6 > Longitudinal profile of Niger and its main tributaries FOUTA DJALLON HIGHLAND WATER ATLAS • THE PHYSICAL ENVIRONMENT OF FOUTA DJALLON AND ITS EXTENDED AREA Cours d’eau Map 11 > et sous Rivers and bassins sub-basins versants of upstream de l’amont du euve Niger Niger river Inner Niger delta Sénégal -10.0 -5.0 Baoulé MARKALA Manding mounts SEGOU NIGER Ba ng Bakoye KITA Bani KOULIKORO Upstream Niansira Highland of Siguirini-Baléa region BAMAKO Falémé Baoulé Bani ng Bani basin Kouoro Gambie Bagoé Bani Basin Topographic highland Fié DINGUIRAYE SIKASSO of Fouta Djallon Tinkisso Téné DABOLA Sankarani Ba ng KANKAN MAMOU Upstream Niger Kaba Milo FARANAH Mafou Dion 10.0 Mongo BOUNDIALI Rockel Niandan Little scarcies KISSIDOUGOU Highland of Madinani region Sewal Sassandra Moa Saint Paul Guinean Dorsal Lo a Projection latitude - longitude WGS 84 - Géohyd - topographic highlands and watershed from L. Ferry, 2017 - Created by Géohyd Anteagroup - Luc Ferry & Axel Aurouet 2017 27 GEOLOGY OF FOUTA DJALLON AND ITS EXTENDED AREA SHAPED OVER THE COURSE OF SUCCESSIVE TECTONIC CYCLES WHICH BEGAN MORE THAN 2 BILLION YEARS AGO, THE FOUTA DJALLON HIGHLAND ARE MOSTLY COMPOSED OF ACID ROCK (SANDSTONE, SHALE) WITH THE INTRUSION OF OLD REWORKED IGNEOUS ROCKS THAT ARE MORE BASIC (DOLERITE). THIS DOLERITE CORE CREATED THE POWERFUL TOUGUE-MALI RELIEF. GEOLOGICAL HISTORY Tinkisso and Milo are nearly monolithologic basins in sandstone or gra- GEOLOGICAL FEATURES OF THE SENEGAL MIDDLE BASIN nite (table 3). The basins where the basic rocks are most common are the The heart of the Fouta Djallon highland are located on the SW edge of On the northern part of the Fouta Djallon highland, entering into the basins of the Gambia and Falémé rivers. the West African craton (map 12). This vast geological complex, stabi- Western part of Mali, there is a mainly sandstone infra-Cambrian sedi- lised at the end of the Eburnean orogeny, around 1800-1600 million SUMMARY OF THE GEOLOGICAL GROUPS mentary coverage in the extended areas of the Guinea Mali-Tougué for- years ago, is limited by mobile zones formed or rejuvenated during mations and which is the start of the Taoudéni sedimentary basin. These later orogenic phases, pan-African (660 and 550 million years ago), Hy- AROUND FOUTA DJALLON IN THE formations are located up to Bamako (Sotuba sandstone formations) cernian (250 million years ago) or Alpine (60 million years ago) cycles. EXTENDED AREA and constitute the geology of the middle part of the Senegal basin. Standard thinking considers the West African craton as a continuous unit TERTIARY FORMATIONS IN THE INNER DELTA OF THE NIGER, GEOLOGY OF THE GUINEAN DORSAL AND THE UPSTREAM stretching from Mauritania to Algeria, to the North, and to Ivory coast SENEGAL AND GAMBIA RIVERS. BASIN OF NIGER RIVER and Ghana to the South (Bessoles, 1977). This cratonic platform is made of a bedrock ridge to the North (Réguibat-Algeria-Mauritania ridge) The Guinean Dorsal, the source of the Niger river and its tributa- The most recent sedimentary formations are only located in the upper and another one to the South (Léo ridge), and between the two, a sedi- ries (Milo, Niandan, Mafou, etc.), are marked by granites of the basin of Senegal river by a Continental Terminal outcrop, located to the mentary covering (Taoudéni basin) with two bedrock windows (Kayes granite Archean bedrock with doleritic intrusions identified next east of Nioro at the limit between the Senegal river basin and the Niger window and Kéniéba window). The main West African rivers flow in this to Beyla and some gneiss series with quartz in the Nzérékoré sec- river basin. The Continental Terminal is largely represented in the Se- vast geological unit: the Niger, the Senegal and the Gambia River. tor. The coverage of the granite bedrock extends into the Kankan, negal lower river basin and the middle portion of the Niger river basin Kérouané basin. These granite coverages are found in the Foréca- (from the Markala surrounding area - Niger inner delta up to Gao). The GEOLOGY AT THE HEART OF THE FOUTA riah-Coyah maritime sector, in the extension crossing Sierra Leone. Continental Terminal is composed of clayey sands in highly varied co- lours interbedded with clay or sandstone layers. Taoudéni basin main DJALLON HIGHLAND In the downstream part of the Niger basin (Siguiri basin), there is a geological formation, the thickness of the Continental Terminal is va- coverage of Birimian schist, sometimes injected with dolerites in the This highland is divided into three equal parts, the soft sandstone to the Northern part of Siguiri, which flows into Mali in its south-east part. riable depending on the structures of the sedimentary storage basin. West, granites to the South East and quartzitic sandstone to the Nor- From one hundred meters average depth in the Niger inner delta and th-East. The Lélouma-Pita-Labé-Dalaba-Télimélé group corresponds to up to 2000 m depth in the Gao rift. the sandstone Fouta Djallon made up of soft sandstone and schist often injected with dolerites. The Mamou group corresponds to the crystal- Table 3 > lithological characteristics of few sub-basins line Fouta Djallon, mainly made of granite bedrock extended from the LITHOLOGICAL CLASSES Kankan basin with a thin alteration layer (table 3). Finally, the last doleritic RIVER BASIN OUTLET Quartz Fouta Djallon group (Mali-Tougué and Koubia), also mainly sandstone Granites Sandstone Schist Dolerites Greenstone sandstone and schist, but also marked by doleritic veins and dikes. In the last group, there is a doleritic core which makes up the heart of the mountain range. Bafing Dakka Saidou 5% 6% 1% 9% 39% 0% To the north of the Fouta Djallon highland, in Mali, there are soft Birimian Falamé Satadougou 8% 0% 16% 34% 42% 0% schists to the very south of the Kéniéba window. The coverage of the Falémé Kidira 15% 15% 36% 16% 2% 3% southern fringe of the Fouta Djallon highland (Fria-Télimélé-Kindia) and south-west (Boke-Boffa) is made up of sandstones and schists with dole- Gambia Kédougou 0% 18% 7% 45% 30% 0% ritic intrusions. The Gaoual Basin, towards Guinea Bissau, is characterised Konkouré Konkouré 0% 98% 0% 0% 2% 0% by sandstone with doleritic injections. The acid rock occupies 87% of the Milo Kankan 91% 0% 6% 0% 3% 0% total surface area of Fouta Djallon. The most common lithographic class is sandstone. Conversely, greenstone (metamorphic volcanic-sedimentary Niger Siguiri 69% 0% 26% 0% 2% 3% rocks) is the least common. They are found in the watershed of the Niger Senegal Bakel 7% 31% 7% 42% 12% 1% (table 3)., Falémé rivers and North of the Kayes in the Senegal river. The Tinkisso Tinkisso 96% 0% 0% 0% 4% 0% basic rocks are mainly represented by dolerites. The basins of Konkouré, Tominé Gaoual 0% 86% 0% 0% 14% 0% FOUTA DJALLON HIGHLAND WATER ATLAS • THE PHYSICAL ENVIRONMENT OF FOUTA DJALLON AND ITS EXTENDED AREA Map 12 > Geological Geological context context ofofFouta Fouta Djallon and its Djallon extension zones highland and its extension zones DAKAR Taoudéni Sénégalo basin Mauritanian basin BANJUL Kéniéba window BAMAKO West African Shield Extended extension area (Leo Dorsal) from RPID FDH BISSAU Bové Basin Extension zone of Fouta Djallon highland from FAO Topographic highland of Fouta Djallon CONAKRY Topographic highland of Guinean Dorsal FREETOWN D’après / From : Thiéblemont D. (edit.) et al. - Geological Map of Africa at 1:10 M scale, CGMW-BRGM 2016. ISBN: 9782917310328. doi: 10.14682/2016GEOAFR. ARCHEAN PROTEROZOÏC PALEOZOÏC MESOZOÏC CENOZOÏC 3,6 Ga 2,5 Ga 541 Ma 299 Ma 66 Ma 0 Ma Paleo-archaen (3,6 - 3,2 Ga) Precambrian Paleoproterozoïc (2,3 - 2,05 Ga) Precambrian Neoprotérozoïc Sedimentary deposit Tertiary (66 -2,6 Ma) - Sedimentary Volcano sedimentary & métamorphic Sedimentary and Volcano-sedimentary (1 000 - 541 Ma) Volcano-Sedimentary from paleozoïc Paleo-archaen to Méso-archéen (3,6 - 2,8 Ga) Precambrian Paleoproterozoïc Precambrian Neoproterozoïc Quaternary and plio-quaternary Plutonic & métamorphic (2,3 - 2,05 Ga) Plutonic and metamorphic (1 000 -635 Ma) Volcano-Sédimentary (Cambrian > Dévonian / sedimentary deposit (66 - 0.012 Ma) Carboniferous) Dolerites Meso-archaen (3,2 - 2,8 Ga) Precambrian Paleoprotérozoïc Precambrian Neoprotérozoïc Métamorphic (2,3 - 2,05 Ga) metamorphic (635 - 541 Ma) Sedimentary (Trias) Meso-archaen (3,2 - 2,8 Ga) Precambrian Mesoprotérozoïc Observed Inferred Plutonic (1,6 - 1,0 Ga) Sedimentary Normal fault Meso to Neoarchaen (3,2 - 2,5 Ga) Precambrian lower Proterozoïc (1 000 - 720 Ma) Thrust fault Volcano-Sédimentary (Tonian) Sedimentary Fault Néoarchaen (2,8 - 2,05 Ga) Sedimentary and Volcano-Sedimentary Projection latitude - longitude WGS 84 - BRGM, PRAI MFD, Géohyd - topographic highlands from L. Ferry, 2017 - Created by Géohyd Anteagroup - Axel Aurouet 2017 29 LAND COVER IN THE FOUTA DJALLON HIGHLAND AND ITS EXTENDED ZONES FORESTS AND SHRUBBY SAVANNA COVER MOST OF THE FOUTA DJALLON HIGHLAND, EVEN IF THE FOREST OFTEN FOLLOWS MOSAIC PATTERNS. CUIRASSE OR LATERITIC PLATEAUS ARE ALSO A MARKER OF THE FOUTA DJALLON LANDSCAPE WHICH ORGANIZE THE TOPOSEQUENCES GUINEA’S MAJOR FOREST ECOSYSTEMS LAND COVER OF THE FOUTA DJALLON TOPOGRAPHICAL HIGHLAND BASED ON THE Seven major forest ecosystems are described in Guinea. This includes GLOBCOVER 2008 PROJECT • The Mangrove ecosystem (Amphibious forest ecosystem) in Ma- In the Fouta Djallon topographical highland, land cover associated Figure 7 > Land cover distribution in topographic ritime Guinea, with shrubby savannah and deciduous trees is the dominant land highland ofcover Land Fouta Djallon (Glob distribution cover 2008) in topographic highland cover (39% - Figure 7), and distributed more on the edges of the of Fouta Djallon (Glob cover 2008) • The Guinea coastal woodland in Maritime Guinea along the river, topographical highlands than the centre, which is rather dominated along the banks of Marais and all rich soils by vegetation associated with open forest and wood. This class re- • Guinea and Sudan-Guinea savannahs resulting from the degrada- presents nearly 30% of land cover in the Fouta Djallon topographical tion of woodlands. They are present across the Guinea territory highland. The other covers are marginal and mainly composed of 39% patches of vegetation distributed between trees, shrubs, grasslands • The Guinea dry forest which is the dominant category of the Fouta and crops. These patches of vegetation represent 30% of the sur- Djallon highland’ plateaus and the upper Guinea plains face area of the natural highland. Based on Globcover information • The Guinea dense forest characterised by a closed formation in 2008, the bare land and low-land crops represent less than 1% where the vegetation is exuberant, the trees very tall with constant of land cover in the topographical highland. From a spatial point of 1% 1% moisture view, the natural patches of vegetation associated with the cultivation - 30% - zones are mostly found on the Southern foothills in (Dalaba - Télimé- • The Guinea dense rainforests which are only remnants of forests, lé sector), the Eastern edges (Dabola - Dinguiraye), the specific Mali 7% especially in the Forest Guinea sector (Macenta, Nzérékoré) sector and the Western sectors of Pita – Labé (map 13). • The Guinea dry dense forest which occupies the north part of Gui- 7% nea except Fouta Djallon highland. 7% 8% In literature, the environmental findings of land use in the Fouta Djal- lon highland sector notes a forest cloak which only covers 13% of the Closed to open (>15%) (broadleaved or Central Guinea administrative region, i.e. 800,000 ha of dry dense needleleaved evergreen or deciduous) shrubland (<5m) forest and 50,000 ha of forest patches, remains of the former dense Open (15-40%) broadleaved deciduous forest/woodland (>5m) forest. It seems that there are no longer forest uplands outside of Closed to open (>15%) broadleaved evergreen or semi-deciduous forest (>5m) these small classified forests. Mosaic forest or shrubland (50-70%) / grassland (20-50%) Mosaic vegetation (grassland/shrubland/forest) (50-70%) / cropland (20-50%) Mosaic cropland (50-70%) / vegetation (grassland/shrubland/forest) (20-50%) Mosaic grassland (50-70%) / forest or shrubland (20-50%) ) Bares areas Bowal and Dakoro’s village nearby Bafing or «black river» FOUTA DJALLON HIGHLAND WATER ATLAS • THE PHYSICAL ENVIRONMENT OF FOUTA DJALLON AND ITS EXTENDED AREA Land cover Map 13 of Fouta > Land cover Djallon of Fouta highland Djallon highland and itsand its extension extension areas zones (Glob cover (Globcover 2008) 2008) -20.0 -15.0 -10.0 -5.0 15.0 DAKAR BANJUL BAMAKO BISSAU Highland of coastal Guinea 10.0 CONAKRY Manding mounts topographic highland of Fouta Djallon FREETOWN Highland of Siguirini Baléa region Topographic highland of Guinean Dorsal RPID Wider extension area of Fouta Djallon FAO extension area of Fouta Djallon Banié - Niandan Projection latitude - longitude WGS 84 - FAO, CEDEAO, PRAI MFD, Géohyd - topographic highland from L. Ferry, 2017 - created by Géohyd Anteagroup - Axel Aurouet 2017 chain 11 Post- ooding or irrigated croplands (or aquatic) 120 Mosaic grassland (50-70%) / forest or shrubland (20-50%) 14 Rainfed croplands 130 Closed to open (>15%) (broadleaved or needleleaved evergreen or deciduous) shrubland (<5m) 20 Mosaic cropland (50-70%) / vegetation (grassland/shrubland/forest) (20-50%) 140 Closed to open (>15%) herbaceous vegetation (grassland savannas or lichens/mosses) 30 Mosaic vegetation (grassland/shrubland/forest) (50-70%) / cropland (20-50%) 150 Sparse végétation Legend 40 Closed to open (>15%) broadleaved evergreen or semi-deciduous forest (>5m) 160 Closed to open (>15%) broadleaved forest regularly ooded (semi-permanently or temporarily) - Fresh or brackish water 50 Closed (>40%) broadleaved deciduous forest (>5m) 170 Closed (>40%) broadleaved forest or shrubland permanently ooded - Saline or brackish water 60 Open (15-40%) broadleaved deciduous forest/woodland (>5m) 180 Closed to open (>15%) grassland or woody vegetation on regularly ooded or waterlogged soil - Fresh brackish or saline water 70 Closed (>40%) needleleaved evergreen forest (>5m) 190 Arti cial surfaces and associated areas (Urban areas >50%) 90 Open (15-40%) needleleaved deciduous or evergreen forest (>5m) 200 Bare areas 100 Mosaic forest or shrubland (50-70%) / grassland (20-50%) 210 Water bodies 110 Mosaic forest or shrubland (50-70%) / grassland (20-50%) 31 The diagram of the edge of the cuirasse plateau (figure 8) describes • The plateau of Dalaba is separated from the plateau of Labé by LAND COVER a landscape that is typical of the Fouta Djallon. On the Bowal’s sur- the upper Kokoulo valley. With an average altitude of 1,100 m face, vegetation is scrubby and conducive to grazing and logging. between Bouliwel and Dalaba, these plateaus culminate around LAND COVER OF THE FOUTA DJALLON These almost impermeable surfaces only make water flow possible Diaguissa, at a height of 1,425 m. Bauxite cuirasse outliers punc- HIGHLAND’S EXTENDED AREAS BASED ON THE under the surface of the cuirasse’s edge. Logging activities are thus tuate this eastern escarpment. To the west, it reveals sandstone hills, GLOBCOVER 2008 PROJECT much more detrimental to these surfaces, and the increased degra- testimonies of its decline due to erosion. dation of these spaces can lead to erosion during heavy rains. The • The plateau of Mali-Yambéring and the Mali escarpment: This pla- IN THE RESTRICTED EXTENDED AREA OF THE FOUTA DJALLON most suitable cultivation areas are located on the slope rises, where HIGHLAND’S RPID teau, with an altitude comprised between 1,100 m and 1,400 m, soils are more hydromorphous in nature (spotted area) due to the culminates at Mount Loma (near Mali), a mountain which is a dole- In the restricted area of the Fouta Djallon highland’s RPID, the land associated water tables that can be found there and due to water rite sill and not an indurated outlier. It is not massive and alternates cover associated with shrubby savannah has quite similar propor- movement in the ground. between little cuirasse plateaus and dolerite sills that are particular- tions to the Fouta Djallon topographical highland (40%) with a more ly numerous in that sector. In the north of Mali, the escarpment rises HIGH PLATEAU OF FOUTA DJALLON marked spatial distribution in the Upper Guinea plains to the East- more than 1,000 m above the rise (slope of Madina-Kouta). To North-East of the Fouta Djallon highland (map 13). Nearly 30% of the From the point of view of its geography and geomorphological the west and northwest, the escarpment is less steep and displays surface area in this zone is associated with “open forest” type trees or shape, the entity of the Fouta Djallon highland is more specifically intermediate flats or steps. wooded vegetation. The patches of vegetation distributed between recognizable (map 14) in the central part of the highland. Morpho- logical sub-units can be found in these high plateaus, such as: • The Mamou Highlands are born of the extension of the Diaguis- tree, shrub, prairie and crop vegetation covers 31% of the surface sa-Dalaba plateau which constitutes, according to Boulvert, the area in this zone and are largely in the Kindia - Fria - Boké zones • The plateau of Labé (approximately 1,100 m) with a central part south end of the Fouta Djallon plateaus. Landforms do not reach (Guinea coastal highland sector). This land cover is less pronounced that is massive and tabular. This plateau extends toward Dabola, 1,100 m in height, and the cuirasse interfluves are most often dis- in the North-East part of the Fouta Djallon highland, although it is and it is marked by dolerite intrusions. Encrustation is generalized mantled and limited. visible in the Siguirini sector. Finally, a class associated with the man- with, in particular, outliers of the primary bauxite surface called grove forest would appear at a proportion of nearly 0.1% in the Labé (P. MICHEL,1973). Two flats rises around Dankolo which mark coastal fringe of this extended area. the transition with the plateau of Tougué. IN THE WIDER EXTENDED AREA OF THE FOUTA DJALLON Figure 8 > Edge of lateritic plateau (from Demangeot - 1976) HIGHLAND’S RPID Bowal The proportions between shrubby savannah and cover associated B A with open forest and wood (41% and 21% respectively for this extended area) are like the previous zones, although the forest cove- Backwater smooth slope rage is a little lower. The major difference between the land cover here and other spaces is the appearance of rain-fed cultivation areas (or D C low-land cultivation) dominant in the extreme north-east of the zone, beyond Bamako (map 13), which represents 3.6% of the land cover E F for this space. Finally, the artificial lakes caused by the Manantali dams, the Sélingué, Baneah and Garafiri dams and the free water surface area constituted of major rivers (Niger in particular) represent a little over 0.5% of the total RPID extended surface area, i.e. around 1,550 km². G Bedrock H GEOMORPHOLOGICAL MODEL OF THE FOUTA DJALLON LANDSCAPES circulation of water The plateaus and glacis are the main geomorphological features of the Fouta Djallon highland. Maignien (1958) and Michel (1973) iden- tified three major crust levelling surfaces with successive steps, an A : Bowal, lateritic surface of relative accumulation, more or less cracked E : Cemented surface shaped in glacis intermediate crust relief of average altitude on the slopes and finally B : Edge of Bowal with screes F : Termite mound three very variable extended glacis. C : Spotted zone G : plain with backwater D : Groundwater circulation between lateritic surface and spotted zone H : absolute accumulated lateritic surface BOWAL : The term bowal (a bowal/several bowés) is a Peulh word. It is given to forms made of laterite surface crusts, once released by erosion. The first use and explanation of this term was by the geographer Jacques Richard-Molard in 1944 when describing Fouta Djallon Highlands in Guinea. Since then, the term has entered various dictionaries and entered French in geomorphological vocabulary and German in biogeography. FOUTA DJALLON HIGHLAND WATER ATLAS • THE PHYSICAL ENVIRONMENT OF FOUTA DJALLON AND ITS EXTENDED AREA MORPHOPEDOLOGICAL ENTITIES ASSOCIATED TO FOUTA this entity,we can see a shape with two large steps, with a slope-flat SURROUNDING HIGH PLATEAU OF FOUTA DJALLON DJALLON PLATEAU (Kolenté Piedmont) topped by sandstone plateaus. The following morphopedologic landscapes can be identified around The following morphopedological sub-units are associated with the • The Bassari Mountains, also identified as the Coniagui Highlands, the Fouta Djallon: Fouta Djallon represent the transition between the Fouta Djallon highland and • The sandstone plateau of Kindia - Télimélé, which more or less cor- • The plateau of Tougué-Timbo is made up of the upper basins of the Tominé Piedmont. They are a set of small hills lined up like a responds to the Bové basin described by geologists. This plateau, the Gambia, Bafing and Tinkisso rivers. Encrustation is generalized chain. Active erosion uncovers rockbands in a SSW-NNE alignment. at a lower altitude, is composed of a complex alternation of coarse and the plateau appears massive and monotonous with a succes- • The Tominé Piedmont (or the Gaoual-Koundara Piedmont or the layers (sandstone and conglomerates) which is sometimes conducive sion of plateaus and cuirasse rises. Nonetheless, it is more or less Youkounkoun basin) constitute a vast flattened area with an alti- to induration. dismantled by the vertical erosion of the Tinkisso and Bafing rivers. tude of 100 m. The valley widens to a breadth of approximately • The transition of the plateau of Bové with the sandstone plateau oc- In the north, this plateau ends at the Guinea-Mali border, whereas one hundred kilometers, like a fan delta. Historically associated curs in multiple tiered cuirasse steps. This plateau is vertically eroded in the south, between the Mongo and the Tinkisso Rivers, Mount with the Fouta Djallon highland, this sub-unit remains very far from by waterways but it retains a well established cuirasse surface. Tandon (1,015 m) marks the southeast border of the Tougué-Tim- the geomorphology of the heart of the Fouta Djallon (Boulvert, bo plateau. It is connected to the Mamou Highlands on its western • The Manding plateau, which is composed of a tabular relief fossilized 2003). Passage from the Bassari Mountains to this sub-unit involves side. by encrustation. It dominates the southern edge of the Taoudéni ba- a cuirasse slope that is virtually continuous over 50 km from Gaoual sin. • The Rises - Flats of Linsan or of the Upper Konkouré River are to Kifaya. an area of transition between the Fouta Djallon highland and the • The indurated slope of Faranah is covered by a generalized encrus- • The Badiar sandstone plateaus dominate the Tominé Piedmont. plateau of Kindia. This sector is a depression which overlooks the tation and there are several outliers that can be reconciled with the This landscape is described as a «sort of ovoid sandstone pan- basins of the Kolenté and Kora rivers to the south. With an altitude dismantling of the plateau of Tougué. cake» which stretches to the southwest beyond the border with of approximately 500 m, it takes the form of a cuirasse rise that is Guinea Bissau. homogeneous and vertically eroded by the Kolenté River. Within Paysages morphopédologiques Map 14 > Morphopedological de Guinée landscape of Guinea -14.0 Highland of Coniagui -10.0 BAMAKO -16.0 Kedougou piedmont -8.0 Badiar Piedmont Tomine Northern escarpment of Mali piedmont BISSAU MALI Bakoye 12.0 carve GAOUAL Manding plateau KOUBIA LELOUMA TOUGUE LABE SIGUIRI DINGUIRAYE Sandstone Tougue plateau PITA plateau BOKE 11.0 of Kindia Bowé plateau DABOLA DALABA KOUROUSSA Indurated glacis of Siguiri Bo a piedmont FRIA KANKAN MAMOU Indurated glacis of Faranah High plateau of Fouta Djallon KINDIA FARANAH 10.0 Mangrove Linsan CONAKRY plateau Pre forest area of Kaba piedmont Kissidougou - Beyla KEROUANE Indurated glacis Forécariah piedmont of Senko 9.0 on bedrock Granitic highland -12.0 of Macenta Projection latitude - longitude WGS 84 -NBA, Ministry of environment of Guinea - Created by Géohyd Anteagroup - Luc Ferry & Axel Aurouet 2017 BEYLA 33 MAJOR CLIMATE FEATURES THE SUDANO-GUINEAN CLIMATE, WHICH IS DOMINANT IN GUINEA, MARKS A TRANSITION BETWEEN A VERY HUMID CLIMATE OBSERVABLE IN THE SOUTH AND A DRYER «SUDANESE» CLIMATE TO THE NORTH. THE FOUTA DJALLON CLIMATE IS DIFFERENT FROM THE SUDANO-GUINEAN CLIMATE DUE TO ITS «MOUNTAINOUS» AND MUCH COLDER NATURE. ANNUAL RAINFALL AVERAGES 1,700 MM IN THE FOUTA DJALLON A CLIMATE INFLUENCED BY THE INTERTROPICAL CONVERGENCE ZONE Zone de Map 15 convergence > Intertropical intertropicale Convergence Zone (ITCZ) (ZCIT) AND THE GUINEAN HIGHLANDS 0.00 20.00 Topographic highland The Inter-Tropical Front (ITF), now more commonly known as the of Fouta Djallon Tunisia Intertropical Convergence Zone (ITCZ), is a major feature of the climate in Guinea, the Guinea surrounding area and more generally West Africa. This “real front” (map 15) is a discontinuous surface Morocco between the continental tropical air mass, hot and dry, and the maritime monsoon tropical air mass, fresh and humid. Its movement Algeria is slow and is coordinated by an annual seasonal movement. In Ja- Lybia nuary, it is at its most southern point (a little north of Conakry) and Egypt in August at its most northern position (Nouakchott NE position towards the 20th parallel). These North-South movements during the southern and northern summers generate alternate dry and humid periods in the sub-region characterizing the seasons in this part of the world. More locally in the Guinea surrounding area, Mauritania 20.00 July three major climate regions are described by Aubréville (1949). The Forest Guinea climate region including Sierra Leone, Liberia Mali i on in and Forest Guinea, the Sudan-Guinea region, which includes the centre of the Fouta Djallon highland and the majority of Guinea, Posit Niger Chad and finally the Sudan-Sahelian region, starting at the Northern Senegal edges of Guinea. In view of previous knowledge, these major re- The Gambia Sudan Burkina Faso gions are further explained by Boulvert (1992) who suggests even Guinea Bissau narrower sub-divisions. Guinea Benin Nigeria Sierra Leone Ghana in January Ivory coast Togo tion Central African Republic Posi Liberia Cameroon 0.00 Projection latitude - longitude WGS 84 - Géohyd - topographic highland from L. Ferry, 2017 - Created by Géohyd Anteagroup - Axel Aurouet 2017 FOUTA DJALLON HIGHLAND WATER ATLAS • THE PHYSICAL ENVIRONMENT OF FOUTA DJALLON AND ITS EXTENDED AREA TEMPERATURES AND EVAPOTRANSPIRATION lower altitude and temperatures there. This is notably the case in the Fouta Djallon highland. The PET maximums are observed du- TEMPERATURES INFLUENCED BY THE FOUTA DJALLON ring the hottest month (March to the south of the country and the HIGHLAND Fouta Djallon highland), when the sun is at its peak. For this month, The average annual temperatures follow a growing progression the PET is assessed at 174 mm in Conakry and 171 mm in Dalaba. from the south to the north (Map 16), alongside the reducing rainfall. This reducing “axis” is however skewed in Guinea, with the appearance of the Fouta Djallon highland’ and the Guinean Dorsal. On the eastern edges of Guinea, temperatures change “normal- ly” on a South-North axis of 24.5 °C on average at N’Zérékoré at September nearby Mamou 28.2 °C in Bamako, passing through 26.1 °C in Kankan and 26.8 °C in Siguiri. Next, the average temperatures above 27 °C are only Température moyenne Map 16 > Mean annual annuelle temperature in West Africa observed in the north-west (27.2 °C in Boké and 27.9 °C in You- kounkoun) and the north-east of the country. At the level of the -15.00 -10.00 Fouta Djallon highland’ and Guinean Dorsals’, the average annual 15.00 SE temperature falls below 25 °C and settles around 21°C in the Fouta DAKAR N EG A Djallon highland (20.9 °C in Dalaba). During the warmest months L (March south of the 9th parallel and April-May to the North), the temperatures in the north of the country are easily above 30 °C GAMBIA (Youkounkoun, Siguiri). In Fouta Djallon, the temperature in the BANJUL G warmest month is around 24  °C. The coolest months are obser- N FALE M E BA F I ved during the winter period in July-August in the Fouta Djallon highland, settling around 18 to 19 °C (Dalaba, Mali). It is also during BAMAKO RUBA R this same period that the coolest months are observed in the South CO GE NI L RIO of Guinea and the Forest Guinea area (22.8 °C in Beyla). Further BISSAU North, the coolest month tends to be observed in December-Ja- nuary, along Guinea-Bissau and the upper basins of the Gambia, Senegal and Niger (up to Macenta). Boulvert notes out of curio- sity that the absolute minimum temperature in Guinea would have been recorded In January 1906 at the sources of the Niger at 1 °C. A 10.00 EVAPOTRANSPIRATION OR THE QUANTITY OF WATER T GOING BACK INTO THE ATMOSPHERE CONAKRY ES CI L AR Evapotranspiration covers the notion of evaporation, represen- SC ting the quantity of water transformed into vapour due to the A N temperature and wind, and the notion of transpiration linked to T FREETOWN a plant’s demand for water. This fundamental climate parameter in Highland of Coastal I WA the understanding of hydrological and hydrogeological balances A Guinea MO SE C is expressed in millimetres of water evapotranspired. We can also distinguish the notion of potential evapotranspiration (PET, cor- SANDRA O responding to a climate demand for water vapour) and actual Topographic highland of C evapotranspiration (AET), which includes the actual availability Fouta Djallon E of water to be evapotranspired (including the water component A MONROVIA SAS LY in the soil). In the Guinea and surrounding Guinea geographic N VA L CA area, this PET varies from 1300 mm at the 7th parallel in Liberia Topographic highland to 2000 mm at the 13th parallel in Mali. The Guinea coasts cause a of Guinean Dorsal Legend skew from the South-west to the North-east with a PET assessed at 5.00 Te m p e r a t u r e i n ° C 1410 mm in Conakry and 1900 mm in Niagassola, near to the Mali border. The lowest PET values in Guinea are observed in N’Zéré- 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 koré (1322 mm in the forest area), the PET also decreases with the Projection latitude - longitude WGS 84 - PRAI - MFD, FAO, Géohyd - Topographic highlands from L. Ferry, 2017 - Réalisation Géohyd Anteagroup - Axel Aurouet 2017 35 CLIMATE THE CLIMATE TYPE OF THE FOUTA DJALLON HIGHLAND AND ITS EXTENDED AREA (FROM Y.BOULVERT – 2003) Regional rainfall (map 17) shows that there are pronounced rainfall contrasts in the extension area of the Fouta Djallon highland, and more generally in the sub-region. There are thus three major climate areas concerned by the extended area, which can themselves be subdivided into sub-sectors. Climate « Guinean Forest » 400 18 Mean daily and monthly rainfall THE CLIMATE AREA OF FOREST GUINEA AND THE GUINEAN DORSAL Kissidougou 16 350 This area is initially separated from the Sudan-Guinea area by a line the Sierra Leone climate corresponding to the maritime district of 14 linking Freetown (Sierra Leone) to Ouré Beka (Guinea) along the Scar- Sierra Leone with abundant rainfall (2,500 to 4,000 mm/year), rainfall 300 cies (or Kaba) then, forming a bend, by linking Ouré-Kaba to Touba peaks in August-September and dry months in January-February un- monthly rainfall in mm daily rainfall in mm 12 250 (Ivory coast) by passing through Beyla (eastern edge of Guinea). This der the influence of the Harmattan; the Guinean Dorsal sub-climate 10 large climate region which covers the dense and damp forest is cha- (figure 9), under the influence of the highland (Nimba mountains, 200 racterised by very uniform temperatures (24 to 27 °C with 4 °C ther- Simandou mountains...) is characterised by slightly lower tempera- 8 mal range) and its humidity. The rainfall is high with the heart of the tures (between 22  °C and 29  °C), slightly lower rainfall (1,800 to 150 6 rainy season in July-August on the coastal slope and in September in 3,000 mm) with a peak during September, secondary peaks in June 100 the Guinean Dorsale. Very exceptionally, minimum temperatures are or July and a significant drops in other months. Finally, a final sector 4 observed in December (Macenta) and even in January (Kolahun in corresponds to the Edge of the dense Guinea forest and the Guinea 50 2 Liberia). This climate region can be subdivided into four sub-areas. surrounding area savannah sectors. This extends from Freetown to Boulvert (op. cit.) notably distinguishes the Liberian sub-climate (only Touba via Musaï and Kérouané. 0 Day / month on one year 0 seen in Liberia and to the south of the 7th parallel) which is cha- Figure 9 > Rainfall of «Forest Guinea» climatic domain racterised by no dry months with a net slowing of rain in August; Climate « East Guinea » 400 18 Mean daily and monthly rainfall Kankan - THE SUDAN-GUINEA AREA, THE HEART OF GUINEA AND THE East Guinea sub-climate 350 16 FOUTA DJALLON HIGHLAND The “typical” Eastern Guinea climate (figure 10) is characterised by a 300 14 Bordered to the South by the Forest Guinea climate region, the Su- fringe stretching from the West to East between the 9th and 12th pa- dan-Guinea region is bordered by the Sudan-Sahalian area to the rallel, starting with the Eastern foothills of the Fouta Djallon highland monthly rainfall in mm daily rainfall in mm 12 250 north by a line passing through the Bolama-Bafata axis (Guinea-Bis- (Tougué-Kédougou in Senegal) and extending to the East, surroun- 10 sau) up to the Gambia then generally following the Guinea-Sene- ding Kérouané to the South and Siguiri to the North. This climate is 200 8 gal-Mali border, joining the Sankarani-Niger confluence in Mali. This found in the upper basins of the Gambia, Senegal (Bafing) and Niger. 150 region is characterised by several rainy months (over 100 mm rainfall) The average temperatures vary between 23.5 °C and 27.7 °C with a 6 for 5 to 7 months with dry months (rainfall under 30 mm) between 4 relatively small thermal range between 4.4 °C and 6.7 °C. The average 100 4 and 5 months. This climate region can be subdivided into three sub- rainfall decreases along a SSW-NNE axis. The month with the highest areas. In addition to a sub-climate “typical of Eastern Guinea”, there rainfall is generally August, sometimes delayed into September. The 50 2 is also a Fouta Djallon sub-climate (see dedicated chapter) and the rainfall starts in April and stops suddenly in November. Evapotranspi- 0 0 Maritime Guinea sub-climate. ration varies between 1640 mm (Tougué) and 1900 mm (NE of Si- Day / month on one year guiri) with 120 to 176 d/year during when rainfall is higher than eva- Figure 10 > Rainfall of «East Guinea» climatic domain potranspiration (positive water balance). FOUTA DJALLON HIGHLAND WATER ATLAS • THE PHYSICAL ENVIRONMENT OF FOUTA DJALLON AND ITS EXTENDED AREA Climate « Marine Guinea » 1400 Mean daily and monthly rainfall 60 Conakry Maritime Guinea sub-climate CLIMATE AT THE HEART OF FOUTA DJALLON, AN UNUSUAL FEATURE OF THE SUDAN-GUINEA CLIMATE The Maritime Guinea Sub-Climate (figure 11)is very largely under the influence of the intensity of the Gulf of Guinea monsoon and This “Fouta” climate (figure 12), individually explained by Boulvert, extends from the North-West of Sierra Leone to the South-East of corresponds to the Fouta Djallon Highland and has a limited geogra- Guinea-Bissau. The contrast between the dry and rainy seasons is phic extension from the Sierra Leone border to the South up to the 1200 accentuated by the effect of the rain which appears suddenly in Tamgué mountains (towards the Loura mountains) to the North. It is 50 May, gets stronger in June to culminate in August and finally dimini- described as a mountain climate of the Sudan-Guinea area. However, shes in September and stops in November. The rainfall is abundant it is intensely watered by monsoon rains and is subject to the drying (1934 mm in Gaoual, 2270 mm in Télimélé, 3 221 mm in Boffa and influence of the Harmattan, whilst fog moderates dryness. In Mali, 4351  mm in Conakry) with a SE/NW decrease mainly linked to a with the altitude, the annual averages fall below 24 °C down to 20 °C. more continental influence to the North-West. This continental ef- The coldest month (December) normally noted in the Sudan-Guinea fect is also felt on evapotranspiration which is presented inversely area is observed in August at the summits in Dalaba and Mali (around 1000 to rainfall with a decrease on the NW-SE axis (1,411 mm in Conakry, 18 °C). Under this climate, the hottest months are modest in tempe- 1,529 mm in Boffa, 1,584mm in Télimélé and 1,733 mm in Gaoual). A ratures (between 23 °C and 26.5 °C) and run from March-April. The 40 sub-division of this climate can be bordered by an approximate line thermal ranges are small during the year. The average annual rainfall is between Télimélé - Fria and Conakry to individualise a Conakry-Té- relatively high, around 1800 mm in Mali and 2250 mm in Dalaba, with limélé-Forécariah sub-climate and a Boffa-Boké-Gaoual sub-climate. a decrease due to the wind (1714 mm in Labé, 1590 mm in Ditinn). Between these 2 sub-divisions, there is a slightly shorter dry season The first rains reach Dalaba in March, Pita in April and Mali in May. 800 in the Conakry sector with rainfall divided in half between the Co- The maximum rainfall is observed in August with a return in October monthly rainfall in mm daily rainfall in mm nakry region and Guinea-Bissau border. The number of days where and some extra rainfall on highland in December. Evapotranspiration rainfall is higher than evapotranspiration is significant: 177 to 198 d/ remains quite high, at around 1450 to 1625 mm. During 154 to 185d/ year for Conakry-Télimélé and 155 to 172 d/year for Boké-Boffa. year, rainfall is higher than evapotranspiration (positive water balance). 30 600 20 Climate « Fouta Djallon » 400 400 Mean daily and monthly rainfall 18 Labé 350 16 14 300 monthly rainfall in mm daily rainfall in mm 12 250 10 10 200 200 8 150 6 100 4 50 2 0 0 Day / month on one year 0 0 Day / month on one year Figure 11 > Rainfall of «maritime Guinea» climatic domain Oceanic facade in Guinea Figure 12 > Rainfall of «Fouta Djallon» climatic domain 37 CLIMATE Climate « Sudan » 400 Mean daily and monthly rainfall Tambacounda TOWARDS THE NORTH OF THE FOUTA DJALLON HIGHLAND, FROM THE SUDAN CLIMATE TO SUDAN-SAHELIAN CLIMATE 350 18 16 This climate region is positioned on the northern fringe of Guinea the Guinea-Bissau-Casamance and Upper Guinea sub-sector. Upper 300 and reaches from West Africa (Senegal) to the Horn of Africa (Eritrea) Gambia has lower rainfall (> 1000 m vs 1100 to 1500 mm Guinea Bis- 14 monthly rainfall in mm with a clearly marked “continental” type. The specific feature of this sau-Casamance) as well as higher evapotranspiration (>1800 mm vs daily rainfall in mm 250 12 Sudanese climate region is the fact that there are less rainy months 1800 mm Guinea Bissau-Casamance). Finally, to the north of Guinea, 200 10 than dry months (map 14). Boulvert proposes five sub-climates. on the fringe including Bamako in Mali, the climate sector is linked The Sudan-Sahelian Southern variations (Youkounkoun-Kédougou) in reality to the continental Sahelian-Sudan climate marked by high 8 150 and the Banifing basin (South-East of Mali) are two very different average temperatures (> 28 °C on average with peaks higher than 6 sub-groups which are transition sectors between the Sudan-Guinea 32  °C in April-May), relatively low rainfall (1200 mm) and marked 100 4 and Sudan-Sahalien areas. The rainfall varies there between 1100 evapotranspiration (>1850 mm). 50 sometimes to 2000  mm (Youkounkoun-Kédougou) for an eva- 2 potranspiration between 1700 mm and 1900 mm. To the west of 0 Day / month on one year 0 the Youkounkoun sector, there is a “lower Casamance” climate sub- group where the maritime influence can be felt. It is made up of Figure 13 > Rainfall of «Sudanian» climatic domain View on Coastal Guinea highland, near Kindia FOUTA DJALLON HIGHLAND WATER ATLAS • THE PHYSICAL ENVIRONMENT OF FOUTA DJALLON AND ITS EXTENDED AREA Pluviométrie rainfall forannuelle moyenne Map 17 > Mean annual sur la période 1959 - 1981 1959-1981 period from l’Hote D’après / From l’Hôte et Mahé & Mahé 1995 -20.00 50 -15.00 -10.00 -5.00 0.00 TIDJIKDJA NOUAKCHOTT 200 10 0 PODOR TOMBOUCTOU SAINT-LOUIS GAO 400 MATAM 3 00 500 BAKEL NIORO DU SAHEL 15.00 DAKAR DIOURBEL 70 0 MOPTI TAMBACOUNDA 800 600 BANJUL SEGOU 10 0 0 KITA KOLDA KOULIKORO OUSSOUYE KOUNDARA OUAGADOUGOU BAFATA 1500 MALI BAMAKO KOUDOUGOU BISSAU SIGUIRI 1 1 00 100 BOLAMA 130 SIKASSO 0 900 14 0 Topographic highland PITA 00 BOBO-DIOULASSO of coastal Guinea MAMOU KANKAN 12 00 GAOUA A 10.00 3 200 0 18 0 0 50 T CONAKRY BOUNDIALI 0 KISSIDOUGOU BOUNA L DAMONGO MAKENI 25 BEYLA 00 2500 A FREETOWN KATIOLA N MANO KENEMA Legend Topographic highland 30 00 150 T 00 000 12 Rainfall class of Fouta Djallon 11 0 0 2 I 400 0 0 0 < 100 mm 0 13 KUMASI 14 C 00 YAMOUSSOUKRO 100 - 400 mm O MONROVIA 18 0 400 - 600 mm 0 C BUCHANAN 1400 00 600 - 800 mm E Topographic highland 18 0 0 00 1 0 800 - 1000 mm A of Guinean Dorsal 1600 ACCRA 11 2 200 2 00 GREENVILLE 1000 - 1500 mm N ABIDJAN 0 1500 - 2000 mm 2000 - 3000 mm > 3000 mm Projection latitude - longitude WGS 84 - Géohyd - topographic highlands from L. Ferry, 2017 - Mean annual isohyetes from 1951 - 1989 from l’Hôte & Mahé IRD, 1995 - Created by Géohyd Anteagroup - Luc Ferry & Axel Aurouet 2017 39 HISTORICAL TREND IN RAINFALL AND CURRENT TRENDS ANNUAL RAINFALL AVERAGE IN THE FOUTA DJALLON HIGHLAND HAS DECREASED BY CLOSE TO 12% BETWEEN 1930-1960 AND 1970-2000. THIS TREND, GENERALIZED IN WEST AFRICA AT THE TIME, HAS REVERSED SLIGHTLY OVER THE PAST FIFTEEN YEARS WITH INCREASED PRECIPITATION IN COMPARISON WITH THE DROUGHT OF 1970-1990. A MAJOR WIDESPREAD HISTORIC DROUGHT A REGULAR DEFICIT IN THE HIGHLAND AND 1922 to 2001, at the Fouta Djallon highland itself, the Pita station has the 9 driest years.. The Labé station shows 7 out of the 10 driest IN WEST AFRICA SINCE 1970 ITS FRINGE SINCE THE 1970’S years for the 1970-1989 period and the evaluation of its rainfall in- Deep-rooted trends on rainfall in West Africa and Central Africa This period of drought in West Africa is shown in rolling 30-year dex between 1923 and 2007 (figure 15) clearly shows the impact of were observed from the 1990s when distinct rainfall variations rainfall studies at LABE, MAMOU, SIGUIRI, BAMAKO (Mali) and this drought in the Fouta Djallon Highland. were demonstrated for the 1950-1990 period (Mahé et al., 2005; KEDOUGOU (Senegal) (table 4). At the centre of the Fouta Djal- Descroix et al., 2009; Dezetter et al., 2010). After a rather rainy period lon, in Labé, the normal 30-year situation has moved from 1693mm observed for the 1950-1970 period, a very dry period followed (1931-1960) to just 1475 mm (1971-2000), a 13% fall from the nor- (1970-1995), which is still well remembered. This “great drought” mal situation. This drop is the same (12%) as at Mamou, falling from seems to start around the 1968-1971 period with the phenomenon 1948 mm for the 1931-1960 period to 1722mm for the 1971-2000 spreading across the African Sudan-Sahelian fringe. During this period. To the North and East of the Fouta Djallon highland (Kedou- period, rainfall deficits were assessed between 25% (Liberia and gou and Siguiri), the intensity of the falls is around 9 to 10%, falling Senegal-Gambia) and 13% (Sierra Leone). In Guinea, the overall from a standard of 1299.8 mm (1931-1960) to 1174.4 mm (1971- deficit for this period can reach the upper range (20%), as well as 2000) at Siguiri, and falling from the standard for the same period in Mali (23%), Guinea-Bissau (22%) and the Senegal-Gambia sector from 1264 to 1153.2mm at Kedougou. Finally, moving away from (25%). Against more recent data, a North-South gradient is observed the Fouta Djallon highland, at Bamako, the normal situation has fallen in annual variations with deficit fluctuations not exceeding 20% in the by nearly 19% from rainfall of 1127.7 mm (1931-1960) under the Senegal Guinea basin, with deficits reaching 35% in the Mali basin emblematic threshold of 1000 m to around 910 mm (1971-2000). (1983) and with deficits reaching nearly 60% in Mauritania. Between 1970 and 1984, across the period for usable data from Table 4 > Trend of mean thirty-years rainfall in West Africa between 1931 and 2000 ( JC Bader) AVERAGE ANNUAL RAINFALL OVER 30 YEARS IN MM DIFFERENTIAL FOR LOCALISATION COUNTRY PERIOD 1931-1960 1931-1960 1941-1970 1951-1980 1961-1990 1971-2000 AND 1971-2000 LABE GUINEA 1,693.0 1,677.8 1,649.8 1,530.1 1,475.0 -13% MAMOU GUINEA 1,948.3 1,954.2 1,958.1 1,802.3 1,721.7 -12% SIGUIRI GUINEA 1,299.8 1,326.1 1,319.2 1,230.5 1,174.4 -10% KEDOUGOU MALI 1,264.0 1,266.9 1,282.1 1,178.8 1,153.2 -9% BAMAKO MALI 1,127.7 1,112.2 1,062.7 949.9 910.6 -19% KAYES MALI 799.7 768.5 695.4 630.9 615.5 -23% KENIEBA MALI 1,340.0 1,335.4 1,291.5 1,153.1 1,083.6 -19% KITA MALI 1,159.9 1,091.3 1,055.8 920.3 898.8 -23% NIORO DU SAHEL MALI 626.1 603.9 563.5 454.7 427.7 -32% YELIMANE SENEGAL 616.8 604.8 564.2 477.8 445.3 -28% BAKEL SENEGAL 505.9 518.0 503.2 499.1 481.0 -5% FOUTA DJALLON HIGHLAND WATER ATLAS • THE PHYSICAL ENVIRONMENT OF FOUTA DJALLON AND ITS EXTENDED AREA A RETURN OF RAINFALL IN RECENT YEARS? The drought described previously and covering the period 1970- ger), it seems more pronounced, franker and more sustained whereas 1990 with a “peak” in the 1980s was more or less uniform across the it does not seem to affect it inside the Sahel. Based on rainfall indexes majority of West Africa. Nevertheless, the recent period seems to focused on agricultural criteria, it is important to underline that this be characterised by more complex systems. At the Sahelian fringe return of rainfall does not necessarily match up with the agro-climatic (between the 11th and 16th North parallel), there seem to be more season. This is particularly true in the central part of the Sahel where contrasted dynamics where the Eastern Sahel (around 10 °E longi- there are years without organized agricultural monsoon in the 2000s, tude) has more rainy conditions since 1990, returning to the average whereas rainfall did not change in this period. This observation tends levels for the 1950-1989 sequence. The Central Sahel saw a decline to show the intra-annual modification of the temporal rainfall distri- in the drought whilst remaining at rainfall levels lower than those ob- bution. These “failed monsoons” based on the Sikavumar criteria are served for the 1950-1989 sequence and the western Sahel continues more adapted to the Sahel, logically decreasing on a North-South to experience persistent dry periods whilst remaining at the average axis and the Sudan zones, to the northern fringes of the Fouta Djallon levels seen in the 1970-1989 sequence. For the western Sahel sector, highland, with no “failed” seasons since 1951 (Kedougou and Kolda Descroix (2015) seems to demonstrate a return to the rainfall depth, stations in Senegal a little under 13°N latitude). notably showing an increase in the number of rainfall days with strong accumulation and an earlier arrival of the rainy season, whilst the end of the monsoon period does not seem to have changed. These re- Mabé’s mountain on sandstone, Télimélé. In the foreground, Elaeis guineen- cent studies also underline that whilst the returned rainfall reached sis and Terminalia glaucescens the West (Senegal/Gambia) more than the Central Sahel (Middle Ni- Figure 14 > Rainfall Standardized Index at Labe Station Precipitation Index and annual rainfall at Labe (heart of Fouta Djallon) between1923 and 2007 2500 Rainfall in mm 2.5 2 Annual rainfall in mm Standardized precipitation index 2000 1.5 1 1500 0.5 0 1000 -0.5 -1 500 -1.5 The Standardized precipitation index de nes the severity of the drought compared to a reference. Negative annual values indicate a drought compared to the selected reference period and positive value indicate a wet situation. Values between 1 and 2 characterize a "high humidity" situation while values between -1 and -2 -2 characterize a situation of "strong drought". Behind -2 the drought is extreme. Standardized precipitation index 0 2007 1923 1925 1927 1929 1931 1933 1935 1937 1939 1941 1943 1945 1947 1949 1951 1953 1955 1957 1962 1964 1966 1968 1970 1972 1974 1976 1978 1980 1982 1984 1986 1988 1990 1992 1994 1996 1998 2000 2002 2004 41 SUMMARY OF PHYSICAL LANDSCAPE The Fouta Djallon highland are a singularity in the sub-region’s relief. With a surface area of These highlands play a fundamental role in rainfall distribution on a regional scale. Both the 47,000 km², they are defined (L. Ferry, 2017) as the Central Guinean Highlands located above Fouta Djallon highland and the Guinean Dorsals act as a real topographic barrier, and they de- a 440 m altitude. They stretch slightly into Mali and Sierra Leone along their borders. The Fouta termine the rainfall pattern that ranges from close to 4,000 mm per year in Conakry to almost Djallon highland is surrounded by other topographic highlands, the most emblematic of which 1,300 mm per year on the northern border of Guinea (some 400 km away). These highlands are the Guinean Highlands located to the East-Southeast of the Fouta Djallon. With a surface can be considered as having helped to mitigate the effects of drought on the southern fringe area of 89,000 km², beyond Guinea, these also concern Sierra Leone, Liberia and Côte d’Ivoire. of the country during the 1970-1980 drought which impacted West Africa, even if the Fouta The other surrounding highlands defined by L. Ferry are the coastal Guinea mountains, the Djallon highland was not spared said drought. highland of the Siguirini-Baléa region and the Manding Mountains, which are all three exten- sions of the Fouta Djallon highland. Originating from a very old geology, the Fouta Djallon highland, like other neighboring moun- tains, is all marked by the presence of predominantly acid rocks. The rocks of the Fouta Djallon All of these highlands which characterize the region’s landforms play a major role in the origins highland are essentially sandstone with dolerite injections. They stand out quite clearly from the of the great rivers. The most emblematic of them are the Niger River - which has many upstream granites of the Guinean Highlands. affluents that originate in the Fouta Djallon highland or in the Guinean Highlands - the Senegal River - which originates simultaneously in the Fouta Djallon highland, in the highland of the In the Fouta Djallon highland, the landscape is made up of terraces consisting of primarily late- Siguirini-Baléa region, and in the Manding Mountains - and, lastly, the sources of the Gambia ritic plateaus, also called Bowal, with savannas and tree vegetation being dominant. Literature River which are almost entirely linked to the Fouta Djallon highland. There is also the Rio Coru- emphasizes the «degraded» nature of these spaces with a reduction of dense forested areas in bal (near Guinea Bissau), the Great and Little Scarcies (near Sierra Leone) and the Konkouré - a the heart of the Fouta Djallon highland. Beyond the Fouta Djallon highland, ecosystems remain river that is entirely Guinean and of paramount importance for the country due to the many rich with a dense and humid forest that can be observed on the relief of the Guinean Highlands hydroelectric developments in its watershed. (Guinea Forest Region) and mangrove ecosystems on the oceanic front. FOUTA DJALLON HIGHLAND WATER ATLAS • THE PHYSICAL ENVIRONMENT OF FOUTA DJALLON AND ITS EXTENDED AREA Cours d’eau Map 18 > et euves Rivers linked en with Fouta lien Djallon avec and highland le massif du surrounding Fouta Djalon, ses extensions et les massifs alentours highlands -15.0 F erlo -10.0 NIORO DU SAHEL Sé 15.0 BAKEL né THIES ga DAKAR l lé ou KAOLACK Ba Gam KOUNGHEUL B a k ye bi TAMBACOUNDA o a BANJUL a ng r m ge G a ou l o u bi Ni K B a KITA Falé m é KOLDA ba KOULIKORO Gé t n ZIGUINCHOR BAMAKO ou KOUNDARA l - Koliba Ga a BAFATA bi ub m Bag o é MANSOA r e Co MALI ng BISSAU Ba r ge GAOUAL Komba Ni To m i n BOLAMA KOUBIA TOUGUE Tinkisso SIGUIRI Ko BOUGOUNI a lé LABE n go é Baou o k K ak r i m n DINGUIRAYE Nu Fié i ran Rio PITA Téné ez oul Sanka o BOKE TELIMELE DABOLA ng K DALABA KOUROUSSA uré Ba r Konk a ige MANDIANA ta l ng o Mil o FRIA MAMOU N KANKAN o Fa a BOFFA Ba K ab Mo KINDIA u n d an di FARANAH Mafo 10.0 K o u ro u k élé DUBREKA s- N ia s rcie e CONAKRY KABALA rci a Di o n ca e Sc Legend KEROUANE ts tl KISSIDOUGOU Topographic highland of Fouta Djallon Gr ea L it k el MAKENI c Topographic highland of Guinean Dorsal Ro BEYLA MACENTA Topographic highland of Coastal Guinea FREETOWN S e wa KAILAHUN Banié - Niandan chain J ong MANO KENEMA Highland of Siguirini - Baléa region r o Mo a NZEREKORE a Mo - S a s s a n d ra ana s Manding mounts l sto C a v ally M Lo Pa u MAN Ce t Highland of Madinani region S ain -15.0 Name of the river Projection latitude - longitude WGS 84 - Géohyd ; FAO- topographic highlands from L. Ferry, 2017 - Created by Géohyd Anteagroup - Luc Ferry & Axel Aurouet 2017 43 WATER RESOURCES OF FOUTA DJALLON AND ITS EXTENDED AREA FOUTA DJALLON HIGHLAND WATER ATLAS TRANSITION TROPICAL REGIMES TOWARDS A PURE TROPICAL REGIME This chapter describes the flows of the main rivers taking their sources from the Fouta Djallon highland, the Guinean coastal highland and the northern descent of the Guinean Dorsal. By proposing this reading, it redefines the main features of the hydrological regimes of the sector’s rivers. It also gives a look at groundwater resources. 45 HYDROLOGICAL REGIMES OF THE FOUTA DJALLON RIVERS HYDROLOGICAL REGIMES OF RIVERS UPON LEAVING THE FOUTA DJALLON ARE CHARACTERIZED BY A HIGH WATER PERIOD FROM JULY TO NOVEMBER, A LOWER WATER PERIOD BETWEEN MARCH AND MAY, AND ABRUPT FLOW CHANGES. THESE REGIMES ARE TYPICAL TROPICAL TRANSITION REGIMES. DOWNSTREAM, A SHORTENING OF HIGH WATER PERIODS CAN BE OBSERVED, BRINGING THE SENEGAL, NIGER AND GAMBIA REGIMES TOWARD BECOMING PURE TROPICAL REGIMES, THEN SAHELIAN ONES. MAJOR FEATURES OF THE SENEGAL RIVER previous regime mainly by a shorter period of high water. Finally, rainfall drought observed during the 70-80s considerably influences the Sahelian regime covers the entire downstream basin of Senegal the average annual flows observed on the Senegal which range from HYDROLOGICAL REGIMES where the rainfall is lower than 700  mm and where the flows are single (220  m3/s 1984-1985 in Bakel) to six-fold (1349m3/s 1936- Senegal is described by Orange (1990) as a pure tropical regime more sporadic. From upstream to downstream, the specific flows de- 1937 in Bakel). Finally, since its creation in 1987, the Manantali dam with a succession of 3 regimes between the sources of the Bafing crease gradually. Downstream, the inputs have barely any influence (on the Bafing in Mali) has modified the river’s hydraulic regime by and Bakel in Senegal: the transition tropical regime, the pure tropi- on the hydraulicity of the Senegal river, the same as the transition limiting downstream flood peaks and by offering low flow support cal regime and the Sahelian regime (Frécaut & Pagney 1982). The tropical regime. Up to Bakel, it is a pure tropical regime, and then during a dry period. In this atlas we will remain on Bakel to look at the transition tropical regime covers the upstream part (Fouta Djallon) of the descent of the Fouta Djallon, which influences the hydraulicity of Senegal, with bakel representing the Northern Fringe of the Fouta the Bafing, the Falémé and to a lesser extent, the Bakoye. This sector the Senegal River. Along the river there is a very strong flow seaso- Djallon highland’ extended area (map 19). enjoys significant rainfall as well as abrupt flow variations linked to nality which marks the flow regime with monsoon rains ( July to Oc- rainfall regimes and the steep gradients of the slopes of Fouta Djal- tober) which cause flood flows and increasingly reduced inputs from lon. The “pure” tropical regime covers the lower part of the Falémé, upstream to downstream. During the dry season, a drying-up regime the Bafing, the Bakoye and the Baoulé. It is differentiated from the is put in place and the associated water tables are emptied. The Daily and monthly mean river ow for Ba ng at Sokotoro - 1972 - 2016 period 120 THE BAFING The Bafing takes the name of the Senegal after its confluence with the every year to be carried over from one season to another. There are Bakoye. The natural year-on-year average flow is currently (1987-2011 three main consequences of these modifications. They currently allow 100 period) around 30 m3/s in Sokotoro, 204m3/s in Daka-Saidou, 235m3/s a good hydraulicity for downstream uses (irrigation, flood recession in Makana and 258m3/s in Manantali. These average flows have fallen crops, drinking water and sailing), they allow significant hydroelectric considerably between the 1950-1969 and 1970-2011 periods un- power production, but they also limit flood strength and, conse- 80 der the influence of climate deterioration. The annual natural flood quently, their extended areas, sometimes beneficial for ecosystems. usually starts in June and has its strongest flows between August and The guaranteed flow by the dam is around 120 m3/s from January to late September. In Sokotoro, (figure 15) the nearest to the source of July, 180 m3/s in august, 120 m3/s from September to November, and Flow in m3/s the Bafing, the maximum flood is identified in August 1958 with a flow 100 m3/s in December. It should be noted that the optimum sailing 60 of 428  m3/s. The current maximum flood flows seem to be around flow at Bakel would be around 200 to 300 m3/s (OMVS), an impos- 150 m3/s. In Daka-Saidou, these flood flows can reach 2881m3/s (Au- sible flow to provide with the current Manantali facilities. Since 2004, gust 1958) and approach 3000 m3/s in Manantali (2976m3/s in August the flow released by the dam is still below 450 m3/s and completely 40 1906 and 2528m3/s in September 2000). From October, the drying- turbine-based, and no specific flow is released for flood support. In up period returns, but lesser flood peaks can arise up to November. Fouta Djallon, we also note the Téné inputs with an average year-on- From March to May, the flows become very low or non-existent (Fi- year flow around 65 m3/s in Belebe as well as the Kiomo inputs with an Daily mean ow (5 days smoothed) gure 15,16). Since 1987, the Manantali dam has modified the Bafing average year-on-year flow around 13 m3/s in Salouma. 20 Monthly mean ow regimes but also the Senegal river (figure 20) by storing an equiva- lent volume to the average annual flow at the Manantali station, i.e. 8.2km3. Therefore, a significant portion of the Bafing is currently stored 0 01/01 01/07 31/12 Figure 15 > Monthly mean and daily mean river flow on Bafing at Sokotoro / Period 1972 - 2016 FOUTA DJALLON HIGHLAND WATER ATLAS • WATER RESOURCES OF FOUTA DJALLON AND ITS EXTENDED AREA BAOULÉ-BAKOYE, THE RIGHT BANK OF THE SENEGAL IN MALI THE FALÉMÉ The Baoulé joins the Bakoye in Kita, Mali, to the east of the Badinko The Falémé has its source in the Fouta Djallon highland and runs reserve. The Bakoye has its source in Guinea with a relative depen- along the border between Senegal and Mali. Its behaviour is the dency on the Fouta Djallon highland. The Bakoye empties into the same as the Bafing and its average year-on-year flow in Gourbassi Bafing to form the Senegal downstream from the Manantali dam. The is positioned around 93 m3/s, the high-water period appears quite hydrological regime remains natural for these two rivers, and both suddenly in July and extends to October-November with a peak in have seen their hydraulicity fall following the drought in the 1970- September (Figure 17). On average during the high water period, 1990s. In Oualia (Downstream Bakoye), the annual flood generally its flow is between 350 and 450  m3/s on average. The low water starts in July and ends in the first half of September. An overall fall in periods are very marked and the average flows are around 0.1 m3/s flow then follows, despite some flood peaks which can arise in Octo- for the April-May period, the lowest water period. The contrast is ber. Generally, the flow stops or nearly stops in January or February. strong between the 2 periods (2 m3/s on average between January In Oualia, 50 km before its confluence with the Bafing in Bafoulabé, and June against 171 m3/s between July and December). the Bakoye has an average year-on-year flow around 81m3/s. It ac- counts for a little under 25% of the Senegal’s flow. Daily and monthly mean river ow for Ba ng at Makana - 1960 - 2016 period Daily and monthly mean river ow for Faleme at Gourbassi - 1960 - 2012 period 1200 600 Motorized dugout canoe on Senegal river 1000 500 Part de la contribution des affluents du Fleuve Sénégal à la Station de Bakel 800 400 Falémé 22 % Flow in m3/s Flow in m3/s 600 300 400 Bafing 200 49 % Bakoye 19 % 200 Daily mean ow (5 days smoothed) 100 Daily mean ow (5 days smoothed) Monthly mean ow Monthly mean ow Other sources 0 01/01 01/07 31/12 0 10 % 01/01 01/07 31/12 Figure 16 > Monthly mean and daily mean river flow on Figure 17 > Monthly mean and daily mean river flow on Figure 18 > Share contribution of tributaries of Senegal Bafing at Makana / Période 1960 - 2016 Falémé at Gourbassi / Période 1960 - 2012 river at Bakel station 47 Comparison of daily ow before and after Manantali commissioning at Bakel hydrological station - Senegal river HYDROLOGICAL 2500 1996 (After Manantali - dry year) BETWEEN GALOUGO & BAKEL, THE SENEGAL REGIME UNDER INFLUENCE 2000 The Senegal, for this portion, is directly subject to the influence of the Bafing and the Manantali dam (figure 19), despite not modifying the average date that the strongest flows appear. In Baking, flood Flow in m3/s Recent period (2005) 1500 control is significant for the peaks and flood durations are shortened despite improved flood peak generation in comparison to a natural regime. The lack of specific flows increases between 15 and 17% in relation to the natural regime and can even grow for a longer period 1000 (30, 60 or 90 days). The reinforcement of the low water flows by the Manantali dam also leads to a major modification by maintaining Low water replenishment by Manantali flows at 60 m3/s whereas the latter would have been nil or practically nil for over 30 days/year in a natural regime. In a natural regime, the 500 average flow of the Senegal in Bakel is estimated at around 507 m3/s 1972 (Before Manantali ) and, in a “modified” regime for the same period, at 469m3/s. The lack of flow is mainly explained by the loss of evaporation caused by Flow regulation - ood bu ering the extension of the water body at Manantali (16.3 m3/s on average) 0 and by the stored flow (10.8  m3/s on average). We note that the 01/01 01/07 31/12 climate deterioration in the 1970-1990s was felt significantly on the hydraulicity of this portion of the Senegal, reducing from an average Figure 19 > Comparison of daily river flow before and after Manantali commossioning at Bakel station -Senegal river flow of around 916m3/s in Bakel (1950-1969) to nearly half that le- vel, i.e. 413m3/s approximately for the 1970-1987 period to result in Mean annual ows for Senegal river at Bakel hydrological station - 1960 - 2015 period 477m3/s for the 1970-2011 period (figure 20). The recent period 1200 seems to be surplus with an average year-on-year flow of around Starting of West African Manantali dam 632 m3/s (2011-2015). This observation would need to be confir- 1100 droughts commissionning med with future series. 1000 SUMMARY OF THE SENEGAL REGIME IN THE FOUTA DJALLON HIGHLAND’ EXTENDED AREA 900 Module 1960 - 1967 The flows of the regime observed in the period from 01/05/1950 to 800 31/04/2011 show that, on average, the volume flowing in Bakel co- Flow in m3/s 700 Natural module at Bakel between 1903 and 2011 ( From JC Bader ) Module 2012 - 2015 mes from the Bafing for 49%, the Falémé for 22% and the Bakoye for 19%. The remaining 10% comes from intermediary inputs between 600 Module at Bakel between 1960 and 2015 Bakel and the Dibia stations on the Bafing, Kidira on the Falémé and 500 Oualia on the Bakoye (figure 18). Module 1994 - 2011 Module 1968 - 1993 400 300 200 100 0 1960 1961 1962 1963 1964 1965 1966 1967 1968 1969 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 Figure 20 > Yearly mean river flow on Senegal at Bakel / Period 1960 - 2015 FOUTA DJALLON HIGHLAND WATER ATLAS • WATER RESOURCES OF FOUTA DJALLON AND ITS EXTENDED AREA Main river Map 19 owflow > Main river monitoring stations stations on Senegal for Senegal river basin river basin -20.0 -15.0 -10.0 -5.0 20.0 M A U R I T A N I A NOUAKCHOTT PODOR Rosso Dagana DIAMA (Upstream and downstream) Saldé Richard Toll ST LOUIS (quai) Kaédi Sanente Ngoui Gandiol Bango MATAM BAKEL 15.0 Ambidedi DAKAR KIDIRA KAYES S E N E G A L GOUINA Bafoulabé Galougou Kaldé OUALIA M A L I BANJUL GOURBASSY Dibia Toukoto SOUKOUTALI (Manantali) Legend Manding mounts Diangola Senegal from Faleme con uence to the sea MAKANA Sénégal before con uence with Faleme river G U I N E A BAMAKO B I S S A U Faleme basin BISSAU DAKKA SAIDOU Bakoye basin after con uence with Baoule river BOUREYA Topographic highland of Siguirini Balea Kioma à Téliko Baoule basin Balabori Ba ng basin after con uence with Tene river Bélébé G U I N E A Bakoye basin before con uence with Baoule river SOKOTORO Tene basin Soumbakalo Topographic highland of Fouta Djallon Ba ng basin before con uence with Tene river 10.0 MAIN STATION CONAKRY I V O R Y C O A S T Secondary station Projection latitude - longitude WGS 84 - Géohyd - topographic highlands and river basin from L. Ferry, 2017 - Created by Géohyd Anteagroup - Luc Ferry & Axel Aurouet 2017 49 HYDROLOGICAL MAJOR FEATURES OF THE NIGER RIVER HY- TINKISSO, THE DIRECT LINK BETWEEN FOUTA DJALLON AND March and April correspond to the lowest waters with flows below THE NIGER RIVER 5m3/s for March and April. During very dry periods, the average DROLOGICAL REGIMES flow for these months can fall below 2 m3/s. At the Baro station (fi- In Tinkisso, on the upstream part of the Tinkisso river which has In comparison to the Senegal river, Orange describes the Niger re- already covered approximately 150 km, the natural regime corres- gure 22), the behaviour is strongly linked to the behaviour of the gime as a transition tropical regime, notably due to the climate po- ponds to a transition tropical regime with a period of high water Kissidougou station, even though the period with the lowest water sition of the two main tributaries, which are the Niandan and the focused between August and November (figure 21). The Tinkisso already tends to overlap into May. Also in Baro, the flows increase Milo, with their long period of high water and their sources in the slowly rises in May-June then suddenly in July, then in August under suddenly in July-August to reach an average flow of around 780 m3/s Guinean Dorsals. The Tinkisso, also a major tributary, flowing down the influence of the first intense rains, with its average flow between in September. The two months of low waters, March and April, have the Eastern foothills of the Fouta Djallon highland, is described as June and August by nearly 10-fold. Until December-January, it conti- average flows of around 20 to 24 m3/s. During dry years, the flows in being positioned in a pure tropical regime, with lower abundance nues to rise and then dries as quickly as its rise. Since 1974 a hy- these months can approach 2 to 3 m3/s. Finally, the Niandan average due to severe low flows. This feature is largely compensated by more droelectric dam (in reality a simple concrete weir with a fall height of year-on-year flow in Baro rises to nearly 250 m3/s with a specific re- regular inputs from the Niandan and the Milo. The large flood plains 80 m - Olivry 2002) was built on the Tinkisso course. The probable sulting flow of around 20.6l/s/km². During the drought of the 70-80s, in Upper Guinea play a role in controlling floods in the rainy periods. consequences of this work on the hydrological regime are a delay in the average annual flow fell to nearly 38 m3/s (268 m3/s for the 1948- When leaving Guinea, at the level of the Siguiri, the Niger regime the first flows normally expected in June, a flood control effect du- 1964 period to 230 m3/s 1968-1974-1983). This deficit represents remains a transition tropical regime with a sustained low water flow ring the high water period, and the supply of a more or less constant over 1.16km3/year on average at its outlet. At Siguiri, the Niandan and even longer high water periods. The Sankarani, a large tributary flow linked to the hydroelectric power production. To date, the sil- contributes nearly 26% to the Niger flows. which meets with the Niger in Mali, after passing through the Sélin- ting of this dam seems to limit its electricity production capacity to a gué dam, also has a transition tropical regime. Niger then receives few hours per day. From the point of view of hydrological regimes, the Faya, downstream from Bamako. The Kolikoro station plays the even if the latter have certainly been barely modified since 1974, Daily and monthly mean river ow for Tinkisso at Tinkisso - 1955 - 2009 period role of a “rain gauge” for the upstream portion of the Niger until it in Tinkisso the September peak flow displays an average monthly 300 enters the inner delta, a zone over 40,000 km² where it loses a signi- flow around 250 m3/s. Between February and May, the flow is very ficant portion of its volume. It is joined there by the Bani, the source low and stabilises between 7 and 10 m3/s. The average year-on-year of which is in a much less rugged part of the Northern part of Côte flow increases to around 74 to 75 m3/s (1955-1983 period). During 250 d’Ivoire. After passing through the inner delta, the Niger continues the drought period, this average year-on-year flow falls to around its route in a Sahelian regime, crossing Niger, Benin and then retur- 50 to 55 m3/s (1971-1983 period) with years below 35 m3/s (1979). ning to a more tropical regime in the south of Nigeria where it ends In Ouaran, just before its confluence with the Niger, the Tinkisso in the Gulf of Guinea. It is joined along the route by the Bénoué, follows the regime observed upstream and it increased its average 200 where the sources in Chad increase its flow in Nigeria. At the end, year-on-year flow 2.5 times (186 m3/s approximately). The specific the Niger is a “continental river” with a river basin which covers 9 flow (9.9l/s/km²) remains the lowest of the Niger tributaries in this Flow in m3/s countries (Guinea, Mali, Niger, Nigeria, Benin, Chad, Cameroon, Bur- geographical space and its input represents around 18% of Niger 150 kina Faso and Côte d’Ivoire) plus the southern part of Algeria, where inputs at Siguiri before its entry into Mali. the fossil networks of Azaouagh, to the south of Hoggar, could be included in this group. With the uncertainties linked to the defini- THE NIANDAN 100 tion of the river basin and the links with the Taoudéni aquifer, Ferry The Niandan meets the Niger just after the Baro station. Its regime (2012) also suggests including Mauritania and Sierra Leone. In this is still natural for its entire course, even though the Fomi Dam pro- Atlas, only the section of the Niger under significant influence of the ject, planned for many years without any progress, could modify its Fouta Djallon highland and which is the Upper Niger before ente- 50 Daily mean ow (5 days smoothed) regime in the future. Its regime is like a variant of the transition tropi- Monthly mean ow ring the inner delta is discussed (map 20). cal regime. In Kissidougou, on its descent in the Guinean Dorsals, its average year-on-year flow is around 41 to 42m3/s, the water rising period starts from May (11 to 12m3/s approximately) and ends in 0 01/01 01/07 31/12 September at around 113m3/s. The high waters are distributed over 5 months ( July to November). From September, the drying-up pe- Figure 21 > Monthly mean and daily mean river flow on riod starts and ends in January-February. The months of February, Tinkisso at Tinkisso / 1955 - 2009 period FOUTA DJALLON HIGHLAND WATER ATLAS • WATER RESOURCES OF FOUTA DJALLON AND ITS EXTENDED AREA Principales stations Map 20 > Main river de suivi flow stations des débits on upstream de Niger river cours d’eau sur le bassin versant amont du euve Niger basin -12.0 -10.0 -8.0 -6.0 Legend KIRANGO Aval Mandingues mounts Tinkisso sub-basin ER Sub basin of Upstream Niger from its source to its con uence with Sankarani (without a uents ) NIG Mafou sub basin DOUNA Niandan sub basin M A L I Milo sub basin Fié sub basin topographic highland of KOULIKORO Siguirini - Baléa region Sankarani sub basin (without a uents) BAMAKO DIOILA Balé sub basin Dion sub basin Niger sub basin from con uence with Sankarani to Markala Downstream Niger basin (after Markala) KENIEROBA KOUORO 12.0 Bani sub basin before con uence with Niger - Niansira Baoulé sub basin BANANKORO Bagoé sub basin SELINGUE Dialakoro FIFA Ouaran Bani ng sub basin Kouoro PANKOUROU Tiguibery Sirama BOUGOUNI Koudiana - Koura MAIN STATION TINKISSO Secondary station Diélibakoro Noura Souba Dabola Fodékaria KOUROUSSA DEBETE BARO MANDIANA G U I N E A Sormorea Molokoro Sérékoroba KANKAN Balandougou Balan Morissanako Yarakoura BARANAMA FARANAH SANANKORO 10.0 ZIEMOUGOULA KOUTO Sassambaya SAMANTIGUILA Dialoua IRADOUGOU Topographic highland topographic highland of Fouta Djallon of Madinani region Kolédougou Kissidougou KEROUANE Topographic highland of DIAMARADOU Guinean Dorsal Konsankoro I V O R Y C O A S T S I E R R A L E O N E Projection latitude - longitude WGS 84 - Géohyd, DNH Guinée, ABN - topographic highlands and watersehd from L. Ferry, 2017 - Created by Géohyd Anteagroup - Luc Ferry & Axel Aurouet 2017 51 Daily and monthly mean river ow for Niandan at Baro - 1948 - 1983 period Daily and monthly mean river ow for Sankarani at Madiana - 1955 - 2006 period 900 1200 HYDROLOGICAL 800 THE SANKARANI 1000 700 Whilst its source is in Guinea, the Sankarani has a hydrological regime which is slightly different in the sense that the low water periods are greater, and its high water peak seems restricted to 3 months (August 600 800 to October). The ranges between the high waters and low waters are more marked. The rising water period starts in June (65 m3/s in Man- 500 diana – figure 24) and ends in September (910 m3/s in Mandiana). Flow in m3/s Flow in m3/s 600 The drying-up period ends in January and the lowest waters appear 400 in February-April, sometimes May (19 m3/s in Mandian on average). The average year-on-year flow is established around 249m3/s in 300 Mandiana, before leaving Guinea and after its confluence with the 400 Dion. It continues its route until the Sélingué dam, a 2.17 km3 capa- city dam (equivalent to 69 m/s per year). 200 Daily mean ow (5 days smoothed) Daily mean ow (5 days smoothed) 200 Monthly mean ow Monthly mean ow 100 0 0 01/01 01/07 31/12 01/01 01/07 31/12 Figure 22 > Monthly mean and daily mean river flow on Figure 24 > Monthly mean and daily mean river flow on Niandan at Baro / 1948 - 1983 period Sankarani at Mandiana / 1955 - 2006 period Daily and monthly mean river ow for Milo at Kankan - 1940 - 2008 period THE MILO 700 THE NIGER The Milo joins the Niger at Sassando, a little after the Kankan station, In Faranah, it already has an average estimated flow of 60 m3/s and its and has the same behaviour as the Niandan from the point of view 600 hydrological regime is still a variant of the transition tropical regime of the hydrological regime. A transition tropical regime governs this described for the Niandan and the Milo. The rising water period starts river with a rising water period which starts slowly in May (27 m3/s in slowly in May (8.5 m3/s in Faranah) to end in September (165 m3/s in Kankan) (figure 23) to end in September (540 m3/s in Kankan) and a 500 Faranah) and with its flood recession up to February. The lowest wa- drying-up period which ends in January. February, March and April ter period extends from March to April with a minimum in April. It is are the months with the lowest water with average monthly flows measured in Kouroussa, a little before its confluence with the Niandan, measured between 14 and 15m3/s on average for these months. Du- 400 and has an average year-on-year flow around 185 m3/s for the 1954- Flow in m3/s ring the drought years, the flows for these months fell below 1 m3/s 2008 period. Comparison works between the Kouroussa and Baro at Kankan (10 times between 1985 and 1999). The high waters are Stations (on the Niandan) by Orange underline that the flow in Kou- between July and October. The Milo average year-on-year flow in 300 roussa is underestimated by 30%, which would mean an average year- Kankan rises to around 173 m3/s for a specific flow equivalent to the on-year flow more around 265  m3/s. Orange estimates it at around Niandan (20l/s/km²) but the average annual flow has varied signifi- 331 m3/s for the 1950-1980 period. On leaving Guinea, after having cantly between the surplus periods (average annual flow 1940-1979 200 received the Niandan, the Milo and the Tinkisso, the Niger average estimated at 196  m3/s) and the dry periods (average annual flow year-on-year flow reaches 784  m3/s in Banankoro. Further away in 1980-2008 of 140 m3/s). Finally this discrepancy of 56 m3/s on ave- Daily mean ow (5 days smoothed) Mali, at the Koulikoro station, after having received the waters of the rage between these two periods represents a volume of 1.77 km3 100 Monthly mean ow Fié and Sankarani (now regulated by the Sélingué dam), the average at the Milo outlet. The Milo represents around 20% of the Niger’s year-on-year flow reaches 1358  m3/s (Table 5). Ferry’s hydrological inputs at Siguiri. studies (2015) show different hydrological periods through the Kou- 0 likoro station, where the very strong year-on-year variations demons- 01/01 01/07 31/12 trate the effects of major climate cycles (table 5 and Figure 25). From Figure 23 > Monthly mean and daily mean river flow on Milo at Kankan / 1940 - 2008 period FOUTA DJALLON HIGHLAND WATER ATLAS • WATER RESOURCES OF FOUTA DJALLON AND ITS EXTENDED AREA Figure 25 > Hydraulicity Hydraulicity ofbetween of Niger river Niger river between 1907 1907 and 2009 and at 2009 atmonitoring Koulikoro Koulikoro station (from station Luc Ferry) (From Luc Ferry) 0.8 0.6 Hydraulicity index is a balance between annual mean ow and interannual mean ow. A negative value indicate a de cit compa- 0.4 red to normal situation while a positive value indicate an excess compared to the normal situation. A value around 0 characterize a normal situation. 0.2 Hydraulicity index 0 -0.2 -0.4 Mean interannual ow for the period equal to 1 358 m3/s -0.6 1907 1909 1911 1913 1915 1917 1919 1921 1923 1925 1927 1929 1931 1933 1935 1937 1939 1941 1943 1945 1947 1949 1951 1953 1955 1957 1959 1961 1963 1965 1967 1969 1971 1973 1975 1977 1979 1981 1983 1985 1987 1989 1991 1993 1995 1997 1999 2001 2003 2005 2007 2009 1907 to the present day, 1982-1993 stands out as a period with very Table 5 > Hydraulicity periods of Niger river at Koulikoro station between 1907 and 2010 (from Luc Ferry) low hydraulicity (average annual flow of 776m3/s in Koulikoro) and the 1922-1936 and 1948-1969 periods stand out as periods with very AVERAGE ANNUAL MINIMUM MAXIMUM PERIODS YEAR high hydraulicity. The recent period is noted by Ferry as a transition FLOW IN M3/S IN M3/S IN M3/S period. Finally, in Koulikoro, Ferry also demonstrates the influence of REFERENCE PERIOD 1907-2010 1,358 58 5,569 major facilities like the Sélingué dam on the hydrological regime of low waters, notably by raising minimum annual flows since 1982. Finally, it PERIOD WITH LOW HYDRAULICITY 1982-1993 776 84 3,335 leaves Guinea at between 32 and 36m3/s towards the Niger river (Ni- ger, Guinea tributaries and Sankarani) and during flooding episodes, 1907-1921 1,301 36 5,313 nearly 3 days are needed to flow between Kankan and Koulikoro, whereas nearly 3 months are needed in Niger to drain this same Mali 1937-1947 1,245 33 5,333 flood (Ferry 2015). INTERMEDIATE PERIODS 1970-1981 1,228 23 5,200 1994-2010 1,164 96 5,008 Niger river at Niamey 4 periods 1,231 1922-1936 1,794 53 7,088 PERIODS WITH HIGH HYDRAULICITY 1948-1969 1,694 66 6,679 2 periods 1,734 53 350 HYDROLOGICAL 300 250 MAJOR FEATURES OF THE GUINEA COASTAL THE DOWNSTREAM REGIME OF THE KONKOURÉ WHICH IS CONSIDERABLY AFFECTED BY HYDROELECTRIC POWER PRO- RIVER HYDROLOGICAL REGIMES 200 DUCTION SINCE 2000. Flow in m3/s The Guinea coastal rivers are marked by the southern slope of the The Garafiri dam was commissioned in 2000 with significant conse- Fouta Djallon foothills with the most emblematic river being the 150 quences on the low water flow regimes. Ferry et al. (2003) indicate Konkouré (map 22). This southern slope is what the majority of the that in the rainy season, modifications linked to the Garafiri are ba- hydroelectric power facilities rely on, such as the Garafiri and more rely (or not) visible, notably due to year-on-year irregularity, but that recently Kaléta on the Konkouré, Kinkon on the Kokoulo (tributary of 100 the modifications from December to June are visible for the entire the Konkouré) and Banéa, Donkéa and major waterfalls in the Samou network up to the downstream Konkouré (figure 28). However it (tributary of the Konkouré, Badi basin). A modified hydrological re- Daily mean ow (5 days smoothed) seems that the Garafiri dam plays a limited role during the highest gime is now observed on the Konkouré path. The Souapiti project, 50 Monthly mean ow water months (August & September). The Yékémato station, the still on the Konkouré and upstream from the Kaléta, modifies the most downstream on the Konkouré before the estuary, presents regimes a little more in this basin. On the upstream part of the Fatala, increased flows between 25% and 193% between the 1989-1998 there are also small-scale hydroelectric power facilities, notably on 0 01/01 01/07 31/12 and 2000 average for the period between January and June under the Samakou, a tributary of the Fatala around Télimélé. the influence of the Garafiri. For low water, the freshwater inputs Figure 26 > Monthly mean and daily mean river flow on towards the estuary are considerably increased and the flows for the THE NATURAL UPSTREAM OF THE KONKOURÉ BASIN Kakrima at Kaba / 1988 - 2016 period year are considerably smoothed out. The impacts of the Garafiri on The Kakrima course is still natural in its course in the Fouta Djallon. hydrology are summarised thus by Ferry et al. (2013): Before its confluence with the Koukoulo, in Kaba (figure 26), its ave- rage year-on-year flow seems to be located around 82m3/s (1988- Daily and monthly mean river ow for Konkoure at Linsan - 1955 - 2007 period 60 • In the dry season, the flows are much higher than the natural flows 2014 period) Its general regime is similar to a transition tropical re- from Garafiri up to the Konkouré estuary. gime with a period of high waters which extends for 4 months ( July • There is flood control, notably for the Konkouré segment between to October) and a flow peak in August or September estimated the Garafiri dam and the confluence between the Konkouré and 50 around 250 to 270 m3/s on average. The hydrology of the months the Kakrima. of August and September is quite similar. The lowest waters appear in March-April with average flows between 3 and 5 m3/s. The Kou- • For the Konkouré segment between the Garafiri dam and the koulo is very similar to the Kakrima, although slightly influenced by 40 confluence between the Konkouré and the Kakrima: the Kinkon hydroelectric power facilities. Before its confluence with • The complete stop in flows between April 1999 and Sep- the Kakrima in Nianso, its average year-on-year flow is estimated at tember 1999 perhaps had an impact on the aquatic life during Flow in m3/s 67 m3/s (1999-2002: Kakrima estimated at 80.2 m3/s for the same pe- 30 low water (April and May). riod). Its regime is identical to the Kakrima with a high water period in August. The upstream Konkouré at Pont de Linsan (figure 27) is not • The frequent operating stoppages (flow = 0  m3/s) could also modified by the Garafiri dam. It has an average year-on-year flow have consequences on the aquatic ecosystem during the low around 14m3/s for the 1955-2006 sequence and its characteristic 20 water period. regime of a transition tropical regime gives it a high water period • The sudden operating start-ups (from 25 to 100  m3/s) could be extended over 4 months ( July to October). The average flow peak dangerous for those living downstream from the dam. This flushing seems to appear in August (47 m3/s approx.) with a similar charac- 10 Daily mean ow (5 days smoothed) phenomenon probably modifies the low-flow channel of the ter to September (41 m3/s). The overall regime is very similar to the Monthly mean ow Konkouré downstream from the dam (collapsed river banks, sus- Kakrima and Kokoulo with lower water flows in April-May with 1 and pended sediment...). 2 m3/s on average. 0 01/01 01/07 31/12 The recent presence of the Kaléta dam and its impact on the opera- tion of hydrological regimes has not currently been studied in detail. Figure 27 > Monthly mean and daily mean river flow on With 3 times the production capacity of Garafiri, we could assume Konkouré at Linsan / 1955 - 2007 period that the Kaléta facility will also slightly modify the Konkouré flow FOUTA DJALLON HIGHLAND WATER ATLAS • WATER RESOURCES OF FOUTA DJALLON AND ITS EXTENDED AREA Mean mensual flow and daily flow comparison for Konkoure at Telimele before and after the commissioning of Garafiri dam regimes, even if this run-of-river dam should have a lesser or even 1200 negligible influence. The Souapitti project has just been completed, and should largely influence the hydrological regimes of the river basin. 1000 Before 2000 AN INFLUENCE ON THE BADI? The Badi has also small hydroelectric power facilities on the upstream portion. Downstream on the Badi, before its confluence 2000 - 2003 with the Konkouré, the average year-on-year flow for the 1951-58 period reached 193 m3/s, with extremes from 155 to 230 m3/s. For 800 the 1998-2002 period, its average year-on-year flow is measured at Flow in m3/s around 144 m3/s. The maximums are in August (701 m3/s year-on- year 1951-1958 and 524 m3/s for the 1998-2002 period) and the minimums in April (5.5 m3/s year-on-year 1951-1958 and 14 m3/s for 600 the 1998-2002 period). We note here that the facilities on the Badi tributaries respectively date from 1969 (Banéah), 1965 (Donkéa) and 1953 (Grandes Chutes). The matter of the differences obser- ved between the 1951-1958 and 1998-2002 sequences (reduction 400 in flows in August and increase in flows in April) remains open re- garding the reason, even if the trend for increased low water flows suggests that the facilities influence the hydrological regime which is non-negligible for this period of the year. 200 Daily and monthly mean river ow for Kogon at Bridge - 1957 - 2016 period 250 0 January February March April May June July August September October November Décember 200 Figure 28 > Comparison of monthly mean and daily mean river flow of Konkoure at Télimélé before and after commissioning of Garafiri dam 150 THE FATALA AND KOGON Upstream the Salaa falls on kakrima river Flow in m3/s At the Bindan station, downstream from the basin and before its es- tuary outlet, the average year-on-year flow for the 1971-80 period 100 reached 165 m3/s, with extremes from 137 to 193 m3/s. The maximums are in August (542  m3/s year-on-year) and the minimums in April (0.8  m3/s year-on-year). With the reservations linked to low water flows, it should be noted that there was a monthly low water in April 50 1973 lower than 200l/s. The observed daily maximum has reached Daily mean ow (5 days smoothed) 1701 m3/s. The Kogon flow remains difficult to understand with data Monthly mean ow which often seems incorrect. On its upstream portion, the average year-on-year flow seems to establish around 70 m3/s (perhaps a little 0 more). The information available suggests a flow peak in September, 01/01 01/07 31/12 with a similar average in August. On the Kogon, the period of high Figure 29 > Monthly mean and daily mean river flow on waters is focused on these 4 months, generally between August and Kogon at Pont / 1957 - 2016 period November (figure 29), and slightly offset in relation to the most eastern basin of the Konkou. 55 Daily and monthly mean river ow for Gambia at Kéduogou - 1970 - 2014 period 450 HYDROLOGICAL 400 MAJOR FEATURES OF THE GAMBIA RIVER HYDROLOGICAL REGIMES 350 Orange (1990) compares the Gambia river regime to a transition average year-on-year flow (68.3 m3/s approx.) with a minimum an- tropical regime for the section in the Fouta Djallon, therefore compa- nual average flow of 34 m3/s in 1984/1985 (68% deficit compared to 300 ring it to the Niger and Senegal hydrological regime. In its upstream the average year-on-year flow. Two surplus sequences (1918-1940 portion, it is monitored at the Kounsi station in Guinea, then at Ké- and 1951-1971) demonstrated average annual flows around 134 250 Flow in m3/s dougou in Senegal (map 21). The high water period is condensed to 137 m3/s for the period. The hydrological year 1955-1956 is the into 3 to 4 months between August and October with a maximum year recorded with the highest average annual flow (193 m3/s). The in September (290 m3/s at Kédougou 1971-1999 – figure 30). The Koulountou, another tributary of the Gambia which arises in Guinea, 200 rising in the hydrological regime to high waters starts slowly in June. seems to have an average year-on-year flow of 15 to 16 m3/s (estima- Between February and May, the period with the lowest waters, the tion for 4 incomplete years), without certainty, with previous studies 150 flow is very low (< 1.6 m3/s on average for the 1971-1999 period in mentioning an average year-on-year flow around 5m3/s. The hydro- Kédougou). The flows are often nil during April and May. By com- logical regime for this portion of the Gambia should be modified in 100 piling the data from Da Costa & Orange, a timeline of the average the future, notably by the Sambangalou hydroelectric power dam Daily mean ow (5 days smoothed) year-on-year flows from 1903 at Kédougou shows the wide variabi- site, leaving Guinea and upstream from Kédougou, where a planned Monthly mean ow 50 lity of average annual flows (figure 31), in combination with known facility flow of 200 m3/s is being studied. climate trends in West Africa. Since 1903 the average year-on-year flow is established around 107m3/s but the hydrological sequences 0 01/01 01/07 31/12 have largely affected this average annual flow. For the 1972-1994 Figure 30 > Monthly mean and daily mean river flow on period, the average annual flow has fallen by 36% in relation to the Gambia at Kédougou / 1970 - 2014 period of Gambiaof Figure 31 > Hydraulicity Hydraulicity Gambia river between river 1904 between 1999and and1904 1999 at Kédougou at Kédougou monitoring (reconstructed stationfrom (reconstructed from Orange and Da Costa)) Orange and Da Costa) 1 Hydraulicity index is a balance between annual mean ow and interannual mean ow. A negative value indicate a de cit compa- 0.8 red to normal situation while a positive value indicate an excess compared to the normal situation. A value around 0 characterize a 0.6 normal situation. Hydraulicity index 0.4 0.2 0 -0.2 -0.4 -0.6 -0.8 1904 1906 1908 1910 1912 1914 1916 1918 1920 1922 1924 1926 1928 1930 1932 1934 1936 1938 1940 1942 1944 1946 1948 1950 1952 1954 1956 1958 1960 1962 1964 1966 1968 1970 1972 1974 1976 1978 1980 1982 1984 1986 1988 1990 1992 1994 1996 1998 FOUTA DJALLON HIGHLAND WATER ATLAS • WATER RESOURCES OF FOUTA DJALLON AND ITS EXTENDED AREA Principales stations Map 21 > Main river de suivi flow stations desriver on Gambia débits basin de cours d’eau sur le bassin de la Gambie et ses sous-bassins -16.0 -14.0 -12.0 Sandougou S E N E G A L Nianja Bolon Gambia before Nianja Bolon Niériko 14.0 Koussanar Sintiou Malem Dialokoro Maka Goumbeyel M A L I Guenoto BANJUL GOULOUMBOU Fa lé T H E G A M B I A Nieriko au pont routier Wassadou m Fass é Sintian Koundara Aval Missira gounas Niokolokoba Gambia downstream Simenti Upstream Gambia Gambia before Sandangou MAKO KOULOUNTOU AU GUE Sambailo Koulountou KEDOUGOU KOULOUNTOU Guingan ba G U I N E A Gé Koumbanji al B I S S A U KOUNSI ub r a - Co 12.0 ib BISSAU Ndossa Kol Fé Matakou Oundou bac né a Ko m ba - Colib Nianou Téliré ng rim a K o k go B Ka a n n Nun G U I N E A Legend io Té n é ez R MAIN STATION Secondary station Projection latitude - longitude WGS 84 - Géohyd, DNH Guinea- topographic highlands and river basin from L. Ferry, 2017 - Created by Géohyd Anteagroup - Luc Ferry & Axel Aurouet 2017 57 HYDROLOGICAL MAJOR FEATURES OF THE KOLIBA-CORUBAL with an average flow of around 565m3/s for this month (1971-2014). SUMMARY ON HYDROLOGICAL REGIME The hydrological regime in the low water period is also more sus- RIVER HYDROLOGICAL REGIMES tained with an average flow in April-May of 27.5m3/s without ever AT THE OUTLET OF FOUTA DJALLON The hydrological regime of the Kolima (Komba in Fouta Djallon) in approaching a negligible flow. In its lowest recordings for these mon- HIGHLAND its upstream portion remains poorly understood. The origin of these ths, it remains at a flow level of around 13 to 16m3/s. The Senegal, Konkouré and Koliba basins have the largest year-on- sources, not far from the source of the Gambia (map 22), lead us to year average flows from the centre of the Fouta Djallon highland. On link its regime with that of the Gambia. The other major tributary of leaving Guinea, it is the Niger river basin which represents the most the Koliba is the Tominé, with the source to the south having a similar MAJOR FEATURES OF THE SCARCIES RIVER significant water export with a stronger dependency on the Guinean regime to the intermediary between the Konkouré and the Gambia. Dorsals than the Fouta Djallon highland. The southern slopes, which Hydrological data is available for the “Tominé at Gaoual” in the DNH HYDROLOGICAL REGIMES are more rugged, logically have average year-on-year flows with a banks (Figure 30). In view of the variable names between Koliba, The Scarcies are formed by the Kolenté (Great Scarcies) and the greater effect on the outlets. Finally the Gambia basin receives the Tominé or Komba, it remains difficult to say if this station effectively confluence between the Kaba and the Mongo (Little Scarcies). All least water in general with a more reduced river basin influence on represents the Tominé at Gaoual or rather the Koliba after having have their sources in Guinea (southern foothills of the Fouta Djallon the highland in relation to other river basins in the sector (map 24). received the Tominé and the Komba. These data between 1971 for the Kolenté and south-east of Fouta Djallon for the Kaba and and 2014 propose an average year-on-year flow around 180 m3/s the Mongo – map 22). There is few information available on these whereas it has been estimated by Orange (1990) at around 150 m3/s rivers. The Kaba in Guinea, in Koromaya, well before its confluence for the 1979-1987 period. In the Komba basin, before its confluence with the Mongo in Sierra Leone, seems to have an average year- with the Tominé, the average year-on-year flow seems to establish on-year flow around 30 to 35 m3/s (1981-2016 period). Based on around 100 m3/s (BCEOM et al.). The “Tominé at Gaoual” timeline raw information available for this station, it seems that the high wa- emphasises a period of high waters which extends across 4 months ter period lasts around 5 months from July to November included, between August to November included (month with average flow > positioning its regime as a transition tropical regime. The available average year-on-year flow). The flow peak appeared in September data seems to indicate that this period can sometimes be extended Daily and monthly mean river ow for Tomine at Gaoual - 1970 - 2014 period to June during specific years. The water rise starts in May and ends 700 in September, sometimes August, at around 80  m3/s on average (sometimes 30 to 40 m3/s during the 1980s and 202m3/s in 2006). 600 The drying-up period then lasts until February-March. The lowest water months are March and April with an average estimated flow between 3 and 5m3/s. In the 1980s, the average flow for these mon- 500 ths seems to be under 1m3/s. Mahé (1993) suggests an estimated average year-on-year flow for Little Scarcies in Mange (Sierra Leone), after the confluence between the Kaba and the Mongo, of around 400 600 m3/s (rebuilding of the flow between 1951-1989). In the Kolen- té basin (Great Scarcies), the average year-on-year flow in Badera a Flow in m3/s little before the Kolenté forms the border between Guinea and Sier- 300 ra Leone, the average year-on-year flow is estimated at 83m3/s for the 1967-1980 period with a maximum of 102m3/s and a minimum of 37m3/s. The monthly average flow is also reached in September 200 (312m3/s 1967-1980). The lowest flow months are March and April. In the 1970-1980s, the observed flows were systematically below Daily mean ow (5 days smoothed) 100l/s. 100 Monthly mean ow 0 01/01 01/07 31/12 Figure 32 > Monthly mean and daily mean river flow on Tomine at Gaoual / Période 1970 - 2014 “Voile de la mariée” site (bride’s veil) , near Kindia FOUTA DJALLON HIGHLAND WATER ATLAS • WATER RESOURCES OF FOUTA DJALLON AND ITS EXTENDED AREA Principales stations Map 22 > Main river de suivi flow stations des débits on South-west coastal de rivercours basin d’eau sur les bassins de la façade océanique -16.0 -14.0 -12.0 Fé né Géba basin Sopari Lougambé 12.0 BISSAU Bantala Bac Komba Koliba - Corubal basin GAOUAL Komba Tominé Touba KOGON PONT Kakoni Diambata Kellico Kogon basin Karmafassa Kakrima Sangarédi Diawla Pita Koussi Diou Télimélé KAKRIMA - KABA Upstream Konkouré Rio Nunez basin Kondonboufou Nianso Kaba Kora ndi GARAFIRI Kaléta bac Kondoya BINDAN Mamou PONT DE TELIMELE Souapiti Amaria Fatala basin BAC DE BADI PONT DE LINSAN YEKEMATO Yoko KABA A KOROMAYA Tabouna Pont Kolenté Maréla Koumba plantation Kindia Simbaraya 10.0 Konkouré basin Foulaya Daboya BADERA CONAKRY Mongo Yomboyéli Tassin Great Scarcies basin Legend MAIN STATION Little Scarcies basin Secondary station MANGE Main river basin Sub basin FREETOWN Projection latitude - longitude WGS 84 - Géohyd, DNH Guinea- topographic highlands and river basin from L. Ferry, 2017 - Created by Géohyd Anteagroup - Luc Ferry & Axel Aurouet 2017 59 HYDROGEOLOGY AND GEOCHEMISTRY GEOLOGY IN THE HEART OF THE FOUTA DJALLON IS HARDLY CONDUCIVE TO THE PRESENCE OF GENERALIZED GROUNDWATER. GROUNDWATER MAINLY FLOWS ALONG GEOLOGICAL FRACTURES AND IN SURROUNDING FLOOD PLAINS. WELLS AND BOREHOLES THEREFORE HAVE LIMITED PRODUCTIVITY. THAT WATER HAS A LOW MINERAL CONTENT AND TENDS TO BE MORE ACIDIC. A LACK OF GENERALISED GROUNDWATER FROM DISCONTINUOUS OR SEMI-CONTI- and with magnesium or sodium. Mineralisation is low (Conductivity < 300µS/cm) and the waters are acidic (pH of 5 to 6). Far from Fouta IN THE CENTRE OF THE FOUTA DJALLON NUOUS AQUIFER SYSTEMS TO GENERAL Djallon, the terminal proterozoic waters in north Mali have a wide HIGHLAND AQUIFERS IN THE EXTENDED AREA range of quality and mineralisation depending on the surrounding The materials present in the Fouta Djallon highland are, in a raw state The aquifers in the extended area of the Fouta Djallon highland, to rock (sandstone, quartz, dolerites...). Conductivity varies between and not reworked, materials with very poor aquifer capacity. The the east of the Fouta Djallon highland, in the Kankan basin, and on 100 and over 2000µS/cm with an average conductivity around granites and sandstones are hard rocks where water can only cir- the southern fringe of Mali, are fissured aquifers from infra-Cambrian 600 µS/cm. With calcium or sodium carbonate, these waters can culate through fractures, fissures or alternating permeable and im- crystalline formations. The flows are generally weak and groundwater develop towards sodium sulphate facies depending on calcite sa- permeable layers. Dolerites and quartzes are totally impermeable circulation is restricted by the fissure network. We can however find turations. Significantly briny waters (Orange, 1990) hypersulphated rocks. Only schists and greenstone can have aquifer layers but they very productive zones locally on underground circulation networks sodium typical of hydrothermal sources have been noted. The left are only marginally present in the Fouta Djallon highland. The fun- and in the surface alteration zones which generally are thin. The ave- bank water tables of the Falémé correspond to surrounding Birimian damental feature of the Fouta Djallon centre is therefore the lack rage flows for these formations are estimated at between 4.2 and schist where Wackermann and Blot note strong mineralisation. The of a generalised groundwater (Orange, 1990). There is no deep 6.5m3/h. Around Bamako and in an extended area which flows to the sandstone area groundwater (Fouta Djallon) is very diluted and groundwater, the only existing ones are those in the alteration zone, west to Senegal, there are Cambrian sandstone formations encrusted has low mineralisation. The bedrock waters have an intermediary never exceeding 100  m depth, sedimentary covering and recent with schist which are semi-continuous aquifers. These aquifers are between schists and sandstone with dominant bicarbonate-calcium formations (alluviums, elluviums and laterites). These aquifers are dis- more productive than those noted previously but generally remain or sodium. Overall, silica readings are high in groundwaters, except continuous and have a strong vertical difference depending on the unsatisfactory. From Ségou (Mali) to beyond Gao, the formation of the sandstone groundwaters. The granite groundwaters are more stratification of permeable zones, leading to semi-captive or captive Continental Terminal/Quaternary represents the so-called “general” acidic, richer in potassium and chlorine than the basic aquifer waters groundwater (Blot, 1970; Sow, 1984; Traore, 1985). The Fouta Djal- aquifers (Taoudéni basin – map 23) with good permeability linked which have dominant bicarbonate rich in calcium and magnesium. lon is impermeable but has small and very localised groundwater. to its sandy clay substrate with support from the surface water. The The refilling is essentially ensured by infiltration of some rainfall and aquifer formation of Continental Terminal/Secondaire-Tertiaire is water pumping is made up by rivers and sources, and evaporation also present in the eastern and south-eastern part of Senegal (Sene- of lowlands where the groundwater is flush to sub-flush. Despite this, galo-mauritanian basin) and presents interesting potential in terms of wells and boreholes are located locally with general productivity flow which can rise up to 50 m3/h in some sectors. which translates well into the “usability” of different geological sec- tors and confirm the greater productivity of schists and mica schists GEOCHEMISTRY OF THE FOUTA DJALLON (flow often usable above 2.5 m3/h) in comparison to soft sandstone GROUNDWATERS AND ITS EXTENDED AREA and dolerites (flow generally usable between 0.7 and 1.4 m3/h and granite sectors (flow generally usable between 0.7 and 2.5  m3/h). The Birimian area waters, to the North-east of Fouta Djallon and in The growth in drilling depths does not seem to improve producti- the upper Niger basin, are characterised by low concentration of vity of drilling and beyond 50 to 60 m for sandstone, dolerites and dissolved salts (conductivity < 350 µS/cm) with a slight acidity due granites, it even seems to decrease productivity. For schists and mica to the geological substratum. The major ions are represented by schists, greater depths sometimes offer much greater flows. bicarbonates, calcium and magnesium. In the greenstone facies, the waters are much more mineralised (conductivity of 2000 to 3000 µS/ cm). In the Pre-Cambrian sandstone facies, (Madina-Kouta to the north of Fouta) the waters are generally bicarbonated, calciferous Well in a RPID-FDH pilote site FOUTA DJALLON HIGHLAND WATER ATLAS • WATER RESOURCES OF FOUTA DJALLON AND ITS EXTENDED AREA West African Map 23 aquifer > West African systems aquifer systems from M.& From M. Niasse Niasse & C. Mbow C. Mbow © Club © Club du Sahel du Sahel et de et de l’Afrique l’Afrique dede l’Ouest / l’Ouest / OECD OCDE(2006) (2006) -20.0 -10.0 0.0 10.0 20.0 Mourzouk Djado Tin Sérinine Taoudéni - Tanezrouft system Aïr 20.0 NOUAKCHOTT Iullemeden Sénégalo - system Mauritanian DAKAR system Liptako - Chad system Gourma BANJUL NIAMEY BAMAKO BISSAU NDJAMENA OUAGADOUGOU A T 10.0 L CONAKRY ABUJA A FREETOWN N T PORTO-NOVO I YAMOUSSOUKRO MONROVIA Coastal C O LOME system C ACCRA E Coastal sedimentary Topographic highland of A system GUINEA YAOUNDE coastal Guinea N N G UL Topographic highland of F Fouta Djallon Topographic highland of Guinean Dorsal Latitude - longitude projection WGS 84 - Géohyd; CEDEAO, OCDE, mTopographic highlands from Luc Ferry 2017; Created by Géohyd Anteagroup - Luc Ferry & Axel Aurouet 2017 0.0 61 SUMMARY ON WATER RESOURCES The water resources of the Fouta Djallon highland are characterized by the absence of a ge- These hydrological regimes are sometimes disrupted with the influence of large hydraulic neralized aquifer in the heart of the highland. There is little groundwater present and it is very structures which were primarily built for power generation. This is particularly true for the reactive to rainfall, even if scattered hilltop water tables can be found. Significant groundwater Senegal River with the modification of low water regimes downstream from the Manantali resources can be found in water tables associated with waterways amid circulation in the dam on the Bafing in Mali. It is also the case for the Konkouré River, which is entirely Guinean valley floors. This fundamental component of the Fouta Djallon’s hydrosystem exerts consi- and widely developed (Garafiri, Kaléta Souapiti, etc.). derable influence over the hydrological regimes of surface water which all work more or less in the same way: in the highland, flow rates during low water periods (December to June) The way the highland’s hydrosystems function is only partially monitored. There is currently are very low, sometimes close to zero, because they are not supported - or very little - by no monitoring network for groundwater levels in Guinea, even if an inventory of wells and groundwater. With the monsoon’s first rains ( June-July), flow rates increase abruptly to culmi- boreholes is kept up-to-date by the National Department for the Development of Boreholes. nate in September, in parallel with the rainfall. Average flow rates are often multiplied more The National Directorate of Water currently monitors a network measuring flow rates of wa- than fifty-fold between April-May and August-September. The steep slopes over the first terways for all of Guinea, and therefore for the Fouta Djallon highland. However, material kilometers of the waterways then cause spectacular waterfalls (Kionkon, Salaa, etc.). When the and accessibility issues disrupt the correct functioning of this monitoring network. The Fouta rains stop, in the absence of an associated water table, groundwater recession sets in quickly Djallon highland being located at the intersection of three transboundary basin organizations to regain low water levels. The way this hydrosystem works has been characterized by Orange (NBA, OMVS, OMVG) and being the origin of many transboundary rivers, monitoring water (1990) as being a tropical transition regime. In the downstream areas of the Niger and Senegal resources in a sustainable and reliable way is a major issue beyond the borders of Guinea. Rivers, the hydrological regime changes to become a pure tropical regime, then a Sahelian National and international institutions have already considered the creation of an observatory regime characterized by a shortening of the periods of high water. for the Fouta Djallon. In partnership or in synergy with the observatories which exist at the le- vel of basin organizations, this observatory should become an important cornerstone for the In the Sahelian parts of the Niger and Senegal Rivers, in particular, productive aquifers of the sustainability of monitoring networks and for shared knowledge related to water resources in Taoudéni basin and the Senegal-Mauritania basin provide relative support for the flow rates the Fouta Djallon highland. of both rivers. Hydrological regimes are different and the gentle slopes create a very different morphology to the waterways at the heads of the river basins, with much slower flow velocity. FOUTA DJALLON HIGHLAND WATER ATLAS • WATER RESOURCES OF FOUTA DJALLON AND ITS EXTENDED AREA Mean interannual Map 24 > Mean internannualow flow main river on on main river linked rivers form Fouta to Fouta Djallon Djallon highlands and surrounding highland and its extensions Flow de ned from available data and information and for di erent period -15.0 F e r lo -10.0 Sé Bakel 15.0 né ga DAKAR l lé é ou Falém Ba Oualia bie Koulikoro G am Goulombo BANJUL Gourbassi g r a n ge Ni Kou am B Manantali G bi Falém é l ou e ye Gé a ko nt b BAMAKO Ba ou Kedougou - Koliba Koulountou ba Gé l Ga ba Gaoual or u Bag o é m n Daka Saidou g C BISSAU Ba bie r ge Komba Ouaran Ni Bac Kogon To m i n é F O U T A Banankoro D Tinkisso Tinkisso Ko A Kaba a lé go Baou i r im n J A L L O Nu n Fié T Niansan ran ez R io Téné K ak o oul Baro Sanka L Bindan Sokotoro ok K ng A Legend ré Ba Mandiana Télimélé er la N ig ta N ou N ng o Milo Fa River Basin Koromaya K o nk a Kankan K ab nté Ba T lé Mo Badera ké u Niger basin 10.0 n di Mafo ou K ole nd a Konkoure I ur estuary Faranah Bac de Badi Ko C Senegal basin N ia s- CONAKRY cies e G rci r Gambia basin Sca Di o n ca O Interannual U Badala ts tl e Lit I Konkoure basin mean ow ea C E Mange Kissidougou Kerouané N Gr 1358 m3/s A E el Fatala basin (Niger at Koulikoro) Ro k A N Sewafe N Kogon basin FREETOWN D S e wa O Koliba / Corubal basin Jon g R S 500 m3/s A L Great Scarcies basin 250 m3/s Reconstructed o or a Mo Little Scarcies basin ow -M a S a s s a n , d ra n a os Ma Lo l C a v ally u st 30 m3/s Rokel basin Pa Ce t S ain Sewa basin Projection latitude - longitude WGS 84 - Géohyd , DNH Guinea, OMVG, OMVS, ABN - Topographic highlands from L. Ferry, 2017 - Created by Géohyd Anteagroup - Luc Ferry & Axel Aurouet 2017 63 WATER USES IN THE FOUTA DJALLON HIGHLAND FOUTA DJALLON HIGHLAND WATER ATLAS ©IRD / Univ. Montpellier - Adeline Barnaud A GROWING RURAL POPULATION, HIGHLY SIGNIFICANT HYDROELECTRIC POWER AND MINING POTENTIAL This chapter contains the demographic and agricultural elements of the Fouta Djallon highland area, mainly in its Guinean part. It also draws up an inventory of other uses of water such as fishing, hydroelectricity or mining. All of this inventory is compared with the links that these different uses may have with water, whether from a qualitative or quantitative point of view. 65 DEMOGRAPHY AND WATER REQUIREMENTS MAINLY LOCATED IN THE NATURAL REGION OF CENTRAL GUINEA, THE GUINEAN PREFECTURES LINKED TO THE FOUTA DJALLON AMOUNTED TO MORE THAN 3.2 MILLION INHABITANTS IN 2014, AND THEY HAVE SEEN THEIR POPULATION DOUBLE SINCE 1983. THE HEART OF THE HIGHLAND CONTAINS ONE OF THE POOREST POPULATIONS IN GUINEA, AND THE RATE OF ACCESS TO SAFE DRINKING WATER AVERAGES TO CLOSE TO 47% WITHIN THE RPID-FDH PROJECT AREA, WHICH INCLUDES PARTS OF MALI, SENEGAL, GUINEA BISSAU AND SIERRA LEONE. THIS POPULATION IS ESTIMATED TO REPRESENT BETWEEN 15 AND 20 MILLION PEOPLE. ADMINISTRATIVE BOUNDARIES Topographic highlands Map 25 > Topographic and highlands and natural natural region of Guinea of Guinea regions The centre of the Fouta Djallon topographical highland is mainly fo- BAMAKO -15.0 -10.0 cused on Guinea in the natural region of Central Guinea (map 25). Fouta Djallon has 3 administrative regions, which are Labé, Mamou and Faranah, and 10 principal prefectures (Dabola, Dalaba, Dinguiraye, BISSAU 12.0 Kouiba, Labé, Lélouma, Mali, Mamou, Pita and Tougué) (map 26). In CENTRAL GUINEA its RPID definition, the central zone of the Fouta Djallon highland (or the restricted extended area) directly covers 15 prefectures, with an extra 7 which are partially covered (map 26). These 15 prefectures UPPER GUINEA cover the Labé, Mamou, Faranah, Boké and Kindia regions. The 7 other C O A S TA L prefectures contain part of the Kankan administrative region. Finally, in GUINEA this definition established as part of RPID, it would be possible to also 10.0 add the prefecture of Kouroussa which itself could have a link with the borders of the Fouta Djallon topographical highland. It should be Legend CONAKRY noted that the FAO definition of the Fouta Djallon highland includes 6 Topographic highland of Fouta Djallon additional prefectures in Guinea, covering nearly all of Guinea. Coastal Guinea highland In total, 65% of Guinea’s prefectures are linked to the RPID restric- Topographic highland of Guinean Dorsal FOREST GUINEA ted extended area of the Fouta Djallon highland (22 prefectures out Topographic highland of Siguirini-Baléa region FREETOWN of 34). The RPID wider extended area of the Fouta Djallon highland Topographic highland of manding mounts (map 2) directly covers 5 countries (Guinea, Sierra Leone, Guinea Bis- Banié-Niandan Chain 8.0 sau, Mali and Senegal) and the area of influence covers 8 countries Topographic highland of Madinani region (adding Sierra Leone, Mauritania, Niger and The Gambia). By inclu- Projection latitude - longitude WGS 84 - Géohyd - topographic highland from L. Ferry, 2017 - Created by Géohyd Anteagroup - Luc Ferry & Axel Aurouet 2017 ding the 22 Gambia prefectures already mentioned above, there are nearly 61 prefectures (or districts in Sierra Leone) which are covered by the RPID wider extended zone of the Fouta Djallon highland, i.e. 17 administrative regions. In total, the Fouta Djallon highland RPID area of influence covers 71 administrative regions (or districts for Sierra Leone) in 8 countries. Finally we note that the Fouta Djallon highland is linked to 3 transboun- dary basin organisations (the Niger basin authority, the Senegal river development authority and the Gambia river development authority) which, whilst they do not have administrative status, are the manage- ment and planning bodies for the water resources where the projects directly benefit from the administrative bodies focused on the Fouta Djallon highland. Panel referring to the Fouta Djallon near Dalaba FOUTA DJALLON HIGHLAND WATER ATLAS • WATER USES IN THE FOUTA DJALLON HIGHLAND Guinean natual Map 26 > Natural regions region and of Guinea prefectures and associated associated RPID-FDH to prefectures of RPID Fouta Djallon highland Guinea Kolda Velingara Koulikoro Sedhiou Tambacounda -14.0 -12.0 -10.0 BAMAKO-8.0 Pirada Kedougou Commune 6 Farim Contuboel S E N E G A L Kita Sonaco Pitche KOUNDARA Kenieba M A L I Kati G U I N E A B I S S A U Gabu MALI 12.0 Kangaba Boe GAOUAL Tite Xitole KOUBIA Buba Empada Quebo SIGUIRI LELOUMA LABE TOUGUE DINGUIRAYE Bedanda Bougouni Komo Cacine BOKE PITA Yanfolila TELIMELE DALABA KOUROUSSA MANDIANA DABOLA FRIA KANKAN MAMOU BOFFA KINDIA FARANAH DUBREKA 10.0 COYAH CONAKRY FORECARIAH Koinadugu Bombali Kambia KISSIDOUGOU KEROUANE Legend Port Loko Tonkolili Kono BEYLA Administrativ boundaries level 2 (Prefecture in Guinea) GUECKEDOU Natural regions FREETOWN S I E R R A L E O N E MACENTA Coastal Guinea Western Area Central Guinea Upper Guinea Moyamba Kailahun Bo 8.0 Forest Guinea Kenema NZEREKORE LOLA Guinean prefectures and RPID Prefecture fully integrated to RPID FDH YOMOU Bonthe Prefecture partially integrated to RPID FDH L I B E R I A Pujehun Prefecture out of RPID FDH Projection latitude - longitude WGS 84 - Géohyd - National Institute of Statistics of Guinea (2014)- Created by Géohyd Anteagroup - Axel Aurouet 2017 67 DEMOGRAPHY POPULATION IN THE HEART OF THE FOUTA DJALLON HIGHLAND AND ITS EXTENDED AREAS POPULATION IN THE HEART OF THE HIGHLANDS sub-region tend towards 100 litres per inhabitant and per day. If this RPID is currently estimated at nearly 69,500,000 inhabitants with rate was reached, the necessary volume of water for the population populations mainly located on the oceanic front in Dakar, Conakry The population living in the RPID zone at the heart of the Fouta would nearly reach 209 Mm3, including 118 Mm3 for the 15 prefec- and Sierra Leone, but also around Bamako, Niamey, Tilabéry and Djallon highland is nearly 3,250,000 people (15 prefectures fully tures for the RPID zone at the heart of the Fouta Djallon highland. In Dosso. As a comparison, we note that the population of the Niger included in the Fouta Djallon highland - 2014 census). This figure the last 30 years, the population of the Fouta Djallon highland has basin is estimated at over 135 million inhabitants, the Senegal ba- reaches nearly 5,715,000 people for 2014 by including 7 additional more than doubled, increasing from 1,800,000 inhabitants in 1983 sin at 10.6 million inhabitants and the Gambia basin at a little over prefectures which are partially within Guinea. In total, nearly 53% approximately to around 3,250,000 inhabitants currently (figure 34). 5 million. Most of the population in these extended areas cover of Guinea’s total population (nearly 10 million inhabitants in 2014) This demographic growth in the heart of the Fouta Djallon highland Guinea itself, where over 5,715,000 inhabitants are covered. Mali is more or less linked to the Fouta Djallon highland (figure 33). The has notably caused increased pressure on water resources, wood has the maximum 6,225,000 inhabitants affected. This population is population density at the heart of the highland is also one of the and land resources. slightly overestimated as it includes regions partially included in the highest in Guinea (between 50 and 100 inhab./km²) with maximum NEARLY 15 MILLION INHABITANTS IN THE EXTENDED AREAS extended areas (Kayes and Koulikoro). Finally Senegal has around density in the prefecture of Labé, where the density approaches OF FOUTA DJALLON 830,000 inhabitants. Guinea and Mali therefore have nearly 68% of 150 inhab./km²(map 27). As throughout Guinea, except Conakry the population in the extended areas, 12% for Mali, a little over 7% and some surrounding areas, the population is mainly rural (nearly The population of the different extended areas of the Fouta Djallon for Sierra Leone and less than 3% for Guinea-Bissau. Still based on a 70%). Lélouma, Pita and Télimélé are the prefectures in Fouta Djal- highland has not been assessed accurately. By including populations ratio of 30 litres per inhabitant per day, the annual water demand for lon with the most rural populations. Fria and Kindia have the most at an administrative region level, it can be estimated at 15,000,000 the populations in these zones represents a volume between 165 “urban” population. Based on an average current ratio of 30 litres inhabitants maximum. This population rises a little to over 22,000,000 and 240 Mm3, i.e. between 5.2 and 7.6m3/s flow equivalent. If the per inhabitant and per day, the annual water demand of popula- inhabitants by including the adjacent regions very partially linked to objective of 100 litres per inhabitant per day is reached, between tions in the heart of the highland is a volume of 62.5 Mm3, i.e. nearly the Fouta Djallon RPID extended area (map 29). The entire popula- 550 and 800 Mm3 of water will be required to supply the popula- 2 m3/s flow equivalent. The objectives to satisfy water needs in the tion of the 8 countries which are part of the Fouta Djallon highland’ tions in these zones. Population Figure 33 > of Population of Guinea that is concerned by Guinea concerned Figure 34 > Population trend between 1983 and 2014 in Population trend between 1983 and 2014 in Guinea Fouta Djallon in 2014 by Fouta Djallon in 2014 Guinea and in prefecture of Fouta Djallon and in Fouta Djallon highland guinean prefectures Entire Guinea 12 M 31 % concerned by Fouta Djallon 10,5 M inhab 10 M (15 Prefectures) Number of inhabitants in Million 23 % partially 8M concerned by Fouta Djallon 7.1 M inhab (7 Prefectures) 6M 15 Prefectures of Fouta Djallon 4,6 M inhab 4M 3.2 M inhab 46 % unconcerned by Fouta Djallon 2.5 M inhab (other guinean prefectures) 1,8 M inhab 2M 0 1983 1996 2014 House in the Fouta Djallon highland FOUTA DJALLON HIGHLAND WATER ATLAS • WATER USES IN THE FOUTA DJALLON HIGHLAND Population and and Carte 27 > Population population density population density in inside Fouta guinean Djallon prefectures ofguinean prefectures highland (2014)(2014) Fouta Djallon -15.0 KOLDA -14.0 -13.0 -12.0 -11.0 -10.0 -9.0 S E N E G A L Prefectures fully associated Prefectures partially associated to RPID Fouta Djallon highland to RPID Fouta Djallon highland KOUNDARA M A L I U NOVA LAMEGO S A K o li k oye MALI Gam ba BAFATA I S bie 12.0 Ba B N E A GAOUAL I U KOUBIA G n LELOUMA TOUGUE Tinkisso ng go Ko ima LABE SIGUIRI kr Ba DINGUIRAYE Ka r o Téné ge ul ko PITA Ko Ni 11.0 BOKE TELIMELE DABOLA DALABA KOUROUSSA our é MANDIANA nk FRIA Ko MAMOU KANKAN N iandan Legend BOFFA a Ko Kab lo Population density lent Mi KINDIA FARANAH < 20 hab / km² 10.0 é u 20 - 30 hab / km² DUBREKA Mafo 30 - 40 hab / km² COYAH 40 - 50 hab / km² 50 - 100 hab / km² KABALA FORECARIAH KAMAKWIE 100 - 500 hab /km² > 500 hab / km² CONAKRY KISSIDOUGOU KEROUANE L E O Population KAMBIA R R A N I E 1 670 000 hab S 9.0 MAKENI E 700 000 hab PORT LOKO BEYLA MACENTA -13.0 GUECKEDOU 100 000 hab NZEREKORE Projection latitude - longitude WGS 84 - Géohyd - National Institute of Statistics of Guinea (2014)- Created by Géohyd Anteagroup - Axel Aurouet 2017 69 Mean and rate for access water in administrative regions of Labe and Mamou DEMOGRAPHY in house 1% Tap pubic 1% Neighbour 3% ACCESS TO DRINKING WATER SANITATION The drinking water access rate is defined by access to water from a In 2002, the toilet access rate was under 48% in the Labé region and tap (public, personal or neighbouring) via a borehole, an equipped nearly 60% in the Mamou region (figure 36). Various types of latrines 23% source or an “improved” well. The drinking water access rate in the (covered or uncovered, ventilated or improved) are the main method Fouta Djallon Highland was established at around 47% in 2002 (figure of accessing toilet facilities. The most recent studies completed by the River / Lake/ pond 35). This rate is slightly below the average in Guinea (77% in 2015 – OMVS (2009) mention that nearly 70% of households surveyed in the map 28) but has increased in relation to the 1994 figures. The region Guinea zone of the Senegal basin had a latrine, which is higher than the Borehole of Labé has an access rate (51.6%) slightly above the Mamou region 2002 survey. These percentages are lower than those identified in the 31% (43.2%) which is also the region which had the lowest access rate in Mali zone of the Senegal river basin where a latrine rate of over 98% the country in 2002. The main method of drinking water supply is a was observed in OMVS studies. Finally, the washing facilities rate in the borehole and a standard well in the Labé region. In Mamou, a supply regions of Mamou and Labé seems to be around 83% and on average from rivers/lakes/seas and river were most common in 2002, followed the villages in these regions have 2.6 community or shared latrines. Ordinary well by a borehole. Urban populations have a higher access rate than rural Still according to the survey carried out by the OMVS, the average 21% populations (74.7% vs. 52.8% in Guinea). For the Fouta Djallon RPID number of rainwater collection networks is 0 in the Mamou and Labé 9% 7% extended area, it should be noted that the drinking water access rate regions, with an average rate in the Senegal basin which is not much Natural advanced seems lower in Guinea in relation to the Mali zone of the Senegal higher. In 2002, the administrative region with the highest levels of po- sources well 4% eqquiped basin, particularly with regards to an increased percentage of water verty in Guinea was Labé (65% of individuals below the poverty line). sources supply through hydrants in the Mali zone. In its socio-economical stu- In Mamou, this rate was below 45%. In addition to being one of the dy of the Senegal river basin, the OMVS also mentions that most of poorest regions in Guinea, Labé was also the region with the broadest villages in Guinea (90% of Guinea villages in the Senegal river basin) level of poverty in Guinea. Figure 35 > Modality and rate of access to drinking water have seasonal difficulties in accessing drinking water, explaining the hi- in the administrative regions of Mamou and Labé (2002) gher rate of using rivers and backwaters to collect drinking water. Para- doxically, only 25% of villages surveyed in the Mali zone have seasonal difficulties. This fragility in accessing drinking water in the Fouta Djallon Figure 36 > Access to the toilet in the administrative regions highland reflects the low availability of underground waters and their of Mamou drying up, which goes hand in hand with the rainy season. Acc ess to and for(2002) Labé toilet Labe and Mamou administrative region in 2002 Other 6% de laof Map 28 > Percentage Pourcentage the population population with access ayant accès improved to à water source des sources d’eau at potable national scale (2015) améliorées à l’échelle nationale (2015) -25.0 -20.0 -15.0 -10.0 -5.0 0.0 5.0 10.0 Mauritania Cabo Verde Niger 15.0 Legend Senegal None % of national population - 2015 The Gambia Mali 46 % 58 à 60 % 60 à 70 % Burkina Faso Latrins Guinea-Bissau 70 à 80 % Guinea 48% 80 à 90 % Benin 10.0 > 90 % Access to an improved water source refers to the percentage Sierra Togo Nigeria of the population using an improved drinking water source. The Leone improved drinking water source includes piped water on premises Ghana (piped household water connection located inside the user’s Ivory Coast dwelling, plot or yard), and other improved drinking water sources (public taps or standpipes, tube wells or boreholes, protected dug wells, Liberia protected springs, and rainwater collection). Cameroon 5.0 Projection lat/long WGS 84 - Source : WHO/UNICEF Joint Monitoring Programme ( JMP ) for Water Supply and Sanitation . Created by Géohyd Anteagroup - Axel Aurouet 2017 Flush 0.35 % FOUTA DJALLON HIGHLAND WATER ATLAS • WATER USES IN THE FOUTA DJALLON HIGHLAND Bucket 0.1% Population andand Map 29 > Population population density population density of administrative in administrative zonesof regions regions of extension Fouta of Fouta Djallon Djallon highland highland (2014) extension zones 20.0 -20.0 -15.0 -10.0 -5.0 NOUAKCHOTT 15.0 DAKAR A T L BANJUL A BAMAKO N T BISSAU I C Legend O Population density C E 10.0 < 20 inhab / km² A CONAKRY 20 - 30 inhab / km² N 30 - 40 inhab / km² Population in number of inhabitant 40 - 50 inhab / km² FREETOWN 50 - 100 inhab / km² 3 200 000 inhab 100 - 500 inhab /km² 1 000 000 inhab YAMOUSSOUKRO > 500 inhab / km² 200 000 inhab Projection latitude - longitude WGS 84 - Géohyd , Census from Guinea, Mali, Senegal, Guinea Bissau, Sierra Leone, Gambia, Mauritania , OMVS, NBA, OMVG- Topographic highland from L. Ferry, 2017 - Creatd by Géohyd Anteagroup - Axel Aurouet 2017 71 AGRICULTURE FONIO IS THE EMBLEMATIC CROP OF THE FOUTA DJALLON HIGHLAND. CASSAVA AND MAIZE REMAIN PREDOMINANT. THE FOUTA DJALLON IS ALSO A SIGNIFICANT CATTLE FARMING AREA TO THE SOUTH, AND CONTINENTAL FISHING PLAYS AN IMPORTANT ROLE. TAPADE, WHICH IS THE FOUTA Breakdown of agricultural production in tons by type In the administrative regions DJALLON’S TYPICAL AGRARIAN SYSTEM, IS AN INGENIOUS SYSTEM RECOGNIZED BY THE FAO. of Labé and Mamou in 2000 - 2001 100% Potatoes 10 000 T - 1,1 % THE TAPADES, AN ORIGINAL CULTIVATION SYSTEM IN THE HEART OF FOUTA DJALLON HIGHLAND Taro 100 000 T - 11,4 % Guinea has good agro-climatic conditions, a large hydrographic cultivation (12% of crops) and, to a lesser extent, irrigated and bank network and a polder which encourages the practice of agricultural cultivation (4% of crops for each type in the Mamou region and less 90% activities during a good part of the year. Agriculture is the main pro- than 1% in the Labé region). The irrigation water requirements are duction activity in Guinea, involving around 85% of the population. estimated at nearly 21Mm3/year for the Mamou and Labé regions In the Fouta Djallon highland zone, the cultivation system is traditional (2007-2008 SDAGE Senegal). 80% Sweet potatoes 140 000 T - 15,9 % and based on slash-and-burn deforestation with a specific feature in AGRICULTURAL PRODUCTION IN THE HEART OF THE Fouta Djallon which is the tapades (an agricultural method unique to HIGHLAND Fouta Djallon). These are enclosures forming patches of greenery and habitats on the Fouta Djallon plateaus. These are enclosed residence, In all prefectures associated to RPID -FDH like region in the heart of 70% domestic livestock farming and gardening areas. They allow livestock Fouta Djallon highland (Labé – Mamou), the most significant pro- farming as well as cereal crops (fonio) on open field spaces around duction is cassava (770,000 tonnes/year) (figure 37 – map 30). It is the tapades, as well as having protected gardens. These gardens pro- important to note that this geographic sector is the principal produ- cer of fonio (361,000 tonnes i.e. 74% of production in Guinea – map 60% duce all year round, thanks to continued support of organic, grass and ash material. The Guinea tapades were often presented as the solu- 39), maize (440,000 tonnes, i.e. 59% of production in Guinea- map Cassava 258 000 T - 29,4 % tion to the problem of coexistence between agriculture and livestock 32) and potatoes (53,000 tonnes i.e. 100% of the production in Gui- farming. This traditional farming method was listed in the “Globally nea). By including the 7 partially covered prefectures, we can also 50% Important Ingenious Agricultural Heritage Systems” (GIHAS) by the include cassava (960,000 tonnes i.e 59% of production in Guinea) FAO. and peanut (409,000 tonnes i.e 76% of production in Guinea). In to- tal between 55 and 66% of the Guinea cereal production is linked to CULTIVATION IN THE HEART OF FOUTA DJALLON HIGHLAND 22 prefectures in the Fouta Djallon highland RPID area, which makes 40% Arachide 36 500 T - 4,2 % At the centre of the Fouta Djallon, the cultivated surface area was the region a “granary” for Guinea. estimated at nearly 260,000 ha in 2001 for the regions of Labé and Mamou. This surface area reaches 420,000 ha by including the Aerial view of “tapades”, near Labé Maize 121 000 T - 13,8 % 30% Boké region. The cultivated surface areas in the regions of Labé and Mamou represent 19% of the cultivated surface areas in Guinea. In the region of Labé, fonio is the main crop (28% of cultivated surface Mil 16 000 T - 1,8 % areas), followed by maize (20%), potatoes (13.5%) and cassava 20% Sorgho 6 900 T - 0,8 % (11%). Next is peanut and taro (6 to 7% each). The region of Mamou also has significant surface areas of fonio crops (21%) but rice crops Fonio 113 500 T - 12,9 % are the most common (25%) in terms of surface area. Unlike the Labé region, there are few potato crops and more millet. In the 10% Boké region, the most common crop is rice (map 31), which covers nearly 48% of the cultivated surface area in the region. Rain-fed Rice 76 000 T - 8,7 % cultivation is largely dominant in the Labé region (80% of crops) and 0% Mamou region (98%). In the region of Labé, there are also low-land Data coming from national agricultural census of Guinea 2000 / 2001 Figure 37 > Distribution of agricultural production in tons and by type of crop in administrative region of Labe and Mamou in 2000 - 2001 FOUTA DJALLON HIGHLAND WATER ATLAS • WATER USES IN THE FOUTA DJALLON HIGHLAND Production and Map 30 > Production share and share of production of production of manioc of cassava in Guinean inside Guinean prefecture prefectures of of Fouta Djallon (2016) Fouta Djallon Highland -15.0 -14.0 KITA MEDINA GONASSE -13.0 -12.0 -11.0 -10.0 -9.0 13.0 KOLDA SEDHIOU S E N E G A L Prefectures associated to Prefectures partially associated to RPID Fouta Djallon RPID Fouta Djallon M A L I U NOVA LAMEGO KOUNDARA S A KANGARA BAFATA MALI I S BISSAU 12.0 B BOLAMA N E A GAOUAL KOUBIA I U TOUGUE SIGUIRI G LELOUMA LABE DINGUIRAYE BOKE PITA 11.0 TELIMELE DALABA MANDIANA KOUROUSSA DABOLA FRIA MAMOU KANKAN BOFFA Legend KINDIA FARANAH DUBREKA Share of production 10.0 in total production of the prefecture (%) COYAH KABALA < 15 % CONAKRY KAMAKWIE KEROUANE 15 à 20 % FORECARIAH KISSIDOUGOU 20 à 30 % L E O 30 à 35 % R R A N 35 à 40 % KAMBIA I E S 9.0 E 40 à 46 % MAKENI Production in Tons PORT LOKO BEYLA 180 000 tonnes GUECKEDOU MACENTA 80 000 tonnes FREETOWN 20 000 tonnes KAILAHUN 2 700 tonnes Projection latitude - longitude WGS 84 - Géohyd - Ministry of agriculture of Guinea (census 2016) - Created by Géohyd Anteagroup - Axel Aurouet 2017 73 Production andand Map 31 > Production share share of production of production of riceof rice inside in Guinean Guinean prefecture prefectures of of Fouta Djallon Fouta Djallon (2016) Highland -15.0 -14.0 MEDINA GONASSE -13.0 -12.0 -11.0 -10.0 KITA -9.0 13.0 KOLDA SEDHIOU S E N E G A L Prefectures associated to Prefectures partially associated to RPID Fouta Djallon RPID Fouta Djallon M A L I U NOVA LAMEGO KOUNDARA S A BAFATA MALI KANGARA I S BISSAU 12.0 B E A KOUBIA BOLAMA GAOUAL I N TOUGUE U SIGUIRI G LELOUMA LABE DINGUIRAYE BOKE PITA 11.0 TELIMELE DALABA KOUROUSSA MANDIANA DABOLA FRIA MAMOU KANKAN BOFFA Légende KINDIA FARANAH DUBREKA Share of production 10.0 in total production of the prefecture (%) COYAH KABALA < 15 % CONAKRY KAMAKWIE KEROUANE 15 à 25 % FORECARIAH KISSIDOUGOU 25 à 45 % L E O 45 à 55 % R R A N 55 à 60 % KAMBIA I E S 9.0 E 60 à 70 % MAKENI PORT LOKO Production in Ton BEYLA 175 000 tons GUECKEDOU MACENTA 80 000 tons FREETOWN 25 000 tons KAILAHUN Projection latitude - longitude WGS 84 - Géohyd - Ministry of agriculture of Guinea (census 2016) - Created by Géohyd Anteagroup - Axel Aurouet 2017 FOUTA DJALLON HIGHLAND WATER ATLAS • WATER USES IN THE FOUTA DJALLON HIGHLAND Production andand Map 32 > Production share share of production of production ofinside of maize maize in Guinean Guinean prefecturesprefecture of Fouta Djallonof Fouta Djallon (2016) Highland -15.0 -14.0 -13.0 -12.0 -11.0 -10.0 KITA -9.0 MEDINA GONASSE 13.0 KOLDA SEDHIOU S E N E G A L Prefectures associated to Prefectures partially associated to RPID Fouta Djallon RPID Fouta Djallon M A L I U NOVA LAMEGO KOUNDARA S A BAFATA KANGARA MALI I S 12.0 BISSAU B BOLAMA E A GAOUAL KOUBIA I N U TOUGUE SIGUIRI G LELOUMA LABE DINGUIRAYE BOKE PITA 11.0 TELIMELE DALABA MANDIANA KOUROUSSA DABOLA FRIA MAMOU KANKAN BOFFA Legend KINDIA FARANAH DUBREKA Share of production 10.0 in total production of the prefecture (%) COYAH KABALA <5% CONAKRY KAMAKWIE KEROUANE 15 à 7,5 % FORECARIAH KISSIDOUGOU 7,5 à 10 % L E O 10 à 15 % R R A N 15 à 20 % KAMBIA I E S 9.0 E 20 à 36 % MAKENI Production in Tons PORT LOKO BEYLA 80 000 tons GUECKEDOU MACENTA 30 000 tons FREETOWN 10 000 tons 2 200 tons KAILAHUN Projection latitude - longitude WGS 84 - Géohyd - Ministry of agriculture of Guinea (census 2016) - Created by Géohyd Anteagroup - Axel Aurouet 2017 75 AGRICULTURE Number of cattle, sheep, goat and pig for Guinea prefecture of Fouta Djallon (2016) LIVESTOCK FARMING IN THE HEART OF FOUTA DJALLON 14 000 000.00 Legend HIGHLAND Cattle Whilst the Fouta Djallon Highland central area can be considered as 12 000 000.00 Sheep the granary of Guinea, it is also the main area for livestock farming Goat in Guinea (map 33). Livestock farming is extensive and traditional. Pig Between 55 and 60% of Cows, Sheep and Goats in Guinea are 10 000 000.00 found in the 15 prefectures associated with the Fouta Djallon (figure Nomber of head 38). This figure rises to over 80% when including the seven partial- 8 000 000.00 ly covered prefectures. The number of Cows is nearly 4,200,000 (2016) with around 1,430,000 Sheep and 1,900,000 goats. Based on a water requirement of 30l/TLU and per day (TLU = Tropical Li- 6 000 000.00 vestock Units), nearly 31 Mm3/year is required for watering in the 15 prefectures. This volume rises to nearly 45Mm3/year when including 4 000 000.00 the 7 additional prefectures. Finally, we note that there is also poultry farming with approximately 1 in 3 households having them. The cow and goat population continues to grow in the highland but is less 2 000 000.00 sustained than in other Guinea regions. AGRICULTURE IN THE EXTENDED AREA OF - 15 Prefectures associated to RPID 22 Prefectures associated or FOUTA DJALLON HIGHLAND Fouta Djallon highland partially associated to RPID Total for Guinea Fouta Djallon highland (15 + 7) CULTIVATION Ministry of agriculture of Guinea (census 2016) Figure 38 > Number of cattle, sheep, goats and pigs in the Guinean prefectures of the Fouta Djallon highland (2016) In the extended area of the Fouta Djallon Highland’s RPID, West Guinea and the Northern fringe of Mali and Senegal mainly contain LIVESTOCK FARMING AND PASTORALISM Maize, Rice, Millet and Sorghum crops. Finally, there is some cotton production, particularly in South-East Mali. The Mali sector also has The Malian herd is one of the largest in the region with extensive the largest surface area of Sorghum and Millet. The main cultivation livestock farming. Cows are the most common (zebus) followed by type remains rain-fed (over 90% of surface areas) notably in Mali and sheep and goats. In the fringes of Senegal, the region of Kanel and Guinea. To a lesser extent there is low-land cultivation, bank cultiva- Matam, outside of the Fouta Djallon highland extended area RPID, is tion, flood recession cultivation and irrigated cultivation. In Senegal, the ultimate livestock farming region. In the extended area, there are flood recession cultivation is more common, as well as in the Malian 5 major pastoral systems like those in Mali: the nomad or transhu- part corresponding to the Niger river inner delta. Irrigated cultiva- mant pastoral system (Sahelian zone) the transhumant agro-pastoral tion is also more common in Senegal, but continues to grow across system linked to flooded land (inner delta), the transhumant or se- the zone. Finally, there is also market gardening production, mainly dentary agro-pastoral systems linked to exposed land (systems main- with peanuts, then onion, okra, pepper, bananas, potatoes, and lo- ly in the RPID extended area, agro-pastoral systems in cotton areas cally tomatoes. (South-East Mali) and suburban livestock farming systems (often with modern equipment). Plowing in Fouta Djallon highland FOUTA DJALLON HIGHLAND WATER ATLAS • WATER USES IN THE FOUTA DJALLON HIGHLAND Cattle and Map 33 > cattle Cattle density and Cattle in Guinean density inside prefectures Guinean prefectures of of Fouta Fouta Djallon Djallon Highland (2016) (2016) -15.0 -14.0 MEDINA GONASSE -13.0 -12.0 -11.0 -10.0 KITA -9.0 13.0 KOLDA SEDHIOU S E N E G A L Prefectures associated to Prefectures partially associated to RPID Fouta Djallon highland RPID Fouta Djallon highland M A L I U NOVA LAMEGO KOUNDARA S A KANGARA BAFATA MALI I S BISSAU 12.0 B E A KOUBIA BOLAMA GAOUAL I N TOUGUE U SIGUIRI G LELOUMA LABE DINGUIRAYE BOKE PITA 11.0 TELIMELE DALABA KOUROUSSA MANDIANA DABOLA FRIA MAMOU KANKAN BOFFA KINDIA FARANAH Legend DUBREKA 10.0 Cattle density < 15 unit / km² 15 - 20 unit / km² COYAH KABALA CONAKRY KAMAKWIE KEROUANE 20 - 30 unit / km² FORECARIAH KISSIDOUGOU 30 - 40 unit / km² L E O 40 - 50 unit / km² R R A N 50 - 100 unit / km² KAMBIA I E S E 9.0 Number of cattle MAKENI PORT LOKO 600 000 cattles BEYLA GUECKEDOU MACENTA 300 000 cattles 100 000 cattles FREETOWN 20 000 cattles KAILAHUN Projection latitude - longitude WGS 84 - Géohyd - Ministry of agriculture of Guinea (census 2016) - Created by Géohyd Anteagroup - Axel Aurouet 2017 77 Contributions of guinean prefectures in the AGRICULTURE overall uses of pesticides in Guinea Guinean prefecture outside RPID Fouta Djallon highland CONTINENTAL FISHING ACTIVITY FUTURE THREATS TO WATER QUALITY? Whilst deemed to be a relatively marginal activity due to the Fouta Agriculture in a broad sense is a fundamental component with re- Djallon’s isolation and river blindness epidemics, a study by the na- gards to food security issues. The development of agriculture is ac- tional fisheries department looking at continental fishing found that companied with the use of fertilisers and phytosanitary products, fishing in rivers and adjoining seas plays an important role in food where frequent long-term use can damage water quality. An overly security and the creation of jobs for rural communities in the sec- high concentration of fertiliser can lead to plant overgrowth in rivers tor. According to this study, the average landing figures per fisher and dams, and phytosanitary products are toxic for human health would be comparable to those in the Senegal upper valley (around and the fish population. In the Guinea portion at the heart of Fouta 2.6 tonnes/fisher and per year on average). Constraints in terms of Djallon, the use of pesticides and fertilisers remains quite low com- fishing in Fouta Djallon are mainly linked to the rarity of the resource pared with the situation in Guinea. Pesticides are “rarely” used in the on the one hand and a lack of equipment on the other. In the Fouta Fouta Djallon highland. In 2016, around 95,000 tonnes of pesticides Djallon highland’ extended area RPID, the sectors of Kéniéba, Baoulé were received in the 15 prefectures of the Fouta Djallon. This is 18% (in the Baoulé biosphere reserve) and Bakoye are also deemed to of the total tonnage received in Guinea (figure 39). The highest be significant fishing sectors. The Kayes lowland region is deemed to consumer is the region of Nzérékoré followed by Kankan, sugges- have strong natural fishing potential which is now even higher in this ting that the Niger basin is more exposed to these products. The sector due to the presence of the Manantali dam which attracts many quantities of fertiliser received at 15 prefectures in the Fouta Djallon fishers, particularly from the Niger basin. The average annual landing highland amounts to nearly 4,100 tonnes/year. By adding partially per fisher in Manantali is estimated at 10 tonnes/fisher and per year, covered prefectures, this tonnage rises to 7,600t, i.e. nearly 66% of 7 prefectures partially associated to RPID 15 prefectures associated i.e. around 1000 tonnes/year (map 34). At the RPID extended area the “fertiliser” input in Guinea. In its specific survey on the use of Fouta Djallon highland to RPIDFouta Djallon highland covering the Niger basin, fishing activity remains significant although inputs in the Senegal basin, it tends to show applied doses of around most of the activity in Mali is located in the Niger inner delta (80% 2 to 5 kg/ha for pesticides (Mali zone) and doses of Nitrogen-Phos- Figure 39 > Contribution of the prefectures of Guinea in the of Mali total i.e. 40,000 to 120,000 tonnes/year depending on the phorous-Potassium (NPK) between 4kg/ha (Rice, maize) and 22kg/ year). Production linked to the Sélingué dam on the Sankarani is esti- ha (millet). total use of pesticides in Guinea mated at around 3,000 tonnes/year. The remainder of fishing activity Fisherman on Niger river banks at Bamako is scattered along the Niger for both the Guinea and Mali portions and is mainly focused on navigable portions. Finally, very far away from the Fouta Djallon, there is also estuary and sea fishing in pro- gress in Guinea, The Gambia and Sierra Leone, which is a much more significant activity than continental fishing in these countries. FOUTA DJALLON HIGHLAND WATER ATLAS • WATER USES IN THE FOUTA DJALLON HIGHLAND Arti cial Map 34 lake of > Artificial lakeManantali dam of Manantali dam on Ba on Bafing ng river river (Kayes (Mali - Kayes region) region) -10.6 -10.5 -10.4 -10.3 -10.2 -10.1 13.2 13.1 Reservoir and facilities River Ba ng Situtation Région de Kayes Altitude of the reservoir 208 m Volume of the reservoir 11 000 millions of m3 Area of the reservoir 47 700 ha Installed capacity 200 MW 13.3 Annual production 740 GWh / year irrigated area 255 000 ha Fishing (data 2009) Nomber of shermen 540 Annual landing (Tons) 1000 t Potential productivity 65 kg / ha / year Third zone of halieutic production of Mali Projection latitude - longitude WGS 84 - Géohyd , Global Land Cover Facility, ETM mosaic Created by Géohyd Anteagroup - Axel Aurouet 2017 12.9 79 HYDROELECTRIC POWER POTENTIAL OF FOUTA DJALLON LE THE FOUTA DJALLON’S HYDROELECTRIC POTENTIAL, LINKED TO THE POWERFUL WATERFALLS LOCATED IN IT, HAS BEEN IDENTIFIED FOR A LONG TIME. ITS POTENTIAL CAPACITY IS THUS ESTIMATED TO BE APPROXIMATELY 2,600 MW, WHICH IS 47% OF GUINEA’S POTENTIAL. THERE IS AN ESTIMATED POTENTIAL CAPACITY OF 2,800 MW FOR THE TERRITORY OF MARITIME GUINEA. HYDROELECTRIC DEVELOPMENT PROJECTS IN THE HIGHLANDS OR ON THEIR BORDERS HAVE INTENSIFIED IN RECENT YEARS, IN KEEPING WITH NATIONAL AND TRANSBOUNDARY ISSUES. A LONG-TERM AND MULTI-LAYERED INSTALLED POTENTIAL REGION POWER STA- CAPACITY RIVER BASIN HEIGHT (M) COMMISSIO- GROUPS TION NAME NING (MW) Hydroelectric power is a major issue for Guinea but also more ge- nerally for all countries bordering the rivers coming from Guinea. Kindia Banéah 5,00 Samou KONKOURÉ 19,5 1969 2x2,5 MW The Gambia has indicated an ambition to meet its entire electricity Kindia Donkéa 15,00 Samou KONKOURÉ 74 1965 2x7,5 MW demand by 2020 and Guinea wants to increase electricity access by Kindia Garafiri 75,00 Konkouré KONKOURÉ 56 1999 3x25 MW 50%. Mali and Senegal continue to actively develop their hydroe- lectric power and Sierra Leone wants to triple its installed capacity 2x5 MW + Kindia Grande chutes 27,00 Samou KONKOURÉ 115 1953 by 2020. The numerous and powerful waterfalls in the Fouta Djal- 2x8,5 MW lon, like in other regions in Guinea, have attracted attention for this Kindia Kaléta 240,00 Konkouré KONKOURÉ 49,2 2015 3x80 MW potential, which is estimated at around 26,000 GWh/year for the Mamou Kinkon 3,40 Kokoulo KONKOURÉ 110 1966 4x0,85 MW entirety of Guinea. The “technically feasible” potential would be around 19,300 GWh/year and the “economically feasible” potential Nzérékoré Loffa 0,16 Ouin-ouin LIBERIA 24 1958 1x0,16 MW at around 18,200 GWh/year. This “economically feasible” potential Kindia Samankou 0,16 Samankou FATALA 70 1995 1x0,16 MW represents 5,500 MW of raw power, of which 50% are estimated in Maritime Guinea and 47% in Central Guinea in the Fouta Djallon Faranah Tinkisso 1,65 Tinkisso NIGER 60 1970 3x0,55 MW highland (figure 41). Within this overall potential, the part estimated Sérédou Sérédou 0,64 Loffa Loffa ? for “small-scale” hydroelectric power still amounts to nearly 12,000 Table 6 > Main hydroelectricity facilities in Guinea (2016) GWh/year, so 46% of the total potential. This small-scale hydroelec- tric power, with an average capacity between 3 and 10 MW, could Konkouré, has three facilities commissioned between 1953 and 1969 Konkouré, with 75 MW and a useful volume around 1200 Mm3 for a produce nearly 2,845MW at around 111 sites across Guinea, whe- located to the north of Conakry. This complex has a dual purpose fall height of nearly 56 m. Set up in 1999 for use in the 2000s, it sup- reas current production is around 5.1MW for this type of facility. of power distribution and the supply of drinking water on the Co- plements power supply for Conakry, without ever managing to cover Currently the installed power in Guinea is estimated at around 368 nakry-Kindia axis. It has 47 MW distributed between, from upstream the entire demand. The dam has led to the creation of an artificial lake MW including the recent commissioning of the Kaléta works, which to downstream, the Baneya or Banéah dam (264 Mm3 with a 5 MW measuring nearly 79 km² but has also caused a strong modification in itself contributes 240 MW. Despite this, the Guinea potential remains production capacity plant), the Kalé dam associated with the Donkéa the hydrological regimes of Konkouré and, as a result, has led to softe- very underused: less than 7% (figure 40). production plant (9Mm3 for a 15 MW production capacity plant) and ning of estuary waters. Finally, the recent Kaléta dam is also positioned the Grandes Chutes dam (1 Mm3 with a 27 MW production capacity on the Konkouré, the largest hydroelectric power generator with plant). The Banéah facility remains a regulated facility but overflows 240 MW of installed power. Its artificial lake covers a surface area of HYDROELECTRIC POWER STILL UNDERUSED are still possible considering the average annual inlets estimated at nearly 2.82 km² for a stored volume of nearly 23 Mm3. Other facilities IN GUINEA BUT USED OUTSIDE OF GUINEA 353 Mm3. The Kinkon facility, located in the centre of Fouta Djallon in Guinea are smaller. On the Niger river basin, on the Tinkisso course on the Kokoulo and near to Pita, dates from 1966. With an installed to Dabola, there is also a concrete facility with a fall height of 60 m and THE KOUKOURÉ BASIN, THE TOP HYDROELECTRIC POWER power of 3.4 MW, it is a concrete facility overlooking a near 110 m an installed capacity of 1.5 MW which aims to serve Dabola, Dingui- PRODUCER IN GUINEA waterfall, but the retained volume is quite low (<3  Mm3) and does rate and Faranah. This facility does not regulate the Tinkisso and offers The Konkouré river is by far the most used river basin with a concen- not allow regulation of the Kokoulo. This facility supplies the towns of a minimum guarantee on its electrical production during low water. tration of over 99% of Guinea’s hydroelectric power generation (table Pita, Labé, Dalaba and Mamou, and its maximum productivity seems Finally, micro-plants, such as Sérédou (0.64 MW) and Loffa in Macenta 6). The complex of Samou, a Badi tributary, itself a tributary of the to have never been reached. The Garafiri dam is positioned on the (0.14 MW) seem functional, even if they do not cover the local needs. FOUTA DJALLON HIGHLAND WATER ATLAS • WATER USES IN THE FOUTA DJALLON HIGHLAND MANANTALI AND SÉLINGUÉ, HYDROELECTRIC POWER FROM WORKING TOWARDS DEVELOPMENT OF region on the Loffa basin (towards Liberia). Finally, no less than 11 GUINEA hydroelectric power projects are currently undergoing discussions. HYDROELECTRIC POWER IN THE FOUTA This includes the projects of Amaria (285 MW on the downstream The Manantali dam in Mali has a direct link with the Fouta Djallon highland as it is positioned on the lower course of the Bafing in DJALLON HIGHLAND’ WATERS WITH course of the Konkouré), Tiopo (90  MW), the Grand Kinkon Mali. It controls nearly 50% of the Senegal upstream basin’s inlets TRANSBOUNDARY CHALLENGES (280 MW on the Kokoulo, Konkouré slope), Balassa (181 MW on the and started operating in 1987. It helps control floods, stabilise Guinean Bafing before entering Mali), Digan (128 MW), Kora Findi GUINEA HYDROELECTRIC POWER ON THE RISE... (100  MW), Djolol Yillabhé (72  MW), Diaraguéla (72  MW on the downstream activities during low water periods (drinking water, irrigation, rain-fed cultivation, sailing), and produce energy Hydropower development projects in Guinea quickly rise (map 34). upstream course of the Niger), Fello Soungan (53  MW) and the (800  GWh/year) shared between Mauritania, Senegal and Mali. Its After the recent commissioning of the Kaléta plant, the Souapiti pro- N’Zébela (20 MW on the Diani-Vano slope towards Liberia). In ad- storage volume is considerable (11,000 mm3) and helps store the ject, 6 km upstream from Kaléta on the Konkouré, is currently being dition, smaller capacity projects are also being considered, such as equivalent to an average flow year in Bafing. Its completion was built with a planned power of nearly 515 MW, i.e. double that of Ka- Sérédou (2.25 MW on the Véré), Lokoua (6MW on the Loffa slope), carried out by the OMVS (Senegal River Development Authority) léta. At the same time, no less than 441 MW installation at the centre Nongoa (8 MW on the Makona slope), and Fouguia (3.2 MW on the by country delegation. Currently, the Manantali’s actual production of the Fouta Djallon highland were part of a feasibility study carried Tinkisso). Whilst not all of these projects will be carried forward, this seems to be around 740  GWh. Electricity produced at Manantali out at the Koukoutamba (294  MW) and Bouréya (161  MW) sites project dynamic underlines Guinea’s position with nearly 1,150 MW is distributed towards Bamako, Nouakchott and Dakar by over for the Fouta Djallon part of the Bafing (Senegal DB). The Fomi dam in a very advanced construction phase (over 3 times its current ca- 1,500 km of high voltage lines. The Sélingué dam, whilst dependent (90 mW installed power) on the Niandan (Niger DB) is currently un- pacity), 148 MW during the pre-feasibility stage and 1,218 MW in in part of the Guinea waters by the Sankarani, is not directly linked dergoing a feasibility study, as well as the Poudaldé facility (90 MW) the prior study phase. to Fouta Djallon. With a surface area of 460 km², its artificial lake has on the Kogon slope in the Boké region. Excluding Fomi, all of these a capacity of nearly 2,700 mm3 for an installed power at the dam projects are linked in some way to the Fouta Djallon highland and of around 44  MW (247 GWh/year). Built in 1980 and renovated their potential. Other projects are currently in the pre-feasibility between 1996 and 2001, this dam produces nearly 30% of Malian stage, which is the case for Morisanako, on the Sankarani (Niger DB) production and is an energy supply for the south of Mali. with a 100 MW power and Gozoguezia (48 MW) in the Macenta Hydroelectricity potential, Figure 40 > Hydroelectric potential, operation and exploitation and operating exploitation project project linkedlinked with with Fouta Fouta Djallon Djallon highland highland Hydroelectricity potential of Guinea Share of exploitation of hydroelectricity potential Share of advanced hydropower projects in coastal Guinea and central Guinea in unexploited potential Coastal Guinea Central Guinea in coastal Guinea and central Guinea 2 800 MW (Fouta Djallon) 2 600 MW without advanced project - 79 % d potent ite ia lo l ( p ex 93 Un %) 1 % other 5 % Kaléta 1 % Gara ri 10 % Souapiti Upper Guinea 6 % Koukoutamba 3 % Bouréya Forest Guinea 2 % Poudaldé 81 HYDROELECTRICITY Koukoutamba site ... INTERCONNECTED WITH THE SUB-REGION Whilst these projects are effectively located in Guinea, some of them missioning of the Kaléta facility. The main effects of these facilities can involve much larger transboundary cooperation challenges. The therefore be, potentially: most emblematic project is that of Kaléta where the construction • The general modification of flow regimes, project is part of a transboundary interconnection framework with • Interception of solid flows and destabilisation of the sediment regime, the Sambangalou hydroelectric power dam project in Senegal, with • The flash suspension of sediments 128  MW power, on the Gambia river on its exit into Guinea. This • Collapse of downstream banks under the effect of daily flow variations, project, funded through the Gambia river development authority • Immediate downstream damage to the aquatic environment (flora & (OMVG), estimated at nearly 654  M USD, is part of the Kaléta fauna), and Sambangalou construction project and their interconnection • When the facilities are not too distant from estuary zones, modifica- to supply OMVG member states. No less than 1660  km of tion of the estuary salt front and people associated with these condi- interconnections are planned as part of this project. Whilst Kaléta’s tions. construction is complete, Sambangalou’s construction has not yet • Finally it is also necessary to underline that artificial dams caused started. The Koukoutamba and Bouréta hydroelectric power dams by these major hydraulic facilities cause a net loss of resources by are also a transboundary interest and are both part of the Senegal evaporation of the stagnant flow depth. With its 79 km² lake and river development authority (OMVS) for a cost of around 1,094 M average evaporation of 1500 mm/year, potentially over 118 Mm3 of USD. They also have an interconnection phase with OMVS member water is lost over the year on a Garafiri-type facility, i.e. the equivalent states. Finally the Fomi dam on the Niandan is carried out by the of 3.8m3/s or even 7% of the total stored volume. Niger Basin Authority (ABN) for the total estimated sum of 503 M USD. MULTIPLE CHALLENGES FOR SURFACE WATER RESOURCES, SUCH AS GARAFIRI During a study of the impacts of the Garafiri dam (Ferry et al., 2003), other than the modification of flows through flood reduction and increased low level flows, it is underlined that this facility has a si- gnificant impact on the salt front of the Konkouré during low water periods. In comparison, it seems that this fall has led to a progres- sive disappearance of certain oyster populations on estuary sectors on the Konkouré. It should be noted that for this dam the sediment transport assessments are in the lower fork, upstream from the dam rather than in the dam. The highest concentrations in depth are also more linked to iron oxide precipitation than accumulation of suspended particles from upstream zones. Nevertheless, it is under- lined that the daily flow variations should play a significant role on downstream sediment, notably by remobilising sediments and by causing bank collapse. These daily fluctuations also affect dissolved oxygen downstream and therefore the immediate aquatic environ- ment. Before entering the Konkouré estuary, the quantity of sus- pended materials has been estimated between 91,000 and 127,000 tonnes per year. These measurements were taken before the com- Kokoulo river, nearby Kinkon hydropower plant FOUTA DJALLON HIGHLAND WATER ATLAS • WATER USES IN THE FOUTA DJALLON HIGHLAND Hydroelectricity facilities Map 35 > Hydroelectricity and facilities and project linked hydroelectricity with projects linkedFouta Djallon with Fouta highland and its extension zones Djallon highland 15.0 -15.0 -10.0 DAKAR FELOU (60 MW) MANANTALI (200 MW) GOUINA (140 MW) BANJUL GAM BIE E FA L E M SOTUBA (5,7 MW) YE SAMBANGALOU (128 MW) O BAMAKO AK ING B POUDALDE (90 MW) BAF Bassin du Konkouré BISSAU DIAOYA (148 MW) SELINGUE(46 MW) GRAND KINKON KOUKOUTAMBA (280 MW) (280 MW) BOUREYA (161 MW) R GE NI KALETA (240 MW) FOMI (90 MW) AMARIA (285 MW) MORISANAKO (100 MW) GRANDES CHUTES (27 MW) Legend BANEAH (5 MW) Topographic highlands DONKEA (15 MW) Fouta Djallon 10.0 BALASSA (181 MW) Guinean Dorsal Coastal Guinea CONAKRY Banié - Niandan KASSA B (100 MW) Hydroelectricty project GARAFIRI (75 MW) Advanced engagement Development in progress Existing facilities FREETOWN Potential site NZEBELA (49 MW) SOUAPITI (450 MW) 200 MW 50 MW 15 MW Operating capacity Projection WGS 84 - Source 2016 Geohyd, world Atlas hydropower and dam, sieguinée - Creatd by Géohyd Anteagroup - Axel Aurouet 2017 83 MINING BAUXITE DEPOSITS CONSTITUTE THE MAIN MINERAL WEALTH OF THE HEART OF FOUTA DJALLON HIGHLAND. SOME SIGNS OF DIAMOND SHOW UP IN THE FOUTA DJALLON PART OF THE GAMBIA RIVER, AND THE GUINEAN PART OF THE BAFING VALLEY SHOWS TRACES OF GOLD. ITS EXTENSIONS, ESPECIALLY THOSE LOCATED IN THE GUINEAN HIGHLANDS, MAINLY CONTAIN GOLD, DIAMONDS AND IRON. BAUXITE, THE MAIN MINERAL RESOURCE IN Gites or clues of minerals in the heart of the Fouta Djallon highland Map 36 > Gitology or evidence of ore in heart of Fouta Djallon highland THE FOUTA DJALLON HIGHLAND S E N E G A L Bauxite is a major mining resource in Guinea and it is also the main mi- ning resource in the Fouta Djallon highland (map 36). We note here that I M A L é K Falé m Guinea’s bauxite resources are recognised as the largest and richest in o u Ko the world. They are assessed at nearly 40 billion tonnes including 20 u n tou lo ul ko billion reserve tonnes currently proven. The breadth of these estimated g ou G a n am Go m bo reserves would supply the world aluminium industry for approximately MALI n b nd ie a ko u B 3 centuries. Bauxite deposits are mainly focused on the south-west part Ko 12.0 tal a é of Guinea, in the Boké region (>12,000 million tonnes), in the Kindia-Fria m an B la sector (>1,700 million tonnes) and in the Fouta Djallon highland (>1,500 Si b ie million tonnes). In the Fouta Djallon highland, there are also some scatte- Kol Koet red diamond deposits or areas in the Labé - Koubia sectors and in the a ib m a a Mali zone, nickel deposits or areas to the south-east of Labé and some G gold deposits or areas in the south part between Mamou and Faranah KOUBIA and in the north zone of Dinguiraye which extends to the east in the TOUGUE 12.0 Siguiri zone. In the South-east zone of the Fouta Djallon highland, in the LELOUMA ng a Faranah sector, on the border with Sierra Leone, there are also corun- B Ki o dum deposits or areas (mineral made of aluminium). Finally, we note that LABE DINGUIRAYE m a the extraction of carbonated rocks (limestones - dolomites) take place in L the highland at the enclosed valleys of the Bafing and the Gambia. PITA a a uk ri m Bo 11.0 lo Kak ko u Té n é so is TELIMELE k Ko g n Ti Ba n DABOLA Legend DALABA N Bauxite Carbonate rocks ian tan Iron Monazite K onkour é r ge 11.0 Gold Nickel Ni Corundum Uranium (clue only) MAMOU Copper ngo Observed or Chromium K Diamond interpreted fault a Kab ol Mo en KINDIA té FARANAH Mafou er 10.0 S I E R R A Nig -13.0 -12.0 L E O -11.0 N E Source : Ministry of Mines, Géology and Environnement - map « des Minéraux utiles de la république de Guinée » (2006) FOUTA DJALLON HIGHLAND WATER ATLAS • WATER USES IN THE FOUTA DJALLON HIGHLAND MINERAL RESOURCES IN THE FOUTA DJAL- to Senegal, there are zones with copper and chrome. Copper and ment) - Member States must minimize geological, political and econo- chrome deposits are also identified in Guinea downstream from the mic risks by managing the allocation of mining claims and by setting up LON HIGHLAND’ EXTENDED AREAS Rio Corubal (Koliba) and Koulountou. Finally, in the downstream environmental management policies. Funding set up to build geolo- The Fouta Djallon highland’ extended area has significant mineral part of the Bafing, at its confluence with the Bakoye, iron mineral gical and mining infrastructure (mapping, databases, mining cadastral diversity and richness, directly linked with the resources in Guinea zones with marble mining are indicated. systems have really ensured an important development of the sector (map 38). The upper Niger zone, in the Guinea regions of Kankan since the 1990s, with many mine openings. Today, the countries of the and the extension towards the south-east of Mali, has a significant MACRO-ECONOMIC ASPECTS OF THE MI- Fouta Djallon highland area all more or less strongly depend econo- gold wealth, notably in the Banié-Niandan chain sector, bordering NING SECTOR IN THE AREA mically upon this sector (map 37). In many countries such as Guinea, the Siguiri basin and extending towards the west to the Fouta Djallon Mali, Burkina Faso or Côte d’Ivoire, placer mining remains the largest highland’ foothills. Further south, in the Kérouané sector, there are Following the colonial period, at the beginning of the 1990s, most mining «employer» (more than one million people estimated for Gui- many gold and diamond deposits extending to the Forest Guinea African States, the World Bank and the European Union all reco- nea). Industrial operations generate a few thousand salaried jobs on border. Diamond zones are found in the Bamako sector. In the Ké- gnized that the mining sector was the only realistic option for short the national level, which is far from negligible. Although they are far rouané sector, there are also mined iron deposits in the Simandou term development in a region with very little skilled labor, provided behind public service employment, these jobs, which are usually paid mountains. Directly to the north of the Fouta Djallon highland, on the it was entrusted to the private sector (OECD, 2002). The World Bank correctly and mostly located outside of main urban areas, have a ma- Mali-Guinea border, there are several uranium areas. The Falémé val- then implemented a development strategy based on two principles: jor social impact: a salary in the bush provides a livelihood for 10 to ley, in its upstream course leaving Guinea, has iron and gold mineral - Exploration and operations are high-risk investments that should be 15 people. Thus, there are indirect benefits for neighboring villages, wealth. Further afield, in its downstream part and in the extension done by the private sector (foreign direct investment and local invest- especially in terms of trade development. Map 37 > Importance Importance of mining de la rente in countries incomedans minière linekd les pays entolien Fouta Djallon avec highlanddu Fouta Djalon (2015) le massif -20.0 -15.0 -10.0 -5.0 0.0 Mauritania 15.0 Senegal Mali Niger The Gambia Legend % of GDP of the country Burkina Faso Guinea-Bissau 0% or no data 0 to 5 % 5 to 10 % Guinea 10 to 15 % Fouta Djallon highland Benin 15 to 20 % and surrounding highlands 10.0 20 to 30 % Mineral rents are the di erence between the value of production for a Sierra Ghana Togo stock of minerals at world prices and their total costs of production. Leone Minerals included in the calculation are tin, gold, lead, zinc, iron, copper, nickel, silver, bauxite, and phosphate. Ivory Coast Estimates based on sources and methods described in "The Changing Wealth of Nations: Measuring Sustainable Development in the New Liberia Millennium" (World Bank, 2011). Projection latitude - longitude WGS 84 - Source : World bank - Created by Géohyd Anteagroup - Axel Aurouet 2017 85 MINES MULTIPLE POTENTIAL IMPACTS OF MINING ACTIVITY ON WATER RESOURCES FROM A QUANTITATIVE POINT OF VIEW ON WATER QUALITY The industrial mining sites consume water in large quantities for do- Hydro-metallurgic treatments are considered the main source of wa- mestic living purposes, but also for mining activity (watering tracks, ter pollution by the mining industry. In Guinea, two processes are a rinsing equipment, etc.) and even more for industrial processes. For major environmental and health concern: gold cyanidation and alumi- example, in Kamsar (Boké region), the wet drying dust recovery pro- na production. Processing processes for bauxite, a major resource in cess uses 2,400 m3 of water per day and in Sangaredi (on the Kogon), the Fouta Djallon highland, generate sediment waste called “red mud” a daily pumping of nearly 4,500 m3 is carried out with 30% industrial which is very acidic and toxic. In service between 1960 and 2012, the water and 70% drinking water. Finally, the main water resource used Fria plant was the only alumina production unit in Guinea with a red is the surface water by direct pumping from the river. Whilst these mud volume up to 1 Mm3/year which was carelessly spilled into the water uses do not pose a specific problem during high and middle Konkouré for many years (picture below). The situation has improved water periods, drying-up periods are sometimes quite critical on ri- from 1993 with the creation of dams and reservoirs to store the mud. vers where the flows tend towards 0. The impacts on underground But the break in the upstream dyke due to strong rains in 2007 and waters can be present in surrounding pits and boreholes, notably 2009 demonstrated that the river is not free from major pollution. in the pumping range where they exist. Finally, one of the major im- Acid mining drainage is another possible consequence of mining ac- pacts of the mining industry in Guinea is certainly the increase in tivity on water and aquatic environment quality. As a result, significant sediment load. By exposing the large land surface areas, mining in- volumes of sulphur-rich rocks are exposed to water and atmospheric dustries increase erosion process. oxygen, and this leads to metal acid pollution in groundwaters. Spillway of sludge’s dam downstream of Fria complex ( January 2002) FOUTA DJALLON HIGHLAND WATER ATLAS • WATER USES IN THE FOUTA DJALLON HIGHLAND Map 38 of Areas ore or > Gitology ore area or indices in evidence of Fouta ore Djallon in Fouta highland Djallon highland and its zones extension zones and its extension -15.0 -10.0 15.0 15.0 DAKAR Copper - Chromium - Marble M A N D I N G M O U N T S Iron & Marble Iron & Gold Uranium BANJUL (IIndices only) S I G U I R I N I B A L E A H I G H L A N D BAMAKO BISSAU F O U C O A S TA L H I T A D JA LL GH ON Diamond & Iron LA Copper & Chromium D N 10.0 10.0 G Bauxite U CONAKRY N I E A N Iron in Simandou chain Corundum D O Iron & Bauxite R S A L Iron FREETOWN Iron - Diamond & Talc Diamond Gold Diamond & Gold -15.0 -10.0 Sources : Niger basin observatory, SDAGE OMVS and analysis of Gitology map of Guinea - projection WGS 84 - topographic highland from Luc Ferry (2017) - Created by Géohyd Anteagroup - Axel Aurouet 2017 87 SUMMARY ON WATER USES By and large, eight countries are concerned by the Fouta Djallon highland, through the main livestock farming areas in Guinea with approximately 4.2 million head of cattle. RPID project for the Fouta Djallon. The inventory of populations really influenced by the Agriculture in the Fouta Djallon is sometimes held responsible for soil erosion. There is Fouta Djallon highland in all eight countries (based on the segmentation of the RPIP-FDH little consensus in the literature regarding this causal relationship even if, from a quality project) has never been undertaken. However, we can estimate the population to be perspective, clearing practices, overgrazing and slash-and-burn techniques remain sus- approximately 15 million inhabitants, including 5.7 million for Guinea. This population in- ceptible to degrade soils broadly. ventory further emphasizes the important place that the Fouta Djallon highland occupies for the riparian populations of the rivers. However, the population most «dependent» The hydroelectric potential of the Fouta Djallon highland, currently estimated to be upon the Fouta Djallon highland remains Guinea. With close to 3.25 million inhabitants 26,000 GW for Guinea, has been identified for quite some time. The highland represent in the prefectures located at the heart of the Fouta Djallon highland, and 5.7 million with close to half of Guinea’s potential. The other half is concentrated in the southern part the aggregation of neighboring prefectures, more than half of Guinea depends upon of Guinea, in the coastal Guinea mountains, but it mainly concerns waterways originating the Fouta Djallon and its resources. The region remains remote, with moderate access to in the Fouta Djallon. Nowadays, this potential is starting to be harnessed to a significant roads. The rate of access to safe drinking water was 47% at the beginning of the 2000s, degree with the construction of the Kaléta and Souapiti dams, in addition to the Garafiri and the poverty ratio was among the highest in Guinea. dam which is older. Agriculture in the Fouta Djallon highland employs approximately 85% of the population, The Fouta Djallon is a significant mining reserve. Bauxite (rock with a high alumina and iron using traditional practices based on clearing and slash-and-burn techniques. «Tapades», oxides content) constitutes the main deposit at the heart of the Fouta Djallon highland, which are an agrarian system originating in the Fouta Djallon, are a specific marker of and gold deposits are present in the northeast extension of the Fouta Djallon highland, this area. These are the mixed areas of residence, domestic husbandry and enclosed in the Bafing valley. Gold, diamond and iron deposits are found throughout the Guinean gardens, listed under the «Globally Important Agricultural Heritage Systems» (GIAHS) Highlands. This mineral wealth represents an important resource for economy of the by the FAO. Although cassava remains the main agricultural production with maize and Fouta Djallon, and more widely, for Guinea. Gold and copper deposits are also found in potatoes, fonio is a crop that can be found in much of the Fouta Djallon plateaus, which the extensions of the Fouta Djallon highland, in Senegal and Mali. are the leading producing areas for it in Guinea. The Fouta Djallon is also one of the FOUTA DJALLON HIGHLAND WATER ATLAS • WATER USES IN THE FOUTA DJALLON HIGHLAND Production and Map 39> Production share and production ofproduction share of of of fonio fonio inside in Guinean Guinean prefectures prefecture of Fouta Djallonof Fouta Djallon (2016) Highland -15.0 -14.0 MEDINA GONASSE -13.0 -12.0 -11.0 -10.0 KITA -9.0 13.0 KOLDA SEDHIOU S E N E G A L Prefectures associated to Prefectures partially associated to RPID Fouta Djallon RPID Fouta Djallon M A L I U NOVA LAMEGO KOUNDARA S A BAFATA KANGARA MALI I S BISSAU 12.0 B BOLAMA N E A GAOUAL KOUBIA I U TOUGUE SIGUIRI G LELOUMA LABE DINGUIRAYE BOKE PITA 11.0 TELIMELE DALABA MANDIANA KOUROUSSA DABOLA FRIA MAMOU KANKAN BOFFA Legend KINDIA FARANAH DUBREKA Share of production 10.0 in total production of the prefecture (%) COYAH KABALA < 1,5 % CONAKRY KAMAKWIE KEROUANE 1,5 à 5 % FORECARIAH KISSIDOUGOU 5 à 7,5 % L E O 7,5 à 10 % R R A N 10 à 15 % KAMBIA I E S 9.0 E 15 à 34 % MAKENI Production in Tons PORT LOKO 70 000 tons GUECKEDOU MACENTA BEYLA 30 000 tons FREETOWN 10 000 tons 2 000 tons KAILAHUN Projection latitude - longitude WGS 84 - Géohyd - Ministry of agriculture of Guinea (census 2016) - Created by Géohyd Anteagroup - Axel Aurouet 2017 89 WATER CHALLENGES IN THE FOUTA DJALLON HIGHLAND FOUTA DJALLON HIGHLAND WATER ATLAS AND RESPONSES GIVEN This chapter identifies the issues of biodiversity protection, water-related conflict and water governance in relation to the major driving forces of predictable impacts related to climate change. It gives an overview of the situation and issues in the Fouta Djallon highland and its extension areas. 91 REMARKABLE NATURAL SPACES AND SPECIES THE FOUTA DJALLON HIGHLAND CONTAIN OUTSTANDING NATURAL AREAS WITH CLOSE TO 56 FOREST RESERVES AND THE RECENT CREATION OF THE BAFING NATIONAL PARK. THE FOUTA DJALLON HIGHLAND PROVIDE A HOME FOR LARGE POPULATIONS OF CHIMPANZEES ACROSS WEST AFRICA, AS WELL AS OTHER IMPORTANT SPECIES. THEIR BIODIVERSITY IS VERY RICH BUT REMAINS FRAGILE. PROTECTED AREAS of 6470 km² and Kouya (6000 km²) with a rich and diverse biology Chimpanzee known for birds (323 different species), insects and large mammals There are nearly 64 classified forests in the natural region of Central (monkeys, leopards, buffalo, cobs, etc...). Guinea (map 40) which cover most of the Fouta Djallon highland. In the contours of the Fouta Djallon highland, there are 56 classified FOUTA DJALLON FAUNA forests in the Guinea portion, 1 forest reserve in Sierra Leone (Kuru Hills) and a scientific interest zone for flora in the Mali extension of Inventories completed in the Fouta Djallon highland area and more the topographical highland. In addition to these spaces, a national generally in Central Guinea show the diverse fauna in this area. There park was created in Middle Bafing on the Bafing slope between the are jackals, leopards, cows, hippopotamuses, monkeys, red colobus, sources of the Bafing until it exits into Guinea. The number of protec- baboons and chimpanzees. The Fouta Djallon chimpanzee popula- ted forests in Guinea is very limited and are found in Lower Guinea, tions are the largest in the sector of West Africa (nearly 17,700 indi- Upper Guinea and Forest Guinea outside of the topographical Fouta viduals) with an increased number in the Middle Bafing national park Djallon. Their inventory has not been completed in full. In the Guinea (4,700 to over 5,500 individuals noted). The specific zone of the extended areas, all ecosystems in the Guinea coastal river outlets and Middle Bafing national park is also a zone which is subject to various Guinea Bissau (mangroves) are recognised as “internationally impor- dam and mining projects (inactive for the moment) which require tant wetlands” and there is the Badiar national park to the north-west vigilance regarding preservation of these chimpanzee populations of Guinea on the border with Senegal and on the Gambia basin. in this region. We also note the presence of the Niokolo Koba National park in the south-east of Senegal, considered as a biosphere reserve and THE MAIN THREATS TO ENVIRONMENTAL part of the UNESCO world heritage list, and a chimpanzee reserve DAMAGE in Mali, near Kéniéba, known as the Bafing chimpanzee sanctuary. Other than climate changes which can modify ecosystems and the Finally, in the eastern foothills of Fouta Djallon, there is the Upper habits of the animal populations which live there, the main threats to Niger National Park made up of 2 sectors: Mafou for a surface area this natural heritage are agro-pastoral activities through soil damage, the introduction of improved varieties, destructive insects, cultural nomadism, brush fires which destroy the plant populations and fauna habitats, carbonation, hunting, fishing, forest exploitation, mining and industrial activities, major hydroelectric power facilities and urbani- sation through reduced natural spaces in favour of artificial spaces. All those factors need to be controlled or anticipated to reduce da- mage to the natural areas of the Fouta Djallon. Bubal FOUTA DJALLON HIGHLAND WATER ATLAS • WATER CHALLENGES IN THE FOUTA DJALLON HIGHLAND Protected areas Map 40 > Protected linked areas with linked with Fouta Fouta DjallonDjallon highland highland and and its extension its extension zones zones -15.0 -10.0 F e r lo 15.0 15.0 Sé né DAKAR S E N E G A L ga l M A L I u lé UNESCO Biosphere reserve B ao Delta du Saloum Ba bie k oye G am é lém BANJUL T H E G A M B I A Fa g r a n ge Ni Kou National park of Niokolo Koba am B G bi l ou e Gé a BAMAKO nt National park of Badiar b ou G U I N E A - Koliba ba Gé l Ga ba U B I S S A o ru Bag o é UNESCO Biosphere reserve m n g BISSAU F C Ba bie r Bolama Bijaros KombO ge aU C O A S T A L Ni T To m i n é Tinkisso Ko A a lé go Baou i r im n D Nu n Fié ran Téné ez A BANIE-NIANDAN J R io K ak o oul A Sanka CHAIN L T ok K ng LO Ba L H I ré G U I N E A er la N ig N ta ou ng o Milo Fa A G K o nk a B H K ab nt é Mo adL Legend N 10.0 u National park n i A Mafo K ole nd a of Moyen Ba ng N T lé Forest reserve D G N ia K o u ro uk é cies s- U I N e CONAKRY I Classi ed forest rci E r Sca C Di o n ca A National Park e N ts Li tt l ea D I V O R Y Gr O O Faunal reserve k el R S A Ro c C O A S T C Reserve (Natural or ora)) E L A FREETOWN S I E R R A Bird reserve N L E O N E S e wa Jong Protected areas Coastal protected areas National park of Upper Niger ro Mo a a Mo Faunal sanctuary - S a s s a n d ra an a os Lo l C avally M u st Interested zone of ora Pa Ce t Nimba Mounts S ain Wetland protected zone L I B E R I A Woodland and pasture zone -15.0 -10.0 Projection latitude - longitude WGS 84 - Géohyd - topographic highland from L. Ferry, 2017 - Réalisation Géohyd Anteagroup - Luc Ferry & Axel Aurouet 2017 93 CLIMATE CHANGE AND ADAPTATION IPCC MODELS WITH REGARD TO THE EVOLUTION OF PRECIPITATION AND TEMPERATURE IN THIS REGION VARY. HOWEVER, CLIMATE CHANGE SHOULD EXACERBATE RAINFALL AND WATER VARIABILITY IN THE FOUTA DJALLON HIGHLAND. ADAPTATION PROJECT INITIATIVES HAVE ALREADY BEEN SUGGESTED THROUGH THE NATIONAL ACTION PLAN ON CLIMATE CHANGE ADAPTATION IN GUINEA. Whilst the issue of climate change is already well established in the of drought were experienced from the 1970s to the 1990s, after a rainy crease in rainfall in East Africa. There is a wide range of projections for rain- concerns of managing and planning water resources, items allowing a period during the 1950s and 1960s. The fall in rain was mostly linked to a fall in Sub-Saharan Africa, with some models predicting falls and others structured and precise discussion are still partial, patchy and sometimes reduction in the number of significant rainy periods during the monsoon increases. The planned trends must be considered in the context of this even contradictory. To date, in line with the very general GIEC guidelines, peak period ( July to September) and during the first rainy season to the significant uncertainty even if all experts agreed on a decrease in rainfall it seems to be noted that river hydraulicity is moving towards a decrease south at around 9°N. The reduction in rainfall and devastating drought in depth. in the sub-region. the Sahel region during the last three decades of the 20th century were part of the most pronounced climate change, all regions included. In the IPCC ANALYSIS ON THE SUB-REGION Sahel, rain reached a minimum after the 1982/3 El Niño episode. Mo- Climate change has been studied by various scientific teams, whose work delling studies suggest that Sahel rainfall was more influenced by climate has been regularly discussed and published as part of the GIEC. Over change on a large scale (probably linked to changes in anthropogenic the last century, the West Africa Sahel region has been dealing with de- aerosols) than local land allocation changes. For the African continent, simulations carried out on climate change indicate (figure 41) a conside- creased rainfallof Moving (mapisohyets between 41), linked to changes 1951 in atmospheric - 1969 circulation and period and 1970 - 1981 period rable variation from one model to the other. The strongest simulations D’après / From l’Hôte & Mahé changes linked to the configuration of surface sea temperatures in the tro- 20.0 -20.0 pical regions of the Pacific, Indian and Atlantic basins. Significant periods -10.0 warming and a fall in rainfall in North Africa and an in- highlight global 0.0 10.0 Map 41 > moving of isohyets between 1951 - 1969 and 1970 - 1981 period From l’Hôte & Mahé (1995) 250 250 A 250 T 600 L 250 15.0 DAKAR 600 250 A NIAMEY 600 250 N BANJUL 1000 BAMAKO 600 600 T 1000 600 I OUAGADOUGOU C Legend BISSAU 18 1000 00 Period O isohyet 1951 - 1969 1800 10 00 C E 10 10.0 isohyet 1970 - 1981 A CONAKRY 00 ABUJA Trend classes N of isohyets FREETOWN Isohyet 250 mm YAMOUSSOUKRO 18 00 LOME 1800 Isohyet 600 mm 1800 MONROVIA Isohyet 1 000 mm Topographic highlands of Fouta 1800 PORTO-NOVO Djallon, Guinean Dorsal and 18 ACCRA coastal Guinea 0 Isohyet 1 800 mm 0 Projection latitude - longitude WGS 84 - From l’Hôte & Mahé - IRD - Created by Géohyd Anteagroup - Axel Aurouet 2017 FOUTA DJALLON HIGHLAND WATER ATLAS • WATER CHALLENGES IN THE FOUTA DJALLON HIGHLAND Prévision de l’évolution Figure 41 > Predicting duinclimat Climate Change enAfrica Sub-Saharan Afrique Subsaharienne and North et Africa by 2100 - IPCC en Afrique du Nord à l’horizon 2100 - GIEC - 2013 2013 Prévision de l’évolution du climat en Afrique Subsaharienne et en Afrique du Nord à l’horizon 2100 - GIEC - 2013 Evolution of the EVOLUTION average OF THE surface AVERAGE temperature SURFACE (di erential TEMPERATURE between the (DIFFERENTIAL period 1986 BETWEEN THE-2005 and PERIOD 2081 -2100) 1986-2005 AND 2081-2100) Evolution of the average surface temperature (di erential between the period 1986 -2005 and 2081 -2100) RCP 2,6 RCP 8,5 RCP 2,6 RCP 8,5 Highlands of Highlands of Fouta Djallon Highlands of Fouta Djallon Highlands of area Fouta Djallon area Fouta Djallon area area (°C) -2 -1,5 -1 -0,5 0 0,5 1 1,5 2 3 4 5 7 9 11 (°C) -2 -1,5 -1 -0,5 0 0,5 1 1,5 2 3 4 5 7 9 11 Evolution of rainfall (di erential between the period 1986 -2005 and 2081 -2100) Evolution EVOLUTION of rainfall OF THE (di erential RAINFALL between the period (DIFFERENTIAL 1986 BETWEEN -2005 THE and 2081 PERIOD -2100) 1986-2005 AND 2081-2100) RCP 2,6 RCP 8,5 RCP 2,6 RCP 8,5 Highlands of Highlands of Fouta Djallon Highlands of Fouta Djallon Highlands of area Fouta Djallon area Fouta Djallon area area (%) -50 -40 -30 -20 -10 0 10 20 30 40 50 (%) -50 -40 -30 -20 -10 0 10 20 30 40 50 The maps represent the results of the CMIP5 multi-model averages for RCP2.6 (CO2 emission = 421 ppm) and RCP8.5 (CO2 emission = 936 ppm) over the period 2081-2100. For The mapsthe all maps, dashedthe represent linesresults indicateof the the CMIP5 regions multi-model in which the averages for RCP2.6 multi-model (CO2 average isemission = 421 large relative ppm) to and RCP8.5 the internal (CO2 natural emission(meaning variability = 936 ppm) over the greater thanperiod 2081-2100. two standard For devia- all maps, tions The mapsover the dashed 20 years represent lines averages) the results indicate and in of the CMIP5 the regions which 90 multi-model in which % at least averages the multi-model of models for RCP2.6 agree (CO2 emission average on the = 421 ppm) is signlarge and RCP8.5relative of change. to the In the = (CO2 emission internal rainfall 936 ppm) natural trend variability maps, over the periodthe (meaning lines represent 2081-2100. greater the For all maps, than thesectors two standard which forindicate dashed lines devia- averages the regions tions were in whichover modeled20 years for the the multi-model averages) period average and 1986-2005. is large in which relative 90 % at to the internal least natural of models variability agree (meaning onthan thetwo greater sign of change. standard the20 Inover deviations rainfall trend maps, years averages) the lines and in which represent 90 % at the least of models sectors agree for on the which sign averages of change. In the rainfallmodeled were the the trend maps,for period 1986-2005. lines represent the sectors for which averages were modeled for the period 1986-2005. 95 CLIMATE CHANGE ANALYSIS PERFORMED IN THE FRAWORK OF yield and reduced crop yield, surge of bush fires, silting up of river beds, losses of crops and livestock, infrastructure destruction related to floods NATIONAL ADAPTATION PLAN FOR CLIMATE or even landslides due to sudden and violent rain. CHANGE IN GUINEA VULNERABILITY OF THE RESOURCE AND OF SOCIO-ECONO- IDENTIFIED CLIMATE TREND FOR 2100 MIC GROUPS The flow of all transboundary rivers with a source in Fouta Djallon or From the perspective of water resources related to the Fouta Djallon Guinea are and will always be particularly sensitive to climate change highland, existing projections place the flow rate loss in the Konkouré in Guinea. The NAPA (National Adaptation Action Plan), developed in river at the Télimélé station at 30% and, in the most worst case scena- 2005, summarises the understanding and predicted consequences of rio, at 54% by 2100. These trends in river flows are generally expec- climate change. The presented projections for 2100 in this document ted for Guinea with flow reduction percentages that could reach 72% indicate (figure 41), a temperature increase between 0.5 °C and 4.8 °C north of the 10th parallel (case of the Milo River in Kankan). Farmers in the part of Guinea north of the 10th parallel (Central Guinea - Fou- are the most vulnerable socio-economic group in Central Guinea and ta Djallon- and Upper Guinea). South of the 10th parallel (Maritime the Fouta Djallon. Then come the gardeners and planters, whereas the Guinea and Guinea Forest Region), projected temperature increases quarry operators, merchants/transporters, small ruminant pastoralists are set between 0.4 °C and 3.9 °C by 2100. With regard to rainfall, and poultry farmers rank among the least vulnerable. The drought re- changes in the distribution and volume of precipitation are expected. mains the phenomenon which will most impact socio-economic groups In the natural region of Central Guinea, which is the region of the Fouta in Central Guinea and in the Fouta Djallon. Next come high insolation, Djallon highland, the reduction in rainfall would be between -2.8% rainfall disruption, thunderstorm activity and floods. and -26% by 2100. This reduction in rainfall would be between -4.3% and -40% in Upper Guinea, between -1.5% and -15% in Maritime ADAPTATION OPTIONS FOR CLIMATE Guinea, and between -1.8% and -17.3% in the Guinea Forest Region. CHANGE SUGGESTED BY THE NAPA From a global perspective, the regions located to the northwest and to the northeast of Guinea (above the 10th parallel) will experience a According to the Poverty Reduction Strategy Paper in Guinea, pover- 31% decrease in rainfall compared to the current average, starting in ty is more pronounced in rural areas where most of the populations 2050. This decrease could continue, to eventually reach a maximum live and carry out activities that provide them with most of their means of 40% by 2100. The regions located south of the 10th parallel north of subsistence. Several adaptation options are suggested by the NAPA should show a deficit of 7.4% in 2050, to reach a maximum of 15% in according to natural region, resource, and socio-economic group. Si- 2100. milarities with some regional options and greater relevance for some of these options (ability to ensure adaptation, coherence with strategic RISKS AND CONSEQUENCES RELATED TO CLIMATE CHANGE plans, or even local conditions for execution) have helped to select The main risks associated with the Fouta Djallon highland and identified ten main options (Table 7). Based on these options, twenty-five pro- as part of the project are drought, strong sun exposure (particularly in ject profiles organized according to climate vulnerability and areas the regions of Koundara and Gaoual and in the plains of Upper Guinea of poverty have been suggested within the framework of the NAPA towards Dinguiraye and Siguiri), the risk of flooding in the prefecture (Table 7). If part of the project profiles more specifically concerns the of Gaoual, the effect on rainfall and increased intensity of stormy rainfall coastal area (initiation of populations to oyster farming techniques, the encouraging poor infiltration and rapid discharge of water. These effects protection of seaside crop areas or even the production of spawning are expected to be felt over all Guinea with, in addition, a risk of surface grounds in estuaries), other project profiles more specifically concern temperature increase at sea level for Maritime Guinea. These risks are ex- the Fouta Djallon highland. This is true in particular for project profiles pected to have multiple consequences, which touch upon all aspects re- based on anti-erosion practices, the promotion of wire fences and li- lated to water and all socio-economic aspects. Among the most emble- ving hedges, the popularization of impluvia (rainwater collection tech- matic consequences, we will specifically note rivers and ponds drying nique for domestic use) or even the support for the development of up (major resources in the Fouta Djallon), prolonged low-water periods community plantation. for large rivers, social conflicts related to water shortages, declining soil women carrying water FOUTA DJALLON HIGHLAND WATER ATLAS • WATER CHALLENGES IN THE FOUTA DJALLON HIGHLAND Table 7 > Climate change mitigation options et project profiles in Guinea and Fouta Djallon highland (NAPA) OPTION PROJECT PROFILES IDENTIFIED BY THE NAPA IN GUINEA BUSINESS SECTOR CONCERNED CONCERNS THE FOUTA DJALLON 1. Support for the development of community and private cashew plantations Forestry YES Promotion of agroforestry 2. Support to the implementation of management plans for community forests Forestry NO Use of positive endogenous 1. Use of positive endogenous knowledge and practices Cross-sectoral YES knowledge and practices 1. Initiation of coastal populations to mangrove oyster farming techniques Coastal area NO 2. Promotion of solar energy use to extract sea salt Coastal area NO 3. Popularization of anti-erosion structures for soil protection Agriculture/Livestock farming YES Promotion of appropriate 4. Intensification of bulrush millet cultivation in the northern part of Guinea Agriculture/Livestock farming YES technologies in terms 5. Development of an early warning system for securing agricultural productivity Agriculture/Livestock farming YES of adaptation 6. Promotion of solar-powered fish dryers to reduce pressure on the mangrove Forestry NO 7. Promotion of compressed earth blocks (CEB) to reduce Forestry YES the environmental impacts of fired bricks 8. Promotion of wire fences and living hedges in Central Guinea Forestry YES Promotion of fire management 1. Promotion of fire management and deferred grazing Forestry YES and deferred grazing Protection and restoration 1. Protection of seaside crop areas Coastal area NO of fragile ecosystems 1. Dissemination of MEAs and national legal texts pertaining to Information, education Cross-sectoral NO the protection and sustainable use of natural resources and communication 2. Promotion of environmental education for coastal communities Cross-sectoral NO 1. Creation of micro-dams with multiple purposes Water resources YES Promotion of the development 2. Creation of hillside impoundments Water resources YES and integrated management 3. Creation of improved wells Water resources YES of small hydraulic structures 4. Surface water purification using Hydropur Water resources NO 5. Popularization of impluvia Water resources YES Protection of spawning grounds 1. Protection of spawning grounds in the Fatala, Konkouré and Méllacoré estuaries Coastal area NO Hydro-agricultural development 1. Development of irrigated rice-growing in Central and Upper Guinea Agriculture/Livestock farming YES of plains and lowlands 1. Promotion of small ruminant pastoralism Agriculture/Livestock farming YES Promotion of income- 2. Promotion of vegetable crops Agriculture/Livestock farming YES generating activities 3. Creation of grasscutter ranches to reduce bush fires and Agriculture/Livestock farming NO improve the living conditions of rural populations 97 CONFLICTS LINKED TO WATER (From NIASSE & BARRY) WATER-RELATED CONFLICTS ARE ESSENTIALLY LOCAL IN THE FOUTA DJALLON HIGHLAND, AND THEY ARE LINKED TO DIFFICULT ACCESS TO SAFE WATER AS WELL AS TO DISPLACEMENT DURING THE CONSTRUCTION OF HYDRAULIC STRUCTURES. THERE ARE NO INTERNATIONAL CONFLICTS STEMMING FROM WATER COMING OUT OF THE FOUTA DJALLON HIGHLAND. When dealing with water-related conflicts and the transboundary It seems that the populations displaced during the construction of can arise regarding the amount to be paid and disputes which can aspect, there is no real summary of water-related conflicts in the Garafiri facility did not benefit from a satisfactory relocation. sometimes turn violent. Finally, water pollution linked to industrial ac- Guinea and even less for the Fouta Djallon highland. In addition, There are also conflicts between urban and rural populations when tivities, notably mining-related, are also sources of tension between a conflict only arises when a claim leads to a dispute. Before this it involves waiting for a minimum quantity of water from a well. Ge- the public and operators, with the former criticising the latter for moment, there is only the risk of conflict. A university study by the nerally these populations are women and vulnerable children and not putting into place resources to limit pollution which affects other establishment 2iE (Barry, 2011) attempts to create a map of water- poor organisation or frustration can sometimes cause violent alter- activities and the health of local populations. This overview of local related conflicts or rather types of conflicts which exist, have existed cations. Conflicts between farmers and livestock breeders are also conflicts in Guinea reflects local conflicts observed in West Africa in or which could exist in Guinea. Whilst these conflicts could be noted in Guinea, especially those sharing the same resource (rivers general. These conflicts arise when the resource is difficult for the major and lead to negotiations at a national level, most of conflicts and shorelines) used for market gardening in the low levels and population to access, when facilities damage cultural or historic prac- arise at a much more local level, without being any less damaging watering. Destruction of crops on the one hand and a lack of clear tices or when arbitration is not clearly established for sharing access for the affected populations. marking-out of the grazing area on the other cause tension which to water resources. can end in violence. Barry mentions that for this type of conflict, and OVERVIEW OF LOCAL AND INTERNAL in certain Fouta Djallon regions, a prior discussion is held between CONFLICTS TO GUINEA those involved in order to jointly define the crop and grazing areas. There are sometimes conflicts linked to water billing between users At the first level of local conflicts, hydroelectric power facilities have and water management companies. Faced with the scarcity, distance a significant position, notably when moving and then rehousing local travelled to get the water or fluctuations in the water supply, tensions communities where the sites can have significant cultural importance. Watering livestock in river Cultures with fence in the Fouta Djallon highland FOUTA DJALLON HIGHLAND WATER ATLAS • WATER CHALLENGES IN THE FOUTA DJALLON HIGHLAND COMMON FEATURES OF WATER TRANSBOUNDARY BASIN ORGANISATIONS TRANSBOUNDARY CONFLICTS IN WEST AS MODERATORS OF REGIONAL WATER AFRICA CONFLICTS? In addition to local conflicts, there are also transboundary conflicts. In Cooperation within a transboundary basin organisation (CBO) its work to prevent conflicts and on cooperation in managing West does not exclude conflicts between countries. In the Senegal basin, African transboundary river water, Niassa lists the risks of transboun- between 1987 and 1989, the construction of the Manantali facility dary conflicts which have existed (Senegal and Maurtania in 1988 deepened social inequalities by not totally responding to commit- - next chapter; Ghana and Burkina Faso in 1998, Benin and Niger ments made. The priority given to hydroelectric power production since the 1960s; Nigeria and Niger in 2002, Cameroon and Nigeria over flood recession cultivation and irrigated cultivation has notably between 1980 and 2002) and makes general observations on the created a land open to tension by making households unable to culti- risks of conflict. Therefore, many are linked to the modification of flow vate their land, causing a wave of emigration and proletarianization in regimes caused by hydroelectric power facilities. On the one hand, the valley. The gap is therefore deepened between disadvantaged Niassa notes that the construction of water control facilities pushes farmers and those who, with resources, were able to benefit from the local governments to “mark their territory” by trying to control the facility. In this vein, tensions and quarrels between opposing Sene- largest possible portion of the land in question. Therefore it notes galese farmers and Mauritanian shepherds rose and caused a diplo- that the lack of control by populations of new challenges caused by matic freeze between Senegal and Mauritania for three years. During major hydro-agricultural facilities leads the latter to maintain their this period when Senegal and Mauritania would only speak through traditional practices (migration or agriculture) when there is a deep intermediaries, the OMVS continued to operate, acting as a com- Laundry in river upset in progress (reducing the flows of certain periods and increase munication agent between both countries, and it played the same of others, scarcity on one side and opulence on the other...). Finally, role in progressively easing tensions between the country (Alam the impacts experienced or expected from dams are also sources of et al., 2009: 94 ; Green Cross, 2000 : 57 ; Niasse, 2004 : 7). Other tension between local communities (notably downstream from the tensions have arisen between Senegal and Mauritania, especially on ABN - “Any dispute arising between member states in the interpretation or application of this agreement is governed facilities) which can be alarmed very early on due to a fall in flow the project to revitalise fossil valleys and each time the OMVS has amicably through direct negotiations. Failing that, the dis- or a change in water quality when the facility is not yet constructed. acted as an “arbitrator”. It should be noted that this area of conflict pute is taken by one of the parties to the Summit (of Heads Nevertheless, in West Africa there is no major transboundary conflict prevention is a key part of CBO concerns which, like the ABN and of State and Government) who rule as a last resort. “ Source: directly linked to water (Niassa 2014). For the Fouta Djallon, des- OMVS, have procedures in place regarding the settlement of inter- Reviewed convention creating the Niger Basin Authority pite Guinea’s distancing from transboundary institutions, and even national water-related disputes. Niasse notably suggests reinforcing (Faranah, October 1987), article 20. though tensions have been felt, no conflict has arisen between Gui- this function of “regulation, prevention and management of conflicts nea and its neighbours. Since 2006, Guinea joined the OMVS and by transboundary basin organisations” by implementing information OMVS - “If there is no deal between the countries, any OMVG and large-scale development projects (Kokoutamba, Fomi, sharing systems, implementing a code of conduct between member dispute which arises between them regarding the interpre- Kaléta dams, etc.) which are beneficial for Guinea and the sub-region states (foundation in water charters) or even the development of a tation or application of this convention will be resolved which are starting to operate in a collaborative environment where ECOWAS regional directive on shared water management. through conciliation or mediation. If there is no agreement, water leads to cooperation rather than conflict. the contractor countries must submit to the Organisation of African Unity’s arbitration and conciliation committee. As a last resort, they will submit it to the International Court of Justice in the Hague”. Source: Convention relating to the Se- negal river status (11 March 1972), article 18. 99 THE FOUTA DJALLON HIGHLAND’S GOUVERNANCE THE RPID-FDH ORIGINATED IN THE 1980S TO FIGHT AGAINST DROUGHT AND DESERTIFICATION. FOLLOWING LOCAL ACTIONS ON PILOT SITES, IT HAS EXPANDED ITS EFFORTS THROUGH THE CREATION OF NATIONAL PARKS AND FOREST RESERVES IN GUINEA AND ITS BORDER AREAS. THE FOUTA DJALLON HIGHLAND LIE AT THE CROSSROADS BETWEEN THREE TRANSBOUNDARY BASIN ORGANIZATIONS AND ECOWAS-WRCC PROMOTES COORDINATION FOR A REAL INTEGRATED MANAGEMENT OF WATER RESOURCES WITHIN THE FOUTA DJALLON HIGHLAND AND THE ONES ORIGINATING IN THEM. THE FOUTA DJALLON HIGHLAND REGIONAL • The decision- and policy-making bodies are: (I) the Summit of Heads the Fouta Djallon highland by the 5thMinisterial Conference of the of State and Government; (ii) the Ministerial Conference. RPID-FDH, held in Freetown (Sierra Leone) in November 2011; INTEGRATED DEVELOPMENT PROGRAMM • The advisory and monitoring-evaluation bodies are: (I) the Regional The ratification by several Member States of said Framework • HISTORY AND OPERATING ENVIRONMENT Advisory Committee; (ii) the Scientific and Technical Committee. Convention; The international community recognized the need for a regional ap- • The implementing bodies are: (I) the Office for International Coordi- • The initiation of documents available for the Observatory, along with proach to the integrated development of the FDH during the Interna- nation; (ii) the National Coordination and Monitoring Bodies. an action plan for the Observatory; tional Conference on Soil, held in Dalaba (Guinea) in 1959. However, • Monitoring and management Indicators; It must be emphasized that Summit of Heads of State and Government it is only in the beginning of the 1970s, in the aftermath of the Sahel of the RPID-FDH has never met to date, and that the Scientific and • A data collection network; drought, that, during the thirty-third sessions of the Council of Minis- Technical Committee is not operational as yet. Among the achieve- • The construction of premises for the Observatory at the OIC-AU; ters of the Organization of African Unity (OAU), held in Monrovia ments of the RPID-FDH, the following can be specifically noted: (Liberia), the decision was made to carry out a concerted action un- • The development of the draft document for the Cooperation der the aegis of the OAU. The OAU, in partnership with UNEP, FAO, • The production of numerous studies on the FDH; Convention with Basin Organizations; UNESCO and UNSO, has therefore implemented the Regional Pro- • A variety of activities on pilot sites; • The INRM (integrated natural resources management) project of the gram for the Integrated Development of the Fouta Djallon highland • The development and signature of the Framework Convention of FDH (RPID-FDH) at the beginning of the 1990s. The RPID-FDH concerns cooperation between the riparian States of the rivers originating in eight countries dependent upon the waters of the Highlands: The Gambia, Guinea, Guinea Bissau, Mali, Mauritania, Niger, Senegal and Sierra Leone. Longtime observers, Benin and Nigeria, riparian coun- tries of the Niger River, are about to become full members of the bo- dies of the RPID-FDH. The objective of the RPID-FDH is «to ensure the protection and rational use of natural resources in the FDH in order to contribute to the improvement of living standards for the population of the highland». It is implemented by the AU Commission, through the Office for International Coordination of the African Union (OIC- AU). The influences of the RPID-FDH project have been divided into two sectors. A project sector focused on Guinea and a wider sector which integrates the 7 other countries (Map 42). The fundamental components of the RPID-FDH are: • Sub-regional cooperation • Sustainable management of natural resources and improvement of living conditions • Adaptation and mitigation of risks related to climate change • Coordination of regional and national efforts and capacity building The institutional framework of the RPID-FDH consists of decision- and policy-making bodies, advisory and monitoring-evaluation bodies, and implementing bodies. Panel of RPID FDH in a pilot site FOUTA DJALLON HIGHLAND WATER ATLAS • WATER CHALLENGES IN THE FOUTA DJALLON HIGHLAND Delineation of RPID Map 42 > Geographical shapeFouta of Fouta Djallon highland Djallon highland and RPID project location and location ofof pilot sites sites of the project pilot -15.0 Saint Louis M A U R I T A N I A -10.0 Hodh Ech Chargui Gorgol Assaba Hodh El Gharbi Louga Guidimaka Matam 15.0 Thies Diourbel S E N E G A L Mopti DAKAR Fatick Ka rine Kaolack Segou Tambacounda Kayes Central River North Bank T H E G A M B I A Koulikoro Banjul Upper River M A L I Western Kolda Sedhiou Kedougou Ziguinchor G U I N E A BAMAKO Cacheu Oio I S S A U B Bafata Gabu BISSAU Biombo Quinara Labe A Boke Tombali Sikasso T G U I N E A L A Mamou Kankan Faranah N T Kindia I 10.0 C O CONAKRY Pilot sites of RPID FDH C E Northern A N S I E R R A I V O R Y Legend L E O N E FREETOWN N'Zerekore C O A S T Guinean prefecture associated to RPID FDH (15) Western Area Eastern Guinean prefectures partially associated to RPID FDH (7) Southern Guinean prefectures unconcerned by RPID FDH Restricted extension zone L I B E R I A Wider extension zone -10.0 Projection latitude - longitude WGS 84 - Géohyd - FAO - RPID FDH - Created by Géohyd Anteagroup - Axel Aurouet 2017 101 GOUVERNANCE VARIABLES ACTIONS DURING TIME jects through the so-called “Pilot Representative Basin (BRP)” basin INITIATIVE TO TRANSFER THE RESPONSIBILITY OF THE RPID- development approach (Map 4). The main activities carried out on FDH FROM THE AFRICAN UNION TO ECOWAS The first step (1981-1987) involved implementing infrastructures and these pilot sites are : The principle of ultimately transferring the responsibility for the pro- working structures including the Fouta Djallon highland Integrated Development and Restoration Service (FDH/IDRS) and, on the other • The technical supervision of groups for gardening and compost gram to ECOWAS was enshrined from the onset in the conceptual hand, establishing a diagnosis on the causes of the deterioration of techniques, and support for equipment and seeds in Guelin; logic of the RPID-FDH. It is based on the principle of subsidiarity, natural resources, identification of 12 river basins followed by the • Introduction of a rice huller; which is one of the action principles of both the AU and ECOWAS. development of an intervention strategy to regularise the shared ri- Thus, based on the fact that the Fouta Djallon highland, which is enti- • Training of group leaders in sound governance and community ver regime and improve living conditions for local communities. The rely located in West Africa, is first and foremost a heritage landmark life; second step (1988-1998) involved implementing experimental pro- of this region, the 73rd Ordinary Session of the OAU Council of • Planting of forest trees and fruit trees in 2012, 2013 and 2014 over Ministers approved «the principle of a transfer of responsibility» an 8 ha surface area in Guelin; for the RPID-FDH to ECOWAS and therefore committed the OAU’s • Equipment support for the private nurseryman of the pilot site; General Secretariat to carry out consultations with the Executive Se- • Allocation of firefighting equipment for the firefighting committee; cretariat of ECOWAS in order to set its modalities (Decision CM/ DEC LXXXIII). • Development of 6.52 ha of lowlands with a submersion irrigation system and a 26.94 ha barbed wire fence and slopes landscaped And it is by referring to this decision, later confirmed by the 3rd Or- with vetiver plants and deferred grazing; dinary Session of the Council of Ministers of the African Union (AU) • Planting of a living hedge in Guelin; held in July 2003 in Maputo (Mozambique), that the AU’s Commis- sioner for Rural Economy and Agriculture requested the ECOWAS • Delivery of oxen, harrows and plows to the Tolo center and to Commission’s Chairman to implement the decision above, in an Guelin, and training in animal traction; official letter dated April 16, 2013. A process to transfer responsi- • An experience sharing trip with farmers who are leaders in lives- bility for the RPID-FDH from the AU to ECOWAS, started in 2014, tock farming, gardening and forestry; is currently at an advanced stage. The adopted roadmap revolves • Awareness-raising for the stakeholders and partners with regard to around key activities: fighting bush fires; • Planting of 170 fruit trees in 2014; • To formalize transfer of the program’s responsibility from the AU • Installing 2 information panels for the pilot site. to ECOWAS; Success in these activities has taken the form, inter alia, of reduced • To develop a Five-Year Investment Plan (FYIP) for the Fouta Djallon conflicts between farmers and livestock breeders with the use of highland; fences, the progressive phasing-out of mountain slopes to start work in developed lowlands - thus limiting logging - agricultural produc- • To organize an information and advocacy campaign to preserve tion not limited to the rainy season, reduced numbers of bush fires and sustainably manage the Fouta Djallon highland. due to awareness-raising and firefighting equipment provided, im- In parallel with the responsibility transfer process for the RPID- provement of revenue, or even areas opening up due to the deve- FDH, ECOWAS, through its Water Resources Coordination Center lopment of lowlands. Nonetheless, the activities carried out do not (WRCC), is currently conducting operational activities in the field. yet affect all pilot sites, and these activities should be continued and These activities essentially focus on the development of this water expanded in the future. atlas, thus aiming to widely share knowledge on the Fouta Djallon, The regional programme was extended to create and manage two and on the implementation of a partnership platform between Basin national parks (the Badiar Park in Central Guinea and Mafou park in Organizations and ECOWAS to preserve and sustainably manage Upper Guinea -map 40) and two transboundary protected areas the Fouta Djallon highland. (Guinea - Guinea Bissau and Guinea - Mali). An assessment of these projects, carried out in 1998, highlighted a good number of positive results but also noted weaknesses, the lack of relevant indicators for monitoring, assessment and analysis of the impact and lack of an ap- propriate framework between the different parties involved. View on a RPID FDH pilot site FOUTA DJALLON HIGHLAND WATER ATLAS • WATER CHALLENGES IN THE FOUTA DJALLON HIGHLAND ECOWAS countries Map43 > Countries and transboundary and transboundary basin basin organization authority of ECOWAS region -20.0 -10.0 0.0 10.0 EC Libya OW Algeria AS AR EA Mauritania 20.0 Mali OMVS Niger LCBC Senegal NBA Chad The Gambia OMVG Burkina Faso A Guinea- Bissau T Guinea L VBA 10.0 A Topographic highland Benin Nigeria N of Coastal Guinea Sierra Leone T Togo Ghana Topographic highland C I of Fouta Djallon Ivory Coast Liberia O Central African Topographic highland C Republic of Guinean Dorsal E Cameroon A G U I N N EA Legend N NBA: Niger Basin Authority VBA: Volta Basin Authority ICCOS G Equatorial LCBC : Lake Chad Basin Commission UL Guinea ICCOS : International Commission of Congo-Oubangui-Sangha basin Congo Republic OMVG : Organization for the development of Gambia river Gabon F OMVS : Organization for the development of Senegal river Projection latitude - longitude WGS 84 - Géohyd - topographic highland from L. ferry, 2017 - Created by Géohyd Anteagroup - Luc Ferry & Axel Aurouet 2017 0.0 103 GOUVERNANCE WATER GOVERNANCE IN THE FOUTA DJAL- bodies for the participation of users, each according to their own ECOWAS-WRCC regularly presents the IWRM situation and pro- legislation. The following are also involved in the FDH: gress in member countries. This exercise took place in 2003, 2005, LON AND ITS EXTENDED AREAS 2007 and 2012. The tables below present the latest known situa- • For the NBA, the «National Coordination» for Guinea and the lo- INTEGRATED WATER RESOURCES MANAGEMENT FRAMEWORK cal bodies of the GIRENS program (Integrated Water Resources tion in December 2012. The table 9 deals with the three key fields: Management for Upper Niger); politics, legal and institutional. The table 8 presents the progress of By adopting the “Ouagadougou Declaration” in March 1998, the planning instruments: IWRM road maps and IWRM action plans. West African countries are firmly committed to a national process to • For the OMVG, the «National Monitoring Committee» and the transition towards integrated water resources management (IWRM). Figure 43 > The countries of the Fouta Djallon highland «Local Coordination and Monitoring Committees»; and Working on the transition towards the IWRM involves moving from and the TBO they have set up • For the OMVS, the «Local Coordination Committees» of Mamou, sector-based water management - with the inherent faults linked to FOUTA DJALLON Tougué, Mali and Siguiri. this type of management - to integrated management based on the HIGHLANDS ABN OMVG OMVS MRU* principles adopted during the water and development conference The TBOs of the Highlands have been particularly active in the pro- COUNTRIES AND tection/restoration of the heads of the sources of their respective TBOS SET UP in Dublin, January 1992 (figure 42). basins, involving local populations in the process. THE GAMBIA GUINEA «TRADITIONAL» WATER RESOURCES MANAGEMENT «INTEGRATED» WATER RESOURCES MANAGEMENT GUINEA-BISSAU • Sectoral • Trans-sectoral MALI • Not taking the environment into account • Taking environmental imperatives into account MAURITANIA • Technocratic IWRM • Participatory • Male-dominated TRANSITION • Mindful of «gender» aspects NIGER • Centralized PROCESS • Decentralized SENEGAL • Opaque • Obligation to provide information • Source of conflict • Consensual SIERRA LEONE • Supply-based • Demand-driven • By administrative entities • By bodies of water (basins, aquifers, lakes) * The Mano River Union is a political organisation for development that develop the setting up of an integrated water resources management framework along the Figure 42 > Transition process to IWRM according to Dublin Conference on Water and Development 1992 international river, Mano-morro. In the Fouta Djallon highland, water resource management is the responsibility of the eight tributary countries affected by national Table 8 > Planning tools situation and their state of implementation at end of 2012 issues, and the CBO transboundary basin organisations regarding PHASE 2 PLANNING PHASE 3 IMPLEMENTATION international issues (map 43 and figure 43). Local communities in COUNTRY PHASE 1 IMPLEMENTATION OF THE ROADMAP IWRM ACTION PLAN ACTION PLAN the Republic of Guinea (urban communities and developing rural communities), located in all or a part of the FDH, are governed by THE GAMBIA Completed Completed 2009 To be initiated n.a. the Local Government Code of 2006. According to this Code (still GUINEA Completed Completed 2011 To be initiated n.a. in force until the promulgation of the Revised Code adopted by the National Assembly in February 2017), municipalities are com- GUINEA-BISSAU Completed Completed 2009 To be initiated n.a. petent in terms of the «management of water and water points». MAURITANIA Was not part of the 2012 survey They can set up and manage any public service within their areas MALI Completed n.a. Completed 2008 In progress of competence on their territory. Local public services include, in particular, «the distribution of drinking water». In addition to this NIGER Completed n.a. Startup planned for 2013 n.a. system, through its water resource coordination centre (WRCC), the SENEGAL Completed Completed Completed 2007 In progress ECOWAS promotes and coordinates the transition to the IWRM. Mauritania left ECOWAS in 2000 but plans to rejoin. SIERRA LEONE Completed Completed To be initiated n.a. The OMVS adopted its Water Charter in 2002 and the NBA adop- ECOWAS REGION Completed n.a. Completed 2000 In progress ted its Water Charter in 2008. The three TBOs of the Fouta Djal- Countries having benefited from support: From the ACP-EU / UNEP project to support From the ACDI-GWP project to support lon highland (NBA, OMVG, OMVS) have implemented national IWRM IWRM FOUTA DJALLON HIGHLAND WATER ATLAS • WATER CHALLENGES IN THE FOUTA DJALLON HIGHLAND Table 9 > State of the water management framework at end of 2012 POLITICAL LEGAL INSTITUTIONAL Is there a cross-sectorial executive body responsible Is there a National or a Regional Water Partnership? Is there a Code, or specific laws, related to water? Application of the "Polluter Pays" principle (PPP)? Is there an inter-ministerial coordination body? Application of the "User Pays" principle (UPP)? Participation of stakeholders in management? Is there a particular role for women planned? Is this document based on IWRM principles? If so, does implementation regulation exist? Is the national legal framework harmonized Is there a national water policy document? Application of the subsidiarity principle? Are there basin management bodies? Is there a national advisory authority? What is the legal status of water? with international agreements? Is the private sector involved Management by river basin? with water management? for IWRM? COUNTRY THE 2007 • C 1979 o • • • • • • • o • • • n.a. 2011 GAMBIA GUINEA -> • S 1994 o • • -> -> -> X X o • X • •3 2006 GUINEA- 1992 o S -> n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. X • • -> 2011 BISSAU MALI 2006 • S 2002 o • • • • o • • o • • • •2 2003 NIGER 2000 • V 2010 o • • • • • • • • • • • 7* 2006 SENEGAL 2005 o S 1981 o • • • • • • • • • • • •1 2002 SIERRA 1961 2010 • V o • o X X X o X o • • -> F 2012 LEONE 2004 CEDEAO 2008 • n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. n.a. • • • •5 2002 (régional) Table legend: Status of water Note • Yes / exists (2000: exists since the date indicated) C: common property * In Niger, geographically delineated water management units (WMU) o Partly exists S: property of the State have been set up, but they are not strictly speaking basin organizations. -> Currently being drafted or created P: private property F Expected in the future V: variable status as the case may be X No or does not exist n.a. = not applicable 105 SUMMARY OF THE ISSUES Climate change and its consequences are a major issue for the Fouta Djallon highland. The wa- Highlands play an important role in their prevention. It is also important to note that Guinea is ter resources’ marked dependence upon rainfall exacerbates the variable character of the wa- part of the ECOWAS Directive on the development of hydraulic infrastructure in West Africa, terways’ flow rates. The effects of the worsening of climatic conditions (prolonged drought) of adopted in June 2017 in Monrovia, Sierra Leone. This directive contains recommendations the 1970s are still very present in the minds, and rainfall levels of the past 20 years have not which tend to maximize the advantages of the structures, and to anticipate in order to mini- caught up with those observed from the beginning to the middle of the 20th century. The IPCC’s mize the negative impacts of large dams. rainfall forecasts vary according to the predictive models selected and do not allow for the iden- tification of converging trends for West Africa: some predict more rains, others less. However, as In general, the Fouta Djallon highland is a strategic space, the significance of which has long indicated in the National Action Plan on climate change adaptation in Guinea, warming is likely been identified. The Regional Program for the Integrated Development of the Fouta Djallon certain, and it will be between 0.3 and 2.2 °C. This holds true also for the modification in rainfall highland (RPID-FDH) was a 1981 initiative from the Organization of African Unity related to distribution and its unpredictability. For this reason, several adaptation projects are identified desertification and drought issues. Currently, actions to fight against bush fires, to limit land in the area of the Fouta Djallon highland, the most emblematic of which for water resources clearing or to develop land are carried out on pilot sites and the Program has been extended and agriculture concerns are the drilling of improved wells, the popularization of impluvia, the to create 2 national parks in Guinea and 2 protected areas. popularization of anti-erosion practices, the development of early warning systems for securing Lastly, the Fouta Djallon is a space that is rich in biodiversity, and fauna includes leopards, mon- agricultural production or even the promotion of positive endogenous practices. keys, hippos, baboons and chimpanzees. Chimpanzee populations are among the largest in Water can be a source of conflict on a local or an international scale. With regard to the Fouta West Africa (17,700 individuals). The Fouta Djallon harbors almost 64 forest reserves and it has Djallon, which is the origin of many transboundary rivers, the conflicts identified are more local recently seen the creation of the Bafing National Park between its source and its outlet from in nature. These are most often the result of population displacement caused by large hydrau- Guinea. However, this great resource remains fragile in the face of human activities and climate lic structures or even by poor access to safe drinking water. There are no identified conflicts on challenges. This is why a rich biodiversity is a factor taken into account for all development an international scale related to the water resources of the Fouta Djallon. By promoting coo- reflections and projects. peration and the exchange of information, the various basin organizations concerned by the FOUTA DJALLON HIGHLAND WATER ATLAS • WATER CHALLENGES IN THE FOUTA DJALLON HIGHLAND Fonio field in Guinea 107 CONCLUSIONS OF THE ATLAS The water atlas for the Fouta Djallon highland This atlas highlights the abundance of surface water This document also features the main socio-econo- highlights the plurality of the Highlands’ definitions resources in the Fouta Djallon highland to the detri- mic activities in the Fouta Djallon and its extensions. in the literature dedicated to them. The definition ment of groundwater resources. The latter, very loca- Despite a diversified agricultural sector and signifi- of the Fouta Djallon highland provided in this atlas lized and not generalized throughout the Highlands, cant mining resources, the area of the Fouta Djallon must be understood in the light of the definition of are dwindling fast and cannot provide a lasting re- highland is dominated by hydroelectric develop- other neighboring highlands, especially the Guinean source during the entire year. Thus, waterways consti- ment. The multiplicity of recent or planned pro- Highlands and the coastal Guinea mountains which tute a considerable resource, but one that remains jects (Kaléta structure with an interconnection with also play a significant role in the dynamics of water fragile in the face of climate-related drought or rain- Sambangalou, Souapiti structure, Félou structure, resources in this area and in the West African sub-re- fall deficit. It seems essential to continue the effort to Gouina, etc.) confirms the significant hydroelectric gion. One of the added singular values of the atlas is acquire hydro-morphological knowledge in order to potential offered by the highland. The positive that it makes it possible to grasp the segmentation of better plan and manage water resources, in addition socio-economic consequences expected of these watersheds and the highlands to which they belong. to the actions led on a wider scale in the main West projects are real. Nevertheless, vigilance is called African watersheds concerned by the Highlands: for to limit and mitigate the sometimes negative Gambia, Senegal and Niger. Improving knowledge is consequences of these works on hydrological re- a challenge, especially due to the difficulty to acquire gimes, habitats, biodiversity or the quality of water. basic information related to waterways and to sustain the process using the appropriate digital tools. This challenge must be met while fully aware of the situa- tion in the countries concerned. FOUTA DJALLON HIGHLAND WATER ATLAS Although quite an exhaustive overview of the situation The water atlas represents an initial knowledge base concerning these Highlands which are important for of the Fouta Djallon has been provided throughout the sub-region. The many upcoming issues and challenges, whether they arise from climate, agriculture or these pages, there remains themes and topics which, demographics, are an invitation to continue this work with the objective to reach a balanced and sustainable because of the lack of literature or sufficient knowledge, management of water resources and natural spaces. have not been addressed thoroughly. This is particular- ly true for erosion issues in the Fouta Djallon highland, water quality, floods or even the evolution of forest cover in the highland. There is currently no institution in charge of compiling and centralizing all information pertaining to the Fouta Djallon highland and the in- formation acquisition networks (hydro-climatic, water quality, piezometry, etc.) are scattered among several institutions. These deficiencies and the fragmentation of information demonstrate the benefit provided by an «observatory» type of information system based on strengthening all information production lines, trai- ning the people concerned who are the links in this chain, and translating the whole into indicators that shed light on the issues. 109 ICONOGRAPHY MAPS 37 - Importance of mining income in countries linekd to Fouta Djallon highland - Page 85 38 - Gitology area or evidence of ore in Fouta Djallon highland and its extension zones - Page 87 1 - Natural region of Guinea - Page 10 39 - Production and share of production of fonio inside Guinean prefectures of Fouta Djallon Highland - Page 89 2 - Delineation of Fouta Djallon highland, its extension zones and surrounding topographic highlands - Page 11 40 - protected areas linked with Fouta Djallon highland and its extension zones - Page 93 3 - Main river basins of west Africa - Page 12 41 - moving of isohyets between 1951 - 1969 and 1970 - 1981 period D’après / From l’Hôte & Mahé (1995) - Page 94 4 - Area of influence of Fouta Djallon highland and Guinean Dorsal on West African rivers - Page 13 42 - Geographical shape of Fouta Djallon highland RPID project and location of pilot sites - Page 101 5 - Topographic highlands of the area and position of altimetry profiles - Page 16 43 - Countries and transboundary basin organization of ECOWAS region - Page 103 6 - Topographic highland of Fouta Djallon at 440 m above sea level - Page 18 7 - Topographic highland of Guinean Dorsal at 440 m above sea level - Page 19 FIGURES 8 - River basins linked with Fouta Djallon highland, Guinean Dorsal and Coastal Guinea Highland - Page 21 9 - Rivers and basins of south-west coastal area - Page 23 1 - Altimetry profile and drainage divided line between Fouta Djallon highland, Guinean Dorsal and highland of Ma- dinani region (Profile 1-a 1-b map 5) - Page 17 10 - Rivers and basins of Sénégal, Gambia, Geba and Corubal - Page 25 2 - Altimetry profile and drainage divided line between Fouta Djallon highland and Coastal Guinea Highland (Profile 11 - Rivers and sub-basins of upstream Niger river - Page 27 2-a 2-b map 5) - Page 17 12 - Geological context of Fouta Djallon and its extension zones - Page 29 3 - Altimetry profile and drainage divided line between Fouta Djallon highland, Siguirini-Baléa highland and manding 13 - Land cover of Fouta Djallon highland and its extension zones (Glob cover 2008) - Page 31 mounts (Profile 3-a 3-b map 5) - Page 17 14 - Morphopedological landscape of Guinea - Page 33 3bis - Altimetry profile and drainage divided line of Guinean Dorsal (Profile 4-a 4-b map 5) - Page 18 15 - Intertropical Convergence Zone (ITCZ) - Page 34 4 - Longitudinal profile of Koukoure and its main tributaries - Page 22 16 - Mean annual temperature in West Africa - Page 35 5 - Longitudinal profile of Senegal and its main tributaries - Page 24 17 - Mean annual rainfall for 1959-1981 period (from l’Hote et Mahé) - Page 39 6 - Longitudinal profile of Niger and its main tributaries - Page 26 18 - Rivers linked with Fouta Djallon highland and surrounding highlands - Page 43 7 - Land cover distribution in topographic highland of Fouta Djallon (Glob cover 2008) - Page 30 19 - Main river flow stations on Senegal river basin - Page 49 8 - Edge of lateritic plateau (from Demangeot - 1976) - Page 32 20 - Main river flow stations on upstream Niger river basin - Page 51 9 - Rainfall of «Forest Guinea» climatic domain - Page 36 21 - Main river flow stations on Gambia river basin - Page 57 10 - Rainfall of «East Guinea» climatic domain - Page 36 22 - Main river flow stations on South-west coastal river basin - Page 59 11 - Rainfall of «maritime Guinea» climatic domain - Page 37 23 - West African aquifer systems from M. Niasse & C. Mbow © Club du Sahel et de l’Afrique de l’Ouest / OECD 12 - Rainfall of «Fouta Djallon» climatic domain - Page 37 (2006) - Page 61 13 - Rainfall of «Sudanian» climatic domain - Page 38 24 - Mean internannual river flow on main rivers form Fouta Djallon and surrounding highlands - Page 63 14 - Rainfall Index at Labe Station - Page 41 25 - Topographic highlands and natural region of Guinea - Page 66 15 - Monthly mean and daily mean river flow on Bafing at Sokotoro / Period 1972 - 2016 - Page 46 26 - Natural region of Guinea and associated RPID-FDH prefectures of Guinea - Page 67 16 - Monthly mean and daily mean river flow on Bafing at Makana / Période 1960 - 2016 - Page 47 27 - Population and population density inside guinean prefectures of Fouta Djallon highland (2014) - Page 69 17 - Monthly mean and daily mean river flow on Falémé at Gourbassi / Période 1960 - 2012 - Page 47 28 - Percentage of the population with access to improved water source at national scale (2015) - Page 70 18 - Share contribution of tributaries of Senegal river at Bakel station - Page 47 29 - Population and population density in administrative regions of extension zones of Fouta Djallon highland (2014) 19 - Comparison of daily river flow before and after Manantali commossioning at Bakel station -Senegal river - Page 48 - Page 71 20 - Yearly mean river flow on Senegal at Bakel / Period 1960 - 2015 - Page 48 30 - Production and share of production of cassava inside Guinean prefectures of Fouta Djallon Highland - Page 73 21 - Monthly mean and daily mean river flow on Tinkisso at Tinkisso / Période 1955 - 2009 - Page 50 31 - Production and share of production of rice inside Guinean prefectures of Fouta Djallon Highland - Page 74 22 - Monthly mean and daily mean river flow on Niandan at Baro / Période 1948 - 1983 - Page 52 32 - Production and share of production of maize inside Guinean prefectures of Fouta Djallon Highland - Page 75 24 - Monthly mean and daily mean river flow on Sankarani at Mandiana / Période 1955 - 2006 - Page 52 33 - Cattle and Cattle density inside Guinean prefectures of Fouta Djallon Highland (2016) - Page 77 23 - Monthly mean and daily mean river flow on Milo at Kankan / Période 1940 - 2008 - Page 52 34 - Artificial lake of Manantali dam on Bafing river (Kayes region) - Page 79 25 - Hydraulicity of Niger river between 1907 and 2009 at Koulikoro station (from Luc Ferry) - Page 53 35 - Hydroelectricity facilities and hydroelectricity projects linked with Fouta Djallon highland - Page 83 26 - Monthly mean and daily mean river flow on Kakrima at Kaba / Période 1988 - 2016 - Page 54 36 - gitology or evidence of ore in heart of Fouta Djallon highland - Page 84 FOUTA DJALLON HIGHLAND WATER ATLAS 27 - Monthly mean and daily mean river flow on Konkouré at Linsan / Période 1955 - 2007 - Page 54 Christian Lévêque © IRD - Page 19 28 - Comparison of monthly mean and daily mean river flow of Konkoure at Télimélé before and after commissioning © FAO PGRIN - Pages 60, 68, 76, 98, 99, 100, 102, 109 of Garafiri dam - Page 55 © Google - Page 72 29 - Monthly mean and daily mean river flow on Kogon at Pont / Période 1957 - 2016 - Page 55 © Global Land Cover Facility - University of Maryland, College Park, USA - Page 8 30 - Monthly mean and daily mean river flow on Gambia at Kédougou / Période 1970 - 2014 - Page 56 © Pixabay - Page 92 31 - Hydraulicity of Gambia river between 1904 and 1999 at Kédougou (reconstructed from Orange and Da Costa) - Page 56 © Tractebel - Page 82 32 - Monthly mean and daily mean river flow on Tomine at Gaoual / Période 1970 - 2014 - Page 58 33 - Population of Guinea that is concerned by Fouta Djallon in 2014 - Page 68 34 - Population trend between 1983 and 2014 in Guinea and in prefecture of Fouta Djallon - Page 68 35 - Modality and rate of access to drinking water in the administrative regions of Mamou and Labé (2002) - Page 70 GLOSSARY 36 - Access to the toilet in the administrative regions of Mamou and Labé (2002) - Page 70 37 - Distribution of agricultural production in tons and by type of crop in administrative region of Labe and Mamou in AU African Union 2000 - 2001 - Page 72 ECOWAS Economic Community of West African States 38 - Number of cattle, sheep, goats and pigs in the Guinean prefectures of the Fouta Djallon highland (2016) - Page 76 FAO Food and Agriculture Organization 39 - Contribution of the prefectures of Guinea in the total use of pesticides in Guinea - Page 78 FDH Fouta Djallon Highland 40 - Hydroelectric potential, exploitation and exploitation project linked with Fouta Djallon highland - Page 81 GLC Global Land Cover 41 - Predicting Climate Change in Sub-Saharan Africa and North Africa by 2100 - IPCC 2013 - Page 95 IPCC Intergovernmental Panel on Climate Change 42 - Transition process to IWRM according to Dublin Conference on Water and Development 1992 - Page 104 IRD French Research Institute for Development 43 - The countries of the Fouta Djallon highland and the TBO they have set up - Page 104 IUCN International Union for Conservation of Nature IWRM Integrated Water Resource Management TABLES LCBC Lake Chad Basin committee MBA Mono Basin Authority 1 - Main characteristics of highlands - Page 16 MRU Mano River Union 2 - Main characteristics of river basins - Page 20 NBA Niger Basin Authority 3 - lithological characteristics of few sub-basins - Page 28 NAPA National Action Plan for Adaptation 4 - Trend of mean thirty-years rainfall in West Africa between 1931 and 2000 ( JC Bader) - Page 40 OAU Organization of African Unity 5 - Hydraulicity periods of Niger river at Koulikoro station between 1907 and 2010 (from Luc Ferry) - Page 53 OECD Organization for Economic Co-operation and Development 6 - Main hydroelectricity facilities in Guinea (2016) - Page 80 OMVG Organization for the Development of Gambia River 7 - Climate change mitigation options et project profiles in Guinea and Fouta Djallon highland (NAPA) - Page 97 OMVS Organization for the Development of Senegal River 8 - Planning tools situation and their state of implementation at end of 2012 - Page 104 PET Potential evapotranspiration 9 - State of the water management framework at end of 2012 - Page 105 RET Real evapotranspiration RPID-FDG Regional Program for the integrated Development of the Fouta Djallon Highlands TBO Transboundary Basin Organization PHOTOGRAPHS UNDP United Nations Development Program UNEP United Nations Environment Program Axel Aurouet © Géohyd - Anteagroup - Pages 12, 14, 22, 35, 37, 38, 44, 53, 55, 58, 66, 78, 82, 90, 96, 102 UNESCO United Nations Educational, Scientific and Cultural Organization Adeline Barnaud © IRD - Pages 64, 106 VBA Volta Basin Authority Yves Boulvert © IRD - Pages 30, 41 WHO World Health Organization Michel Durkhan © IRD - Page 47 WRCC Water Resource Coordination Center of ECOWAS Luc Ferry © IRD - Page 86 WWF World Wide Fund for nature 111 BIBLIOGRAPHY Académie de l’Eau, BRGM, AFD, UNESCO, OIEau, Vers une Gestion Concer- CEDEAO / ECOWAS, 2008, Cadre de prévention des conflits de la CE- Territoire en mouvement Revue de géographie et aménagement. 25-26 tée des Systèmes Aquifères Transfrontaliers Partie I Constat préliminaire - DEAO, janvier 2008. 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