87847

   VEGA FLOOD PREVENTION AND DRAINAGE PROJECT


EXECUTIVE SUMMARY OF THE ENVIRONMENTAL AND SOCIAL IMPACT
  ASSESSMENT OF THE VEGA FLOOD PREVENTION AND DRAINAGE
    PROJECT (P145686): HYDRAULIC WORKS IN THE VEGA BASIN


                       April 11, 2014




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1.     GENERAL INTRODUCTION
Background
The Autonomous City of Buenos Aires developed a risk management scheme to reduce the city’s
vulnerability to flooding under the Bank-supported Flood Protection Project (P006052), which
closed in 2006. This project financed the development of the Plan Director de Obras Hidráulicas,
the Hydraulic Master Plan (HMP) for the city. The HMP outlines investments in urban drainage
infrastructure and identifies viable solutions to reduce flooding in the different drainage basins
within the city. The HMP is the roadmap for the city to guide its interventions for flood hazard
management as it establishes priority structural and non-structural measures for sustainable flood
management. The Maldonado and Vega basins are considered the priority areas for investment;
together they comprise over 30 percent of the city’s area and population, are of utmost importance
to the overall city’s transportation system, and are highly vulnerable to the recurrence of flooding.
The city began implementing the HMP under the Bank-supported Urban Flood Prevention and
Drainage Project APL1 (P088220), which closed in 2012. This Project financed a new macro
drainage system in the Maldonado basin consisting of two large tunnels—approximately 10
kilometers and 5 kilometers long and about 7 meters in diameter—which tripled the drainage
capacity and directly benefitted around one million people by reducing their exposure to flood
hazard. The Project also enhanced the city's capacity to analyze flood hazard, to plan and design
future drainage systems, and to better respond to emergencies.
Description of the Vega Flood Prevention and Drainage Project (P145686)
The Vega Flood Prevention and Drainage Project—currently under consideration for financing by
the World Bank—would support the city of Buenos Aires’ ongoing effort to implement the HMP by
carrying out the planned works in the Vega basin, completing the pending portion of the works in
the Maldonado basin, supporting interventions in the Cildáñez basin associated in part with the
Maldonado drainage system, and implementing various non-structural measures identified in the
HMP that were not implemented under the previous Bank project.
The proposed Project Development Objective is to reduce the risks and impacts of flooding in the
Maldonado, Vega, and Cildáñez watersheds of the Autonomous City of Buenos Aires. The total
Project cost is US$ 300 million (US$ 138 million of Bank financing). The Project has three
components:
    Component 1: Institutional Development for Flood Risk Management. This component will
     support the creation of a modern and sustainable framework for flood risk management within
     the city of Buenos Aires. Component 1 will finance : i) an integrated hydro-meteorological
     observation, monitoring, alert, alarm and response system to increase the City of Buenos Aires
     severe weather forecasting capacity, improving flood preparedness, and emergency management
     and recovery; ii) the development of a probabilistic flood risk model to design a flood risk
     financing and protection scheme to enable the City of Buenos Aires to reduce fiscal outlays on
     post-flood compensation payments, introduce a defined maximum risk retention and a “stop
     loss” risk transfer to the global capital markets; iii) Social Communication and Education to raise
     awareness among city dwellers about flood risk to shift their behavior from a mere recovery
     perspective to a more proactive response prior to flood event and finally iv) Capacity Building
     for the inter-institutional organization in charge of implementing the Hydraulic Master Plan and
     institutions in charge of infrastructure planning, emergency response, and operation and
     maintenance of the City's existing drainage infrastructure.


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   Component 2: Flood Mitigation Infrastructure. The component will support works aimed at
    increasing the safety of people living in flood-prone areas of the city and reducing associated
    social and economic losses, especially for the vulnerable population who is often at a higher risk
    due to precarious living conditions. This component will finance flood mitigation works in three
    of the city’s drainage basins:
     - Sub-Component 2.1) Vega basin. Construction of i) one large drainage tunnel approximately
       8.4 kilometers long and its complementary works, and ii) about 9.8 kilometers of secondary
       and tertiary drainage networks. Component 2 will also fund independent, specialized
       supervision of the tunnel construction works;
     - Sub-Component 2.2) Maldonado basin. Construction of nearly 33 kilometers of secondary and
       tertiary drainage conduits; and,
     - Sub-Component 2.3) Cildáñez basin. Several interventions that include i) improvements to the
       existing conduits to increase the drainage capacity of the lower lands of the Cildáñez basin,
       thus reducing the likelihood of flooding, and ii) the repurposing and environmental restoration
       of Lake Soldati to be used as a permanent flood retention/equalization reservoir and its
       integration into an ampler green, recreational area.
   Component 3: Project Management. This component will finance the project coordination
    unit, project technical and financial audits, monitoring and evaluation, capacity building and
    training, and other operating costs.
Project context, including World Bank’s Safeguards Policies aspects
The Project is located in the city of Buenos Aires, capital of Argentina. The city is situated on the
south bank of the La Plata River, has a surface area of approximately 200 square kilometers, and a
population of approximately 3 million inhabitants (8 percent of the national population). The
specific works and improvements under Component 2 will be located in the Vega, Maldonado, and
Cildáñez basins. The Maldonado and Vega basins comprise over 30 percent of the city's area and
population and cover the central area of the city. The Cildáñez basin covers a suburban area in the
southern part of the city of Buenos Aires (3131 hectares) and is populated by around 290,000
inhabitants; the low basin, the primary target of the envisioned interventions under Sub-component
2.3, is populated by around 50,000 low-income residents who dwell in informal settlements and
precarious social housing. The long history of man-made physical modifications to the city has
caused the existing natural habitats’ conditions to be almost entirely replaced by urban components;
no natural habitats or environmentally sensitive areas are present in the zone directly affected by the
projected works. No known or suspected archeological sites have been documented in Project
related studies or literature in areas that would be directly impacted by the works.
The Autonomous City of Buenos Aires will be the Borrower of the Bank loan under a Guarantee
Agreement with the Federal Government of Argentina. The Ministry of Finance, through its Unit
for Multilateral Financing (UMF) will be responsible for overall Project coordination and will be
the Bank’s main counterpart. With this purpose, the MoF will set up a Project Coordination Unit
(PCU) within the UMF that will preserve the continuity of the team of specialists that has been
taking part in the preparation of the Project, including a senior environmental specialist and a senior
social specialist (the latter is also a World Bank’s former staff). The Ministry of Urban
Development (MUD) will be the implementing agency of Component 2 and will be responsible for
all the technical tasks relating to the works, including Bank safeguard related issues. The MUD is
leading the development of the corresponding environmental and social safeguards documents,
consultations, and processes. The MUD has demonstrated capacity for carrying out the envisioned


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activities based on the results from the previous loan. The MUD has staff and experience related to
Bank safeguards management. In addition, the MUD will strengthen its socio-environmental team
to ensure effective and adequate capacity during Project implementation. Also, the PCU’s social
and environmental experts will perform the general supervision of safeguard compliance.
Component 3 provides resources to support the MUD and PCU safeguards management.
The potential positive impacts and long-term outcomes associated to the Vega Flood Prevention and
Drainage Project are related to the city’s increased resilience to flooding events. They include the
improvement of the population’s quality of life, a reduction in related economic losses, and the
efficient delivery of essential services such as energy, transportation, health and education, among
other benefits. In addition, the development of large scale drainage infrastructure will boost the
construction sector and create jobs. Anticipated potential positive impacts to the Cildáñez basin also
include the betterment of sanitation conditions for the vulnerable residents who live in informal
settlements around Lake Soldati, and the improvement of the environmental and aesthetic
conditions of the lake and its surroundings, opening up the possibility of a recreational area not only
for the immediate neighbors but also for the people living in the watershed.
The proposed Vega Flood Prevention and Drainage Project is classified as Category A according to
World Bank Environmental Assessment OP/BP 4.01 based upon one of the flood mitigation works
to be developed under Component 2, specifically the large drainage tunnel and its complementary
works in the Vega basin (Sub-component 2.1), even though the associated potential socio-
environmental adverse impacts are not considered irreversible or non-mitigable.
Envisioned works under Sub-component 2.2, in Maldonado basin, and Sub-component 2.3, in
Cildáñez basin, are expected to have few potential adverse effects, are site specific, non-irreversible,
and can be readily mitigated.
No potential resettlement related impact is foreseen for the Vega and Maldonado Sub-components;
potential resettlement related impacts, although mostly partial, temporary or individual in nature,
have been identified in connection with the Cildáñez Sub-component.
Activities of Component 1 and Component 3 do not represent significant potential negative
environmental impacts. Instead they will enhance the positive outcomes, long-term benefits, and
sustainability of the Project.
Given that three different works and interventions in three different areas of the city are envisioned
under the proposed Project, Component 2, three separate, specific EA instruments have been
developed in accordance with the World Bank's Environmental and Social Safeguards Policies:
(i) related to Sub-component 2.1 and Sub-component 2.2, an Environmental and Social Impact
    Assessment (ESIA), including an Environmental and Social Management Plan, has been
    developed for each of the hydraulic works1; and,
(ii) related to Sub-component 2.3, an Environmental and Social Management Framework (ESMF)
     has been developed. It has been identified that civil works involved in sub-projects may affect a
     small number of houses in the informal settlements around Lake Soldati; therefore, a


1
  The MUD hired a specialized consulting firm (IATASA) for the development of the ESIA of Sub-component 2.1
(Vega basin). The MUD developed the ESIA of Sub-component 2.2 (Maldonado basin), with the support of two hired
external specialist consultants.



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     Resettlement Policy Framework (RPF) has been prepared in accordance with the World Bank
     Operational Policy 4.12 on Involuntary Resettlement and incorporated into the ESMF2.
Executive Summary of the ESIA of the Vega Flood Prevention and Drainage Project (P145686):
Hydraulic Works in the Vega Basin
The following sections of this Executive Summary will focus on the ESIA of the Sub-Component
2.1 projected works (integrated under the denomination “Hydraulic Works in the Vega Basin”),
which is the Category A sub-project of the proposed Vega Flood Prevention and Drainage Project.
ANNEX 1 presents a brief summary of the environmental and social aspects in the Project’s Sub-
components 2.2 and 2.3.

2.    SUB-COMPONENT 2.1: HYDRAULIC WORKS IN THE VEGA BASIN
2.1. INTRODUCTION
The projected works under Sub-Component 2.1 will provide the area of the Vega basin a new
drainage system that will significantly increase the level of protection and reduce social and
economic losses caused by flooding. The Vega basin (around 1700 hectares of surface area), covers
a central area of the city and is populated by around 280,000 people. An estimated 1 million people
transit the basin daily for work, shopping, commuting to school, and other activities. Today, the
Vega basin over-flows frequently, causing disruptions to the entire city of Buenos Aires by blocking
the vital transportation network (road, railway, and subway) that links the districts in the North to
downtown and to the industrial, populous areas of the South.
The current drainage system in the Vega basin dates back to the 1930s and 1940s and is comprised
of one main underground collector and conveyance tunnel (emissary) and a network of secondary
drainages. The system was designed assuming 30 millimeters rainfall events, duration of half an
hour, and a large infiltration coefficient. Nowadays, natural drainage patterns have been completely
modified as a result of expanding urbanization. Consequently, the soil’s absorption capacity has
diminished (only about 7 percent of the basin is urban green space: public spaces—parks, squares,
etc.—, private gardens, and urban trees) and storm water run-off has dramatically increased. In
addition, severe rainfall events driven by increased climate variability have become more frequent
and destructive in recent years. The existing urban drainage system is then under-designed and
needs to be upgraded to increase its capacity to evacuate large amounts of rainfall from the streets.
Investments under this Sub-component, integrated as the Hydraulic Works in the Vega Basin
project, comprise the construction of i) one large drainage tunnel with an estimated length of 8.4
kilometers—which will act as a second emissary for the Vega stream, doubling the capacity of the
existing one—and its complementary works; and ii) around 9.8 kilometers of secondary and tertiary
drainage networks. This infrastructure will be able to handle rainstorm events of up to 10 years of
recurrence periods and two hours of duration (which are critical for the basin), reducing the
likelihood of flooding from 50 to 10 percent. In this way, flooding would be less frequent and
consequences less significant.


2
 The MUD developed the ESMF of Sub-Component 2.3 (Cildáñez basin), including the RPF, with the support of the
environmental and social experts hired by the MoF and the city’s Ministry of Environment and Public Space.



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A full ESIA has been developed for the Hydraulic Works in the Vega Basin. The ESIA addresses
the background (planning stage—city’s HMP preparation, including project alternatives analysis,
and early consultations); establishes environmental and social baseline conditions; identifies and
assesses potential environmental and social adverse impacts and risks based on the type and scope
of physical interventions and site characteristics, as well as expected benefits; designs mitigation
measures; and presents an Environmental and Social Management Plan (ESMP) for the proper
management of works during construction and operation stages.

2.2. ANALYSIS OF ALTERNATIVES
During the planning stage (preparation of the city’s HMP) the project identified and analyzed, on a
pre-feasibility basis, four strategic alternatives for the management of floods in the Vega basin. The
main options for flood protection that were considered are (i) different levels of protection: 5, 10,
and 20 years of storm recurrence periods; and (ii) different control systems and combinations of
them (conveyance tunnel, storage reservoirs). Only the manual or conventional method for the
construction of the conveyance tunnel was considered during the planning stage; it essentially
covered the works’ technical requirements and its cost was significantly lower when compared to
the use of Tunnel Boring Machine technology (TBM). The construction of additional secondary and
tertiary drainage conduits to reinforce the network in the basin was considered in all the
alternatives. The hydraulic modeling of the different solution alternatives was performed with the
help of the software package InfoWorks CS. The goal was to seek a solution that would afford the
city of Buenos Aires protection against floods associated with rainfall events having return periods
of up to 10 years, while mitigating the impact of storm events with return periods larger than a
decade.
The alternatives were analyzed from technical, economic and socio-environmental perspectives,
applying a multi-criteria evaluation analysis. Protection levels, initial investment costs, operation
and maintenance costs, beneficiary population, averted damage and potential social and
environmental impacts—during the construction and operation phases—were the main comparison
criteria. Identification and evaluation of potential social and environmental impacts were based on a
specific expedited environmental assessment of the different alternative works, considering the
main characteristics of each one and the socio-environmental sensitivity as described in the
preliminary studies that were carried out for the development of the basin baseline.
As a result of this analysis, the following alternative was originally selected: i) construction by
manual method of a tunnel of approximately 8,400 meters long with tunneling or access shafts
every 500 meters and two vents to evacuate air accumulated inside the tunnel; ii) six flow diversion
chambers; iii) an outlet shaft on the riverbank of the La Plata River; and, iv) a pump station for
maintenance purposes. The tunnel alignment was entirely placed under existing streets and/or public
space; complementary works were also located in city-owned land.
At the present design stage of the Vega hydraulic works, an advanced executive project design for
the Vega basin has been prepared (note: the project contract for these works will consist of the final
detailed design and construction). The advanced executive project re-analyzed the alternative
originally selected taking into account the present conditions and the experience acquired. As a
result, the alternative was adjusted mainly in one aspect: approximately 6 kilometers of the tunnel
will be built using a Tunnel Boring Machine of the Earth Pressure Balance type (TMB-EPB) due to
i) its optimal technical aptitude to operate at significant depths and, consequently, its ability to
minimize the risk of disturbing the existing underground relevant infrastructure (such as a master

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aqueduct and two subway alignments—only one subway crossed the area of the works location at
the time the HMP was prepared—); and ii) the minimization of construction impacts on the surface
(e.g., noise, dust emission and disruptions in normal urban movement). The advantages of the
TMB-EPB method were observed in the successful implementation of the APL1.

2.3. HYDRAULIC WORKS IN THE VEGA BASIN PROJECT DESCRIPTION
I) The new drainage tunnel and complementary works for the Vega basin consist of the following:
a) A 8400 meters long tunnel (with a 0.05 to 0.4 percent gradient) for the Second Vega Emissary.
      (i) approximately 2400 meters will be excavated by classic procedures: 1700 meters of
           gallery section (1.60 x 2.45 meters) and 700 meters with horse-shoe section 3.5 meters
           in diameter; approximately 10 to 15 meters of overburden; and,
      (ii) approximately 6000 meters will be built using a TBM-EPB: approximately 5.90 meters
           of total diameter and 5.30 meters of effective diameter; approximately 23 to 30 meters
           of overburden and up to 20 meters of groundwater pressure.
   Definition of the longitudinal profile of the tunnel was conditioned by the presence of the
   existing emissary where the new drainage tunnel would be developed under it, the tunnels of
   subway lines “B” and “D”, a master aqueduct of 4.60 meters in diameter, and several
   underground conduits (water and sewage) of less than 1.60 meters in diameter. Tunneling
   longitudinal profile design assumes a clearance above the top of the tunnel and the conflicting
   utilities of about one diameter (6 meters) in order to minimize potential effects from excavation
   activities. The tunnel will be built entirely under paved roads or public spaces. The total tunnel
   excavation volume will be of approximately 210,000 cubic meters.
b) Two vents to evacuate air accumulated inside the tunnel.
c) Outlet shaft (future discharge chamber into the La Plata River). Approximately 30 meters of
   total depth and 27 meters of useful depth; 35 meters in inside diameter, including 0.30 m of
   impermeable cladding. Chamber vertical structure will be constituted by cast concrete walls (1.2
   meters wide and approximately 53 meters depth, then reaching the underlying rock —Paraná
   Formation—) executed using a hydro milling machine, method that will allow a minimal
   disturbance, the excavation of the shaft under “dry” conditions—whit a consequent reduction of
   construction risks and accidents—, and the minimization of risks of structural failure of the
   shaft during both construction and operation phases. The foundation of the chamber will reach
   the underlying rock also in order to avoid floating effects. The chamber is also designed to
   mitigate the effects of the frequent high tides in the La Plata River that hamper the discharge of
   storm water from the drainage system. The shaft will also serve as a temporary access for the
   tunneling machine during construction. The advantages of this construction method and
   technical provisions were also observed in the successful implementation of the APL1. These
   works will be located in a city-owned sector on the riverbank. Excavation volume will be of
   approximately 30,000 cubic meters.
d) Pumping Station to be located in the outlet shaft installation. Pumping systems will only be
   installed for maintenance purposes since water will flow by gravity.
e) Three vertical access and connection shafts (approximately 13 to 28 meters in depth). One shaft
   will allow the connection between the segment of the tunnel built by conventional method and
   the one built by tunnel boring machine method; the boring machine shield will be lost during
   these works (it will not be recovered) in order to avoid further disruptions on the surface. The

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   other two vertical shafts will allow the connection of two existing master secondary drainage
   conduits to the TBM tunnel segment. All these shafts will be excavated under streets.
f) Six flow diversion chambers. These chambers will connect existing and future secondary
   drainage conduits to the new tunnel. They will be built under streets.
II) The existing storm water secondary and tertiary drainage network will be reinforced by the
    construction of 9.8 kilometers of conduits that will extend throughout the area of the Vega
    basin. They will be built beneath paved roads, by open trench method, with precast concrete
    (circular section up to 2 meters in diameter and approximately 1.5 meters of cover) and cast-in-
    place concrete (rectangular section up to approximately 2 x 2.5 meters and approximately 1.5
    meters of cover).
Once this new drainage system is complete and in operation, the maximum flow of storm water
from the new discharge will be of 60 cubic meters per second. Assuming the aforementioned design
parameter (rainfall events having return periods of up to 10 years), this maximum discharged flow
would appear approximately every 10 years.

2.4. REGULATORY FRAMEWORK
Republic of Argentina – City of Buenos Aires
The Constitution of Argentina, since its 1994 reform, establishes the duty of protecting the
environment and the basic right of every person to enjoy a healthy environment. The constitution
also establishes a specific model for the distribution of competences in the federal system: the
Argentine National Constitution vested the federal government with the power to enact rules setting
forth “minimum standards for environmental protection” that apply nationwide, while the 23
provinces and the Autonomous City of Buenos Aires have the power to enact supplementary
regulation to said federal rules. The General Environmental Law 25.675 (one of the above
mentioned national environmental protection rules), states, among other things, that any work or
activity that may significantly affect the environment or the quality of life of people is subject to an
Environmental Impact Assessment (EIA) procedure prior to its execution. Local authorities will
determine the need for an EIA study. In such cases, the studies will address (as a minimum
requirement) a detailed description of the proposed activity, the identification of the consequences
to the environment, and the measures aimed at mitigating the adverse effects. The law also requires
that public consultation be a mandatory stage of the process of environmental impact assessment
and approval of projects.
The Constitution of the Autonomous City of Buenos Aires, in line with the National Constitution,
establishes that every person has the right to enjoy a healthy environment as well as the duty of
preserving it for the present and future generations. It also declares the need for an environmental
impact assessment for those projects considered as having a “relevant effect” (high potential
impact) and the community’s participation through a Public Hearing. According to the local
Constitution mandate, the City set forth its EIA legal system comprised of Law 123 and a series of
complementary and regulatory norms. In general terms, the system provides the EIA technical-
administrative procedure and requirements including the project/activities classification mechanism,
the general minimum contents of the EIA studies, the accreditation of the professionals for
developing such studies, and the public participation component to be carried out.
Local legislation regards the Hydraulic Works in the Vega Basin project as having a high potential
impact. The ESIA study developed by the MUD is aligned with the corresponding guidelines and

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procedures of the local EIA system. The Government of the Autonomous City of Buenos Aires
supervises this process through the Environmental Protection Agency (Agencia de Protección
Ambiental) of the Ministry of Environment and Public Space (Ministerio de Ambiente y Espacio
Público). The MUD initiated the Law 123’s administrative procedure on December 20, 2013. Now
(April 2014), the Environmental Authority is evaluating the ESIA as the first step of the technical
process towards the project approval, which includes, as mentioned above, a Public Hearing.
World Bank Safeguard Policies
The ESIA of the Hydraulic Works in the Vega Basin was developed taking into account the
requirements of the World Bank Safeguard Policies that have been triggered for the proposed Vega
Flood Prevention and Drainage Project (P145686): OP 4.01 Environmental Assessment, OP 4.11
Physical Cultural Resources, and OP 4.12 Involuntary Resettlement (note: OP 4.12 has been
triggered in connection with Sub-component 2.3, in Cildáñez basin, see ANNEX 1). As the future
new drainage tunnel proposed for the Vega stream will discharge storm water into the La Plata
River, an international waterway in terms of OP 7.50 on Projects on International Waterways, this
policy has also been triggered for the Project. In addition, although OP 4.04 on Natural Habitats has
not been triggered for the Project—since it does not involve the significant conversion of natural
habitats and will not take place in protected areas or ecologically important sites—, the ESIA
assessed potential impacts on environmentally fragile areas as part of the EIA process (OP 4.01).

2.5. ENVIRONMENTAL AND SOCIAL CONDITIONS
Project location
The new Vega drainage tunnel will be built under Nueva York, Ballivián, Victorica and La Pampa
streets. The top of the tunnel will be located at a depth ranging between 10 and 30 meters below the
ground surface.
The outlet shaft (future discharge chamber) and pump station will be located in a city-owned sector
on the riverbank of the La Plata River that is commonly known as Saint Tropez Bay. It is foreseen
that the ancillary facilities for the construction of the tunnel (e.g. main camp, factory and deposit of
voussoirs) will be also placed in this sector.
The six flow diversion chambers will be located in the following street intersections: Nueva York
and Helguera; Constituyentes and Ballivián; Barzana and Ballivián; Victorica and Ballivián;
Lugones and La Pampa; and Elcano and Zapiola.
The three vertical access and connection shafts will be located in the following street intersections:
Lugones and La Pampa; Cramer and La Pampa; and, Victorica, Triunvirato and La Pampa.
The conduits to be built to reinforce the secondary and tertiary drainage networks will be placed in
several different sectors of the basin in segments (between approximately 100 and 1,800 meters
long) of the following streets and avenues (beneath paved roads): Concordia, Helguera,
Constituyentes, Victorica, A. Thomas, Lugones, Roseti, Donado, Delgado, Tronador, Elcano,
Balbín, Sucre, Freire and Cabildo.
The need, and subsequent installation of secondary construction base camps/laydown areas for
materials storage, will be defined based on the final design of the project (part of the project design-
construction contract) and the particular circumstances that could arise during the execution of the
works. Thus, the contractors will ultimately define the sites for these ancillary facilities, which may
be located in their own premises, in public land or in plots acquired (rented) by voluntary

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agreements. However, the ESIA establishes detailed conditions to appropriately select the location
of secondary construction base camps/laydown areas, if needed, and identifies six possible apt sites
(placed in public land) in order to assess the potential impacts associated to such installations.
Similarly, the main disposal site(s) for soil from excavations (estimated in around 250,000 cubic
meters) have not been established at this advanced executive project design stage. The city will
identify and select the specific location(s) of soil disposal site(s) during works execution based on
the quality characteristics of the excavation materials and construction needs (e.g. part of the soil
may be used as soil cover in diverse components of the works). The city will be the owner of the
material, and will be responsible for the appropriate selection of disposal site(s) for exceeding soil
from excavations and the management of the disposal (no involuntary use or taken of land is
foreseen in connection with the disposal site(s) selection)3; future final design and construction
contractor of the works will be responsible for the management of material transportation. However,
the ESIA has preliminarily identified four potential sites for the disposal of exceeding soil from
excavation, which are located in the North, the South (two sites), and in the West of the city—three
of them situated in the territory of the Province of Buenos Aires—, in order to assess the availability
of such sites, the proper conditions of disposal and the management of material transportation.
Environmental and Social Area of Influence
The area of environmental and social influence—direct and indirect—has been determined based on
the location of the project components and the extent of predicted impacts on each of them.
The Area of Direct Influence (ADI) is defined as the area that will benefit from the new drainage
system once it is operational, which is the geographically-delimited area of the Vega Basin of
approximately 1700 hectares. The ADI also includes the water surface area that will be receiving
the storm waters from the new discharge point (on the La Plata River surface, with an influence
zone up to 200 meters measured from the coastline).
An Operational Area (OA) has been established within the ADI. This is the area that is expected to
be directly affected by the main, complementary, and ancillary works during the construction stage.
The OA extends around 300 meters on each side of the tunnel alignment (specific considerations
were made in certain parts) and surrounds, in approximately the same proportion (also with
particular considerations in certain cases), the “sensitive spots”. Environmentally and socially
“sensitive spots” (due to surface works such as the construction shafts, connection and derivation
chambers, etc.) have been located within the OA in coincidence with the above mentioned sectors,
street intersections and street segments.
The Area of Indirect Influence (AII) comprises the total area of the city’s territorial units (Comunas)
involved with the Vega Basin (No. 11; 12; 13; 14 and 15)—around 7400 hectares—since it is the
socially-delimited area that has a vested interest and will be ultimately benefited by the works. The
Comunas have been conferred of political and administrative management powers as well as
territorial competences to promote and facilitate, among other things, the public’s participation in
government decision-making processes, the control over activities taking place in their territories,
and the preservation of the cultural identity of the constituent neighborhoods. Then, although a large

3
  This approach is similar to the mechanism used during the implementation of the APL1, in which a much larger
amount of soil was involved (around 700,000 cubic meters). Exceeding soil from excavations was used to fill depressed
areas of flat lands in the Province of Buenos Aires in compliance with provincial and municipal regulations.



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part of this area will be not directly or indirectly affected by the foreseen interventions, it comprises
favorable social and structural conditions to effectively influence the project as well as to perceive
and receive the benefits—even induced, weak benefits—of the execution of the hydraulic works in
the Vega basin.
Environmental and Social Baseline
Biophysical setting
The ADI is located in a zone of temperate-wet climate, with mild winters (average temperature in
July 8.9°C) and hot summers (average temperature in January 26°C).
Annual average precipitation (normally rain, occasionally hail) is 1306.3 millimeters, according to
the National Meteorological Service (NMS, 2001-2010 data series). There are about 102 days of
precipitation per year (considering values above 0.1 millimeters); March has the highest number of
rainy days, 10, and April the least with 6.6 days. The average humidity is 71.1 percent.
Strong winds of more than 40 kilometers per hour are common year round, especially between
September and March, with an annual average frequency high of 119 days (NMS, 1981-2010 data
series). Calm annual average frequency is relatively low (46/1000 days). Wind average speed is
15.6 kilometers per hour. More frequent winds in the study area come from the East (frequency of
21.5 percent) and NE (frequency of 11.9 percent). There are also local winds, which produce
regional effects; the most relevant one in connection with the Vega basin’s flood events is the
Sudestada, a persistent, moderate-to-strong wind from the SE (speeds between 20 and 40 to more
than 70 kilometers per hour, frequency of about 8 percent). The Sudestada produces exceptionally
high tides in the La Plata River, impeding the normal discharge of water from the drainage system.
The La Plata River is the most important surface water resource of the study area (all the streams
that traverse the city of Buenos Aires are transitory flows and are currently culverted) and the main
drinking water source for the Metropolitan Area of Buenos Aires (MABA). The La Plata River is
actually an estuary that receives waters principally from other two important, large volume rivers:
Paraná and Uruguay Rivers. The average yearly flow of the La Plata River is 22,000 cubic meters
per second. The La Plata River has suspended solids in a wide range of concentrations, from 15 to
250 milligrams per liter, predominantly fine (slime and clay), which give the river its characteristic
brown color.
The La Plata River is the receiving body of the present Vega basin discharges and, directly or
indirectly, of all the MABA basins discharges. It is subject to pollution from domestic and industrial
waste. Monitoring of the river’s water quality is performed by several entities such as the Water and
Sanitation Service Company of the MABA (AySA), the Matanza-Riachuelo Basin Authority
(ACUMAR), and the Navy Hydrographic Service. Hydrologic characteristics of this river favor
higher concentrations of contaminants in a relatively narrow strip, approximately 500 meters wide
measured from the coastline, which is seriously compromised due to the presence of physical and
bacteriological contaminants. Based on concentrations of nitrogen substances (NH4+ / NO3-), Total
Cr, Pb, detergents, phenolic substances, BOD, and fecal coliforms, this coastal zone could be
considered as Type III Use (non-apt for recreational purposes with direct contact), according to a
regional guideline on water quality (ACUMAR).
The region has suffered deep modifications after hundreds of years of human occupation. As a
consequence, original upper soils have practically disappeared, and the original topography has
been modified by extraction or substitution of soil components. The soil matrix is highly

                                                   11
heterogeneous and variable in its constitution, surface development, and depth. In general terms,
characteristics of the region’s deepest soils are associated with different levels of water saturation
and moderate to low permeability, relevant aspects in connection with runoff and flooding.
There are two relevant groundwater systems in the ADI:
(i) Epipuelches is a multilayer aquifer located in the Pampeano sediments (aquifer of medium to
    low productivity) and Postpampeano sediments (mostly an aquitard with waters of a high saline
    content). Pampeano sediments are not present in the Vega low basin area and in the La Plata
    River riverbank. The water table in the shallow layers of the sediments ranges between 2 and 15
    meters below surface elevation and generally follows the surface morphology. The water table
    presents high levels of diverse chemical, physical, and biological contaminants originated by
    human activity. Based on its productivity and quality, this aquifer is not exploited in the ADI;
(ii) Puelches is located in the Puelchenses sands underneath the Epipuelches aquifer and separated
     from it by a low permeability layer of clay. The Puelchenses sands, which are found at an
     average depth of 30 meters below surface elevation, rest on the impermeable Paraná aquiclude
     (underlying rock). The Puelches is a semi-confined aquifer; the layer of clay makes difficult but
     does not impede a low natural circulation of groundwater (ascendant and descendant) between
     the Puelches and Epipuelches aquifers. The Puelches is an extensive (it extends beyond the City
     and even the Province de Buenos Aires) and very productive aquifer with a large amount of
     water that is safe for human consumption, irrigation, and industrial uses. However, its quality
     diminishes towards the La Plata River. Specifically, in area of the Vega basin the Puelches
     aquifer is affected by high levels of NO3- and also, in the low basin, by high saline contents. At
     present, in the ADI it is only used in limited amounts for industrial purposes.
Air quality in the area is principally affected by combustion exhaust gases, basically from vehicles,
and to a lesser extent from industries. The Environmental Protection Agency of the City of Buenos
Aires (APRA) monitors NOx, SO2-, CO, particulate matter < 10 microns (PM10) and O3 by air
quality monitoring stations (US-EPA type) located around the city. Based on NOx and SO2-
measured values, the ESIA performed a modeling study that shows that concentration levels of
those contaminants are medium to low in the ADI (below the air quality reference values, Law
1356). APRA also monitors total settleable particulate matter (following ASTM standards) in four
points of the city, two of them located in the AII; measurements are below, but near, the reference
value (1 milligram per square centimeter in 30 days, Law 1356).
The main sources of noise in the study area are traffic, construction works, and sports events. The
city of Buenos Aires has 18 noise continuous monitoring stations, three of them located in the AII.
Based on data collected at these locations (2012), the weekly average level of noise is around 73
decibels during daylight hours (7:01 am – 10:00 pm) and around 69 decibels during night hours
(10:01 pm – 7:00 am). Both are above the Type III reference values (Tolerable noisy areas, < 70
decibels daylight hours and < 60 decibels night hours, Law 1540). A specific study on noise was
developed for the project’s ESIA. Noise measurements were taken in 31 points around the sensitive
spots of the OA during daylight hours. Registered results show that noise is < 60 decibels (Type I)
in only four points (intersections of the streets Ballivián and Barzana, Helguera and Nueva York—
two points—, and Helguera and Asunción); between 60 and 65 decibels (Type II) in eight points;
between 65-70 decibels (Type III) in six points; and > 70 decibels in 13 points, which correspond to
intersections with the main avenues of higher traffic in the OA (Costanera Rafael Obligado Ave,
Cabildo Ave, Triunvirato Ave and Constituyentes Ave).


                                                  12
No known or suspected archeological sites have been discovered while performing project related
studies or documented in literature in areas that would be directly impacted by the works; however,
the underground of the city of Buenos Aires could be considered of archeological potential and even
of paleontological potential in deeper sedimentary strata.
The city of Buenos Aires is located in a zone of Seismic Hazard 0, Minimal, according to the
classification of the National Institute of Seismic Prevention.
The long history of man-made physical modifications to the city has caused the existing natural
habitats’ conditions to be almost entirely replaced by urban components. There are not areas of
significant natural habitats or critical natural habitats in de ADI. The protected area closest to the
ADI is the Ecological Preserve “Ciudad Universitaria - Costanera Norte” (created by Law 4467,
issued in December 2012 and published in the city’s Official Gazette in February 2013), which is
located on the Eastern boundaries of the AII (the La Plata River), upstream of the future discharge,
about 2 kilometers from the OA and 1 kilometer from the ADI. The Ciudad Universitaria -
Costanera Norte ecological preserve is a wetland, a coastal habitat of around 18 hectares in area
that emerged from the spontaneous colonization of debris dumping throughout the years by both
native and exotic flora and fauna. It is enclosed by the campus of the Buenos Aires University, a
riparian public park and the outlet of the White Stream to the La Plata River.
In regards to flora, the most important ecosystem in the study area is urban trees. From an
ecological point of view, this community has limited value but plays the role of a primary producer,
birds’ habitat, etc. The ADI has around 45,800 trees of about 280 different species (mostly exotic,
87 percent). About 5800 trees are located in the open green areas of the basin (85 parks, squares and
others, around 91 hectares, 5.35 percent of the basin area) and the rest, around 40,000, are street
trees. Regarding the OA and the defined intervention sectors on surface (sensitive spots), the
abundance of street trees is relevant along i) the corridor Nueva York-Ballivián, in connection with
the tunnel construction; and ii) Elcano Ave, Rosetti Street, Lugones Street, and Parque Chas
neighborhood streets, in connection with the secondary and tertiary conduits construction.
In regards to fauna, it basically comprises rodents, small reptiles that can take refuge in existing
vegetation, and a relatively important variety of birds (around 50 species), which represent the most
populous and dynamic fauna of the city. The most common bird species are those better adapted to
live in man-made modified environments, such as the gorrión (Passer domesticus) and the paloma
doméstica (Columba livia), both exotic.
Social setting
According to the National Population Census of 2010, population within the AII comprises
1,029,823 inhabitants (more than a third of the total city’s population of 2,890,151 inhabitants); 46
percent male and 54 percent female. Average density of population is 138 inhabitants per hectare,
while the density of the City of Buenos Aires is 142 inhabitants per hectare. However, there is a
tendency towards increasing the intensity of soil occupation: new building constructions permits in
the city have increased 76.1 percent between 2010 and 2011 and from the city’s total (21,610) 43
percent are targeted to the AII.
In the AII, the land use is predominantly residential and commercial. Commercial use is particularly
relevant in three Comunas (No. 14, 29.8 percent; No. 13, 22.8 percent; and No. 15, 22.6 percent).
The presence of industries is not relevant to the AII (only around 3.5 percent of the total amount of
economic activities and mostly of a low scale).


                                                 13
The literacy rate of the population of 10 years old or more in the AII (99.8 percent) is higher than
the city’s one (99.5 percent). Similarly, 40 percent of the AII population has completed the
university level of education, while this parameter is 32.2 percent for the city total population.
According to the 2011 Annual Household Survey of the city of Buenos Aires, the AII is an area
with one of highest rates of economic activity of the city (more than 72 percent in the AII, 70.8
percent in the city). Households with some type of medical insurance reach 91 percent.
The AII has 1170 education centers of different levels of education (distributed in about 900
buildings) and 28 healthcare facilities. In addition, 66 museums, 77 theatres, 7 cultural centers, 29
libraries and 14 relevant cultural institutions, such as the Planetarium of the city of Buenos Aires,
are located in the AII.
Regarding the ADI, it is populated by around 280,000 people. The highest population density is
found in the triangle formed by the avenues Del Libertador, Luis M. Campos and Olleros, and, in
addition, in the strip located between the two railways Belgrano Barrancas and Belgrano R to the
West of La Pampa street. This zone, included in part within the OA, has a population density that
ranges from 300 to more than 900 inhabitants per hectare. The axis of this extensive densely
populated area is Cabildo Ave. There are other punctual sectors of high population density, but in
general terms, the rest of the ADI is of medium to medium-low population density.
The ADI comprises one of the most active and populous commercial areas of the city (around ten
blocks along Cabildo Ave and their intersecting streets), included in part within the OA. Industries
are barely present in the ADI. Some sectors of the ADI are assigned for special infrastructure, such
as the Airport of the city of Buenos Aires and important sports facilities. There are also several
relevant parks and squares, such as San Benito, De Las Américas and El Salvador.
Based on a project’s ESIA specific analysis, the ADI contributes more than 40 percent of the total
city household’s taxes. In general terms, the population in the ADI belongs to the middle and upper
classes. Punctual sectors of less affluence, or even poverty, can be found towards the Southwestern
part of the ADI in the Comunas 11 and 15. There is some social housing and an informal settlement
located in the area (the latter placed around Fraga and Palpa streets, comprising about 2 hectares
and 5000 people).
219 education facilities are situated in the ADI, with 143 of them placed in the OA. The ADI has
also 14 healthcare facilities, several ones of high significance within the city, and even MABA’s
public healthcare system; 8 healthcare facilities are placed in the OA. Four police stations and two
fire stations are also placed in the OA.
The ADI is crossed, on the surface and underground, by diverse infrastructure and basic service
facilities. Main transport infrastructure comprises i) a significant network of roads with high rates of
traffic flow, more than 50 public transport bus lines, and several arteries of heavy traffic; ii) four
train railways and their ten stations; and, iii) two subways and their 6 stations. Basic services
facilities comprise i) underground networks of sewage and water pipelines (including four main
aqueducts of 2.60 meters, 3.00 meters, 4.20 meters, and 4.60 meters in diameter); ii) underground
networks of low, medium, and high pressure natural gas pipelines; and iii) surface and underground
networks of electricity transmission lines.
The ESIA presents detailed tables, maps and graphics of the diverse existing facilities and
infrastructure in the ADI/OA, and the relevant interferences in connection with the projected works.



                                                  14
The ADI possesses a high level of urbanization, with three relatively differentiated zones in regard
to land uses and landscape: i) the upper and a portion of the medium basin, predominantly
residential, characterized by low buildings, abundance of private gardens and street trees; ii) the
medium and a portion of the low basin, predominantly residential and commercial, characterized by
high-rise buildings, high population and vigorous commercial activity; and iii) the low basin,
predominantly residential and of special uses, characterized by the larger open green areas within
the ADI and the urban riparian landscape. The OA traverse the ADI longitudinally; thus, it presents
the same predominant land uses and landscape features as the ADI along its alignment.
In regards to the protection of urban patrimonial values, the Autonomous City of Buenos Aires has
two legal categories: Áreas de Protección Histórica (HPA, Historic Protection Areas)4 and the
Catálogo de Edificios Protegidos (Protected Buildings Catalog). Eight HPA have been established
by the city within the limits of the ADI. Six of them are located in the OA; however, none of the
identified sensitive spots are placed in HPA areas. Besides, foreseen works on the surface will take
place on roads without permanently disrupting the existing urban setting. No Protected Building is
placed in the OA.
To sum up, the AII (in which the ADI is included) is important economically and socially and
improved flood control would therefore have significant social and environmental benefits for the
region and even for the whole city. The AII and ADI are mostly of interest from a strategic
perspective. The OA is the area most likely to be impacted by construction works and therefore of
most interest from the point of view of potential construction related environmental impacts; given
its highly developed state some likely incremental adverse environmental impacts are going to be
minor or even negligible in certain sectors.

2.6. EVALUATION OF ENVIRONMENTAL AND SOCIAL IMPACTS
The ESIA made a detailed and systematic identification and analysis of the potential impacts that
could arise as a result of the final design (detailed engineering), construction, and operation of the
Hydraulic Works in the Vega Basin project.
Based on the detailed description about the characteristics of the proposed infrastructure and a
characterization of the social and environmental baselines, the type and magnitude of impacts on the
atmosphere, soil, water, geology and geomorphology, vegetation and urban trees, avifauna,
population, economic activities, infrastructure and services, facilities, cultural patrimony, urban
circulation, territorial structure and landscape, were estimated.
This has been done by using a series of matrixes that correlate project components (as a detailed
itemization of the main diverse individual works/actions associated to each component) during the
different stages of implementation to the different environmental and social compartments
(characteristics or factors of the biophysical and social settings capable of being affected by the
actions associated to the works). Then the types of impacts are rated by qualification, quantification,
weighing, and a combination of several attributes: sign (positive/negative), intensity
(low/medium/high), duration (transitory/permanent), occurrence (short/medium/long term), affected
area (punctual—sensitive spots—/OA/ADI/AII). The full description of the applied methodology

4
  According to the Urban Planning Code of the city, under this denomination are included “… areas, places or urban
groupings that, due to their historic, architectonic, singular or environmental values, constitute settings clearly
recognizable as referents of our culture”.



                                                        15
for the identification and assessment of the potential impacts and the corresponding results of their
qualitative and quantitative analysis are presented in the ESIA report.
In summary, the environmental adverse impacts of the construction stage are considered more
important than those of the operational stage (details on impacts are provided below), although they
are mitigable with the application of relatively routine/standard mitigation measures. The project
does not contemplate any physical displacement (resettlement) or loss of economic activity.
Final design phase
The main estimated impact is the positive increased awareness of the community that would rise
from the communication and consultation process of the project. The final design will benefit from
stakeholder input.
Construction phase
   Tunnel and complementary works
Predominant potential adverse impacts were found to be of medium intensity, short term
occurrence, with a restricted affected area (principally sensitive spots); effects are mostly transitory.
On the biophysical setting, estimated impacts of highest value affect the air, soil, avifauna and
vegetation and urban trees. They were all assessed as moderate to low. Potential impacts on air
quality (particulate matter emissions, increased noise level) will be generated during the demolition
of paved roads, excavation activities, and operation of machinery. The impacts are mostly limited to
the sensitive spots during specific stages. Potential effects on soil quality are mainly associated to
excavation activities, including water table depression, and risks associated with the works (e.g.
accidental releases of contaminants, technical and human failures); in this case the effect would
extend along the alignment of the tunnel segment to be built by manual methods and sensitive spots.
Potential impacts on avifauna and vegetation and urban trees are mainly associated with road
demolitions, excavation activities, operation of machinery, and risks of the works. Potential impacts
on vegetation and urban trees are also related to the preparation of surface works locations; it could
be necessary land clearance for ancillary facilities installation (basically from bush and other no
significant vegetation) and the potential removal of some trees. These impacts would be transitory
and located in the Operational Area around the sensitive spots.
Potential impacts associated to the disposal of exceeding soil from excavation include alteration of
surface runoff patterns, soil erosion, and visual impacts; they were assessed as moderate and limited
to the disposal sites5. Potential impacts related to the management of soil material transportation
include particulate matter and exhaust gas emissions, increased noise level, and disruptions in
normal urban movement (traffic); they were assessed as moderate, with transitory effects that
extend to the OA.
According to the project design and feasibility technical studies of the new tunnel, the top of the
tunnel segment to be built by conventional methods (approximately 2.4 kilometers) will be located
between 10 and 15 meters below the surface and cut across the Pampeano sediments and the water
table. The rest of the tunnel—built by TBM-EPB method (approximately 6 kilometers)—will be
5
 These impacts have been assessed on a generic basis since, as mentioned above, disposal site(s) of exceeding soil from
excavation will be properly selected by the city during the execution of the works, based on quality characteristic of
excavation materials and construction needs.



                                                          16
excavated at a depth ranging between 23 and 30 meters below surface (tunnel ceiling). This portion
of the tunnel will be mostly located at the base of the Pampeano formation, but a segment of it will
intersect the Puelches formation. The walls of the discharge chamber to be constructed in the
margin of the La Plata River will traverse the Postpampeano and Puelches formations. Foreseen
construction methods and technical provisions would allow structures to be totally isolated from
groundwater and avoid an artificial hydraulic connection between aquifers (mainly by the use of
earth pressure balance for tunneling and the use of hydro milling machine for the discharge chamber
walls construction).
The ESIA analysis shows that the Ecological Preserve “Ciudad Universitaria - Costanera Norte”
will not be directly or indirectly affected by the works, either for construction and operation stages.
On the social setting, the potential negative impacts of highest value, assessed as moderate to high,
affect the population (their quality of life due to discomfort, nuisance, disruptions in normal urban
movement—traffic and pedestrian—and alteration of daily activities), urban circulation (deviations,
increased traffic jumps, etc.), and landscape (its visual perception and quality due to noticeable
modifications in the vicinity of the works), although they will have a transitory effect with a
duration confined to the period of the execution of the works, and at specific stages. Other moderate
potential impacts are anticipated in connection with economic activities, facilities, and infrastructure
and services; they would be transitory impacts. All these potential adverse impacts would affect the
Operational Area of the segment of the tunnel to be built by conventional methods, including its
sensitive spots. Potential impacts on cultural patrimony have also been considered moderate.
There could also be negative impacts related to the occupational health and safety of the staff if
proper safety and health measures are neglected.
As the main works in the Vega basin will take place on or beneath roads and public space, without
private formal or informal occupation or uses that exist at present, no potential locations of land
acquisition or related (such as easement) have been identified and any involuntary use or taken of
land is foreseen for the Hydraulic Works in the Vega Basin project.
The ESIA performed a specific analysis on the potential subsidence from excavation activities. A
risk assessment on buildings located along the tunnel alignment was made; risks proved to be “very
low” and “negligible”. However, future contractors will be required to perform audits and controls
on the conditions of the buildings and infrastructure that could be affected by the works.
None of the estimated potential adverse impacts are anticipated to be significant.
The estimated highest potential positive impacts in the construction stage are the creation of jobs—
some of them highly specialized in large scale infrastructure—, and the creation of informal
economic activities. In addition, the development of large scale drainage infrastructure will boost
the construction sector. In general terms, they would be temporary impacts that may have effects
that go beyond the works completion period.
   Secondary and tertiary drainage conduits
Predominant potential adverse impacts are assessed as of medium intensity, of restricted affected
area, with mostly transitory effects.
On the biophysical setting, the estimated impacts of highest value, assessed as moderate, pertain to
the air and soil: noise, vibration and emission of exhaust gases from machinery; generation and
dispersion of dust; and accidental releases of contaminants are the principal potential impacts. They


                                                  17
will be the result of trenching (including demolition of the paved surfaces and localized depression
of the water table and drainage) and of the inherent risks of the works. These potential adverse
impacts would also affect avifauna, and vegetation and urban trees. Vegetation and urban trees
could be also affected in the same way by the same actions mentioned above in regards to the tunnel
and complementary works construction.
On the social setting, the main potential adverse impacts, assessed as moderate to high, would be on
urban circulation, infrastructure and services and landscape. Impacts assessed as moderate pertain to
population—related to disruptions to normal urban movement (traffic and pedestrian), discomfort,
nuisance, alteration to daily activities, and safety issues—, economic activities and facilities.
Potential impacts on cultural resources due to excavations and soil movements have been
considered moderate to low.
All these potential impacts would appear in the short term, be transitory, and be located within the
OA. None of them are anticipated to be significant.
Similar to the tunnel construction, estimated highest potential positive impacts are the creation of
job and of informal economic activities. They would be mostly temporary impacts.
Operation and Maintenance phase
   Tunnel and complementary works
Predominant potential impacts are positive, of high to medium intensity, with the ADI as the area of
influence, and mostly permanent effect.
The main estimated adverse impacts are related to the risk of collapse/creeping of the built
infrastructure that could potentially affect the soil and water resources on the biophysical setting
and diverse components of the social setting, with an incidence in the OA. These adverse impacts
have been assessed as moderate to high, although they would appear predominantly in the long term
and would be temporary.
Potentially significant impacts to the water quantity and/or quality of the La Plata River are not
expected since the proposed works would not affect the drainage balance of the Vega basin, and the
discharged storm water from the new emissary would be of similar quality as that currently being
discharged by the existing drainage system. The La Plata River has an average yearly flow of
22,000 cubic meters per second, while the new Vega discharge will have a maximum flow of 60
cubic meters per second that would appear around every ten years, and an estimated influence zone
on the river surface up to 200 meters from the coastline—which is seriously compromised by
diverse contaminants presence—. In addition, monitoring activities of the discharge of the
Maldonado drainage system showed that the discharged storm waters improve the water quality of
the receiving body in the influence zone of the discharge. It is foreseen that the same situation will
be verified in the new discharge of the Vega basin.
The highest and permanent positive impact expected of the Operation and Maintenance phase of the
Vega basin’s new drainage tunnel is increased flood protection in the ADI and the associated direct
and indirect benefits on all the compartments of the social setting (population, economic activity,
infrastructure and services, facilities, cultural patrimony, urban movement, territorial structure,
and landscape). These benefits could also reach the AII and even the entire city of Buenos Aires.
Another estimated positive impact is job creation in connection with the operation and maintenance
activities of the new drainage system.


                                                 18
   Secondary and tertiary drainage conduits
The operational phase would have mostly positive effects. In general terms, they would be of high
to medium intensity and would reach the ADI.
Adverse environmental potential impacts would be related to the “risks” of maintenance tasks (e.g.
accidental releases, technical and human failures, extraordinary climatic events). These impacts are
assessed as moderate (medium intensity, with occurrence in the long term, transitory and confined
to the OA).
The operation of the improved secondary and tertiary drainage system will have the main expected
permanent benefits (optimization of the flood protection infrastructure), principally in the ADI and
on all the social compartments. It will also contribute to job creation (maintenance activities).

2.7. ENVIRONMENTAL AND SOCIAL MANAGEMENT PLAN
The ESIA includes an Environmental and Social Management Plan (ESMP). The main purpose of
the Environmental and Social Management Plan is to ensure the implementation of the socio-
environmental mitigation measures and recommendations, and to guarantee the accomplishment of
the proposed quality objectives, from the start of the works to the end of its useful life.
Mitigation measures were designed to prevent, correct, or mitigate the potential environmental and
social impacts generated within the project’s area of influence due to its implementation. The ESIA
summarizes, with the use of datasheets and tables, the diverse potentially impacting actions and
their associated potential impacts (effects and social and/or environmental affected compartments),
and presents a detailed description of the corresponding mitigation measures to be applied. In
addition, the mitigation measures are linked, accordingly, to the specific Technical Specifications
which are part of the project final design and construction Terms of Reference (and will be part of
the corresponding future contract). Mitigation measures charts also contain information on
implementation responsibilities, control responsibilities, and periods/frequencies of application.
Recommendations and mitigation measures for the proper management of the disposal site(s) of
exceeding soil from excavations, including soil disposal conditions, are provided by the ESIA.
Disposal of soil will also require compliance with all applicable regulations.
In addition to the mitigation measures, the project design itself includes particular aspects to help
avoid, minimize or mitigate potential adverse impacts and risk of the works. For example, the
selected methodology, procedures, and constructive tunneling technology (TMB-EPB) accomplish
the excavation while mitigating its own effects by minimizing disruptions on surface, avoiding
alterations on relevant underground infrastructure, and isolating structures from natural materials
(soil and groundwater), all aspects demonstrated in the successful implementation of the APL1. The
decision of having the outlet shaft serve as the tunneling machine’s temporary access during
construction, and abandoning the boring machine shield during the works will also mitigate effects
on the affected community, the urban scene, the territorial structure, and the environment in general.
Other particular design aspects that are targeted to prevent or minimize the potential negative
impacts and risk of the works, also built on the experience acquired from the APL1 implementation,
include i) the use of hydro milling machine to build the outlet shaft (future discharge chamber)
vertical structure, which will reach the underlying rock, method that will allow a minimal
disturbance and the excavation of the shaft under “dry” conditions; ii) foreseen construction
methods and technical provisions, mainly the use of earth pressure balance for tunneling and the use


                                                 19
of hydro milling machine for the discharge chamber walls construction, would avoid an artificial
hydraulic connection between aquifers; and iii) the alignment of the Vega new drainage tunnel and
its complementary works entirely placed under roads and public space/land will minimize risks on
buildings from excavation activities and potential resettlement impacts.
Based on the differences between the construction and operation stages (e.g. type of measures,
responsibilities for implementation), the ESMP has been accordingly divided into two plans, one for
construction and another for Operation and Maintenance (O&M).
Construction ESMP
The ESMP scope covers the works’ Operational Area as well as the direct and indirect areas of
influence. The ESMP defines its general and specific objectives and organizes the mitigation
measures under a set of (interrelated) programs, with particular objectives, requirements, and
execution methodologies. The planning of the required socio-environmental management will allow
an effective and efficient allocation of resources (technical, human, economic) and an appropriate
articulation with the construction schedule. Established programs are the following:
   - Institutional Coordination Program
   - Legal and Institutional Aspects Program
   - Staff Capacity Development and Training Program
   - Occupational Health and Safety Management Program
   - Monitoring and Control Program
   - Contaminated Soil Management Program
   - Trees, Plants and Other Vegetation Removal and/or Replacement Program
   - ESMP Implementation and Quality Control Program
   - Environmental Education Program
   - Communication and Community Participation Program
   - Audits Program
   - Transport and Traffic Environmental Management Program
   - Physical Cultural Resources Protection Program
   - Contingency Program
Some details of several of these programs include the following:
  - The legal and institutional aspects program seeks to ensure compliance with the applicable
    legal framework (extensively described in the ESIA, Chapter 3). This program details the
    required management of the licenses, authorizations, permits, etc. pertinent to the works and
    related activities (timely presentations before the corresponding competent authorities,
    associated administrative / documentation requirements, etc.)
  - The program on staff capacity development and training is targeted towards raising awareness
    among workers, ensuring compliance with requirements and familiarizing them with
    occupational safety and health issues, environmental protection, and emergency procedures,
    among others.
  - The program for occupational health and safety provides guidelines for the appropriate
    protection of worker’s health and safety. It requires an Occupational Health and Safety
    System (OHSAS 18001 Certificate) and compliance with the pertinent legal framework.


                                                20
  - The monitoring and control program provides detailed procedures and a set of indicators that
    should be periodically measured to evaluate the environmental performance of the works (on
    air, soil and groundwater quality, as well as noise and vibrations), identify non-compliances at
    an early stage, and take the appropriate measures.
  - The contaminated management soil program is designed to ensure the appropriate handling,
    transport, treatment and disposal conditions per applicable regulations of contaminated
    excavation materials, facing its potential presence due to, for example, past contamination
    events, leaking underground storage tanks of service stations, etc. Previous to excavation, sites
    with risks of potential contamination will be identified. During excavation, soils will be
    screened for VOCs (using PID devices) and also analyzed for TPH and heavy metals
    presence. Depending on results or particular circumstances, deeper site investigations could be
    implemented. In addition, all soil materials from excavations will be subject to monitoring and
    control measures to determine their quality and the corresponding management requirements.
  - The environmental education program is aimed at increasing the knowledge and awareness of
    stakeholders regarding the social and environmental aspects involved in the construction and
    operation of the hydraulic works in the Vega basin. Activities under this program, which will
    be specifically designed for the diverse particular participants, will include meetings, guided
    field visits, workshops, and seminars, among others.
  - The communication and community participation program is designed to inform the involved
    neighborhoods in an adequate and timely manner about the status of the works
    (implementation schedule, traffic deviations, special warnings, etc.), and to promote
    participation to ensure appropriate interaction and feedback from the main stakeholders of the
    hydraulic works in the Vega basin.
  - The program on trees, plants and other vegetation removal and/or replacement, is aimed to
    protect the flora (natural or planted) in the area affected by the works, minimizing any
    alteration of the existing ecosystem. Removal of vegetation will be restricted to the essential
    construction needs, and will require the previous Supervision and city approvals; these tasks
    will be performed by manual methods. Trees will be always protected, and, if needed and
    possible, moved; the removal of urban trees will need to comply with the applicable regulation
    (Law 3263, on Public Urban Trees Protection), including the competent authority permit. Any
    tree that has to be removed will be replaced by at least other three of the same species.
  - The program for the protection of physical cultural resources is prepared on a precautionary
    basis. An archeologist will be accompanying and supervising, according to applicable
    regulations, the conventional method tunneling and shafts excavation activities. Procedures
    for appropriate management and handling of chance findings are provided.
  - The contingency program is aimed at ensuring sufficient level of preparedness and response
    against emergencies such as extreme natural events, technical or social emergencies, and
    accidents, among others.
In addition to the ESMP, and as mentioned above, several potential negative impacts and risks will
be prevented or mitigated by the application of the best available technologies, and strong works’
technical specifications (design, standards, procedures, etc.) that include the corresponding
mitigation measures/socio-environmental management requirements.
A Resettlement Policy Framework (RPF), according to OP 4.12 on Involuntary Resettlement, was
developed for the Vega Flood Prevention and Drainage Project (P145686), essentially in connection


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with the interventions envisioned under Sub-Component 2.3, in the Cildañez Basin (see ANNEX 1).
The RPF, among other things, identifies the potential resettlement impacts associated to the Project,
and establishes the corresponding mitigation measures. The RPF will be part of the Construction
ESMP of the Hydraulic Works in the Vega Basin project on a precautionary basis, in order to
appropriately address, if needed, any potential impact covered by the policy.
Operation and maintenance ESMP
The O&M ESMP will be based on the ESIA and the construction-phase ESMP. It establishes the
objectives, strategies, criteria, and required procedures to ensure the final objective of the new
drainage system in the Vega basin: protection and safety of the involved population and the
physically-intervened environment, as well as the sustainability of the investments. The ESMP
scope covers the Vega basin area. Pertinent Programs of the previous stage will continue to be
implemented during the O&M phase, adjusting, as needed, the objectives, scopes, and activities to
the new requirements (e.g. Legal and institutional Aspects Program, Monitoring and Control
Program, Communication and Community Participation Program, Contingency Program, among
others).
Responsibilities
The Construction ESPM implementation will be mainly the responsibility of the contractor, who
will appoint a Socio-Environmental Management Coordinator—with adequate qualifications and
experience—and will establish an Environmental Management System under which the ESMP
would be implemented. The contractor will provide the needed resources (human, technical,
economic/budgetary) for the proper implementation of the Construction ESMP. All these
requirements will be included in the construction contract.
During the construction of the Vega new tunnel and complementary works, the contractor will be
supervised by an independent, specialized Supervision Firm, including all the Social,
Environmental, and Health and Safety aspects. The MUD will oversight the execution of the all the
works (tunnel and complementary works as well as secondary and tertiary drainage conduits).
The O&M ESMP implementation will be mainly the responsibility of the operator of the hydraulic
works, which is ultimately in charge of the city’s drainage system operation and maintenance
agency (General Directorate of the Storm Drain System from the Ministry of Environment and
Urban Space). The operator will appoint an Environmental Responsible person—with adequate
qualifications and experience—, to be the leader of the ESMP implementation and the operator
representative before the competent authorities and stakeholders.

3.   PUBLIC CONSULTATIONS
The overall environmental assessment process for the interventions in the three basins involved in
the Vega Flood Prevention and Drainage Project is based on a multi-phase approach: i) the pre-
feasibility studies (finished during the HMP preparation), which analyzed alternatives on the basis
of their technical, socioeconomic, and environmental merits, and ii) a more thorough and updated
environmental assessment for each specific project/work to be developed based upon the HMP.
These actions have been, and continue to be, complemented with dissemination and various forms
of public input/participation. Thus, social and environmental aspects have been taken into account
in each phase of the design for the infrastructure works: from the preliminary ideas to the bidding
stage.

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The definition of the technical aspects and the updated environmental assessment of the works have
incorporated the experience and results of the execution of past projects, including outreach and
participation activities. With this in mind, adjustments to the construction sequence for the new
Vega tunnel are planned (TBM technology application) for with respect to the one originally
proposed in the HMP, which in turn is recommended for high occupancy zones where human
intervention is high. Meanwhile, interventions in the Cildáñez basin are formulated with the purpose
of addressing the current socio-environmental situation and the expectations of the community of
the surrounding area, which are considerably different than those that were current at the time the
HMP was created, for which modifications to the technical approach are required. Previous
implementation experiences and stakeholders input were used to refine the works design and the
Terms of Reference of the related EA studies of the new proposed Project.
The following list summarizes some of the relevant consultation actions carried out by the city
during the environmental assessment process of the Project works for the different basins, from the
time of formulation of the HMP to date.
   Publication of the pre-design reports and meetings and seminars to present the findings, with the
    participation of local and international professionals and experts on the subject, NGOs, neighbors,
    etc. (from 2002 to 2004)
   Publication of the Maldonado Basin Works full EIA (during the APL1 preparation) and
    consultation meetings, including public hearings, with stakeholders to present and further discuss
    the project and its accompanying EIA (December 2004 and June 2005)
   Public hearing for the analysis of modifications to the flood mitigation works for the Maldonado
    basin (APL1, construction phase) and its accompanying EIA (May 2009)
   Implementation of Procedures PSHX-GH-0001 – Outreach to the Community and PSHS-GH-
    0011 – Institutional Coordination of the EMP of the construction phase of the APL1’s drainage
    tunnels for the Maldonado stream (2008 to 2012)
   APL1's Social Impact Study (Irene Novacovksy, World Bank. June, 2012). The total number of
    surveys increased to 600; 400 homes of residents surveyed in the area of Maldonado basin and
    200 completed in homes located in the Vega basin.
   Informative and consultation meetings about the HMP, completed and future hydraulic works
    projects, and the issue of floods that the Ministry of Urban Development conducted in 2013 with
    residents of the city. The following meetings were held:
    - Comuna 10, two meetings in the month of May; Comuna 9, one meeting in April, two in July,
      one in August and one in September. In connection with the Maldonado and Cildáñez basins’
      works.
    - Development Associations of the Parque General Belgrano and Nuevo Belgrano
      neighborhoods, March; Comuna 15, October. In connection with the Vega basin’s works.
   Meetings between the Ministry of Urban Development and the Argentine Society of Engineers.
    (March and November 2013)
   Customer service center for complaints and inquires of the Ministry of Urban Development for
    city residents (contact info, email: mduvecinos@buenosaires.gob.ar; phone: 4323-8000 ext.
    4070). Between May and November 2013, 70 consultations about the works in the Maldonado
    basin and 18 consultations on the works in the Vega basin were received and answered.

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   Meetings that the Ministry of Environment and Public Spaces has held with NGOs, forums, and
    community representatives, particularly from the informal settlements in the surroundings of Lake
    Soldati, Los Piletones and Nueva Esperanza neighborhoods, and other public agencies that work
    in the area (city’s Secretariat of Inclusive Habitat and Buenos Aires Sur Corporation, AySA,
    ACUMAR). August through November 2013.
Consultations on the Hydraulic Works in the Vega Basin project
The specific consultation process on the Hydraulic Works in the Vega Basin project can be
summarized as follows:
 The public consultation process for the Vega hydraulic works project has been carried out from
  the initial stages of the project planning (HMP preparation). First stakeholder input was received
  during the presentation of the basin’s pre-design structural solutions (2002-2004).
   The Terms of Reference of the project advanced design and the ESIA were refined based on
    previous related experiences (particularly, consultation on the ESIA of the APL1’s drainage
    tunnels for the Maldonado stream—2004, 2005 and 2009—and implementation of the Procedures
    Outreach to the Community and Institutional Coordination of the construction phase ESMP of the
    APL1—2008 to 2012—) and various forms of public input/participation carried out during the last
    two years, such us:
    -   APL1’s Social Impact Study (Irene Novacovksy, World Bank. June, 2012). The study
        included a survey in 200 homes located in the Vega basin.
    -   Informative and consultation meetings with neighborhood associations and representatives of
        the involved Comunas (Development Associations of the Parque General Belgrano and
        Nuevo Belgrano neighborhoods, March 2013; Comuna 15, October 2013)
    -   Customer service center for complaints and inquires of the Ministry of Urban Development
        for city residents (contact info, email: mduvecinos@buenosaires.gob.ar; phone: 4323-8000
        ext. 4070). Between May and November 2013, 18 consultations on the works in the Vega
        basin were received and answered.
The main issues that were raised in these diverse forms of public input/participation can be
summarized as follows (i) ensuring strong technical designs for the hydraulic infrastructure to reach
the objective of flood mitigation; (ii) ensuring structures totally isolated from underground
materials, in particular avoiding any cross contamination between aquifers derived from the works;
(iii) high expectations of the Vega basin inhabitants on a prompt implementation of the projected
works; and (iv) emphasis on implementing non-structural measures along with the hydraulic
infrastructure. As it is described in several previous sections of this Executive Summary, pertinent
issues from public input have been incorporated into the Hydraulic Works in the Vega Basin design
and in the corresponding ESIA and ESMP. From its part, the proposed Vega Flood Prevention and
Drainage Project (P145686) would prioritize the implementation of Component 1 (non-structural
measures) and Sub-Component 2.1 (Hydraulic Works in the Vega Basin).
A preliminary/advance report of the ESIA of the Hydraulic Works in the Vega Basin was disclosed
to the public through the Autonomous City of Buenos Aires’ Website on December 27, 2013. The
corresponding draft report was published in the same Website on March 14, 2014,
(http://www.buenosaires.gob.ar/desarrollourbano/grandesobras/obrashidraulicas/cuenca-arroyo-
vega), and in the World Bank’s InfoShop Website on April 9, 2014.


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A specific public consultation on the ESIA of the Hydraulic Works in the Vega Basin and
associated ESMP, according to Bank’s policies, is foreseen to take place in April 2014. In addition,
the ESIA will be subject to a Public Hearing according to local regulations. The final ESIA will
incorporate the results of the consultations, taking into account the stakeholders’ input.
The required ongoing consultation on the ESMP during the final design and construction stages will
be implemented through the established Communication and Community Participation Program,
described above.
In respect to queries, complaints and disputes that could come up as a result of the complexities of
the proposed Vega Flood Prevention and Drainage Project’s investments, the City of Buenos Aires
will strengthen its current claims management system and a robust grievance and redress
mechanism to manage Project related information requests, complaints and grievances as well as to
solve disputes will be put in place. This mechanism will include addressing and registering
complaints at the site of the conflict by contractors or at the closest office of the Government of the
City of Buenos Aires (the city has 15 local offices, each one in the respective Comuna, named
centros comunales), which will be referred to the MUD. As mentioned above, the MUD has already
a customer service center for questions and complaints for city residents, and also has a positive
experience about disseminating information on civil works regularly by means of leaflets, meetings
and workshops with local residents and community organizations, which contributes to diminish the
opposition to works. The MUD will broaden and improve its current capacities and will articulate
institutional responsibilities with the UMF to solve claims in the city’s internal instance
(administrative). Citizens will be also informed on the three external instances where complaints
could be posed when they are not comfortable with city’s response, which are mediation, the
intervention of the Ombudsman, and an appeal before Justice. In order to attend to claims and solve
conflicts, and once every effort in the administrative instance has been made, the alternative
voluntary procedures for the solution (mediation) will be promoted previously to the judicial
instances.
The specific procedures and institutional responsibilities applicable to the internal instance
(administrative) and to the mediation will be developed in the Operation Manual of the Project,
which will be finalized before the beginning of the Project implementation.
The main elements of the grievance and redress mechanism, the related processes and timeframes as
well as the responsibilities pertinent to UMF/MUD, the mediator and the claimer will be designed
according to the different stages of the works implementation, and also to the local context and
socio-cultural characteristics of the groups involved or potentially affected by the Project.




                                                  25
                                               ANNEX 1

A summary of expected potential impacts for Sub-component 2.2 and Sub-component 2.3, and of
the instruments and plans developed for their proper management, are described below.
   Sub-Component 2.2 - Maldonado basin: This Sub-component will complete the network of
    secondary and tertiary drainage conduits planned for the basin in the HMP. These works were
    included in the executive project of the two large tunnels successfully executed under the
    previous Bank funded Urban Flood Prevention and Drainage Project APL1. Therefore, they were
    part of the Project’s Environmental Impact Assessment – EIA developed in 2005 following
    Bank’s guidelines and requirements as well as local regulations.
    To date, the city has built about 28 percent of the network. The remaining 33 kilometers,
    distributed throughout many different sectors of the basin—which has a surface area within the
    city of about 5100 hectares—is proposed to be partially financed by the new Project. Part of
    these conduits will feed water directly into the large drainage tunnels built under the APL1, while
    another portion will enhance the flowing capacity from the Maldonado upper basin that is
    diverted into the Cildáñez basin.
    For the management of impacts related to this Sub-component, the EIA of the Maldonado’s
    secondary and tertiary drainage conduits originally developed for the APL1 has been updated.
    The new Environmental and Social Impact Assessment – ESIA presents updated baseline
    secondary information on socio-environmental aspects of the Maldonado basin, as well as
    detailed relevant current data on the specific sites where the conduits will be built (blocks and
    corresponding operational surroundings): predominant urban land use, existing public
    transportation services, traffic flows, relevant sectors or buildings presence (squares, schools,
    hospitals, churches, etc.), among others. The ESIA addresses environmental and social impacts,
    risks, and benefits, and includes an Environmental and Social Management Plan – ESMP.
    The main potential adverse impacts on the urban socio-environmental setting are related to the
    construction phase. They include noise; vibration; exhaust machinery; dust emission and
    dispersion from excavation activities; disruptions in normal urban movement (traffic and
    pedestrian); and safety issues. Potential impacts on cultural resources due to soil movements
    have also been considered. None of these potential impacts is anticipated to be significant. No
    resettlement related impact has been identified for the project. The creation of jobs is the main
    positive impact expected from the construction stage. The operational phase would have mostly
    positive effects: permanent social benefits with the optimization of the basin’s flood protection
    infrastructure; undesirable impacts would basically be related to maintenance activities (e.g.
    conduits obstructions).
    A set of mitigation measures was identified and designed for the proper management of works,
    covering the following aspects: handling and transport of materials, traffic, camps and ancillary
    facilities, protection of urban trees, demolition and restoration of road surface and sidewalks, soil
    excavation and movement, removal of existing facilities, drainage of water, effluents, debris and
    other solid waste generation, atmospheric emissions and particulate matter, noise and vibration,
    interferences with service infrastructure, cultural resources chance finds.
    The ESMP organizes such measures and determines, for their appropriate implementation, the
    following programs: Impact Prevention and Mitigation Program; Occupational Health and Safety

                                                   26
    Management Program; Environmental Authorizations and Permits Management Program; Staff
    Capacity Development and Training Program; Monitoring and Control (air, soil, and water
    quality) Program; Cultural Resources Protection Program; Communication, Community
    Participation and Complaint Program; Audits Program; Contingencies Program; and ESMP
    Implementation and Quality Control Program.
    The updated ESIA was developed taking into account the requirements of the World Bank
    Safeguard Policies and the Autonomous City of Buenos Aires’ legal framework on
    Environmental Impact Assessment.
    As mentioned above, the Maldonado’s secondary and tertiary drainage conduits to be built under
    the new Vega Flood Prevention and Drainage Project were part of the original executive project
    of the hydraulic works in Maldonado basin and, accordingly, of the project’s EIA developed in
    2005 following Bank’s requirements and local regulations. In that sense the projected works
    under Sub-component 2.2 are following the requirements of the local EIA legal system; the city’s
    Environmental Authority has recently awarded the extension (renewal) of the environmental
    permit for the execution of the works to the MUD (February 24, 2014).
   Sub-Component 2.3 - Cildáñez basin: The “Program for Integrated urban water management in
    marginal areas of the Maldonado-Cildañez Basin” will be implemented under this Sub-
    component. The Cildañez basin covers a suburban area of around 3100 hectares in the southern
    part of the city of Buenos Aires.
    The Program’s general objective is to improve the existing drainage infrastructure to reduce the
    likelihood of flooding and promote better life conditions in a low-income area within the basin.
    The influence zone of the Program—about 350 hectares—is one of the most socially vulnerable
    areas of the city. It comprises a population of around 50,000 inhabitants who live precariously in
    the surroundings of Lake Soldati. Lake Soldati is actually a pond, a depressed area located in the
    low basin. This lake is connected to the culverted Cildañez stream that in turn receives a
    diversion flow (up to 100 cubic meters per second) from the Maldonado drainage system. During
    heavy storm events the Cildañez stream floods the lake area. The Cildáñez stream flows to the
    Riachuelo River. Now the lake area is environmentally degraded due to the discharge of
    wastewater from the informal settlements and the dumping of solid waste.
    Expected benefits from the implementation of the Program include flood mitigation, betterment
    of sanitation conditions for the people that live near Lake Soldati, and environmental and urban
    improvement of the area.
    Foreseen works and complementary interventions to be implemented under this Sub-component
    are aimed at i) the environmental recovery of Lake Soldati by removing solid waste, and
    collecting and diverting both sewage and storm run-off currently discharging into the lake; ii) the
    use of this lake as a permanent flood retention/equalization reservoir to delay flows to the
    Riachuelo River; iii) the improvement of the precarious drainage and wastewater collection
    networks in the low-income neighborhoods and informal settlements located near the lake; iv)
    the segregation of the water flows of the Maldonado upper watershed from those of the Cildáñez
    watershed; and, v) the enhancement of the urban public space in Lake Soldati surroundings.
    The specific different physical interventions, structured as sub-projects, will be fully defined and
    designed during Project implementation to accurately determine needed actions and associated



                                                   27
  details, secure the pertinent inter-institutional agreements and commitments, and properly
  integrate the local community’s input.
  Anticipated potential adverse impacts related to activities of Sub-component 2.3 are similar to
  those of Sub-component 2.2, since small to medium sized-scale infrastructure works in urbanized
  areas will take place. In addition, civil works involved in sub-projects may affect a small number
  of houses in the informal settlements, although the exact impacts or their zone of influence will
  not be identified by Project appraisal. Therefore, a Resettlement Policy Framework has been
  prepared for the Vega Flood Prevention and Drainage Project according to the requirements of
  the World Bank operational policy 4.12 on Involuntary Resettlement, in order to appropriately
  address, if needed, any potential impact covered by the policy. If any civil works causes
  resettlement, a Resettlement Action Plan will be prepared prior to the start of the works.
  For the management of impacts related to this Sub-component, an Environmental and Social
  Management Framework – ESMF has been developed based on World Bank safeguard polices.
  The ESMF, among other things, (i) presents a project overview (the context of the Vega Flood
  Prevention and Drainage Project and the particular aspects of the “Program for Integrated urban
  water management in marginal areas of the Maldonado-Cildañez Basin”; (ii) summarizes the bio-
  physical environment and socio-economic baseline of the Program-affected people in the
  Program influence zone; (iii) describes the pertinent institutional and legal framework and World
  Bank policies requirements for works of the type considered under the Program; (iv) defines
  responsibilities for the environmental and social management of the Program; (v) identifies the
  type of potential environmental and social impacts based on the foreseen physical interventions
  and site characteristics, and the corresponding mitigation measures; (vi) establishes guidelines
  and procedures for the proper social and environmental management of the Program’s sub-
  projects along the project cycle (including sub-projects’ eligibility and screening, identification
  of applicable legal requirements, and consultation activities); (vii) establishes the requirements
  for the monitoring of the implementation of sub-projects and of the overall socio-environmental
  management of the Program; and (vii) includes a Resettlement Policy Framework, which has
  been incorporated into the ESMF as Annex 2.
  Foreseen works and complementary interventions in the Cildáñez basin do not anticipate any
  significant negative impact on physical cultural resources; however, any environmental analyses,
  as part of the ESMF, will specifically include consideration of physical cultural resources. All
  sub-project ESMP and related construction contracts will include procedures and requirements
  related to chance find management.
Preliminary/advance reports of the ESIA of Sub-component 2.2 and of the ESMF of Sub-
component 2.3 (without its Annex 2), were disclosed to the public through the Autonomous City of
Buenos Aires’ Website on December 27, 2013. The corresponding draft reports were published in
the same Website on March 14 and in the World Bank’s InfoShop Website on April 9, 2014.
The draft RPF is in the process of being disclosed to the public and published in the World Bank’s
InfoShop Website.
Specific public consultations on the aforementioned draft instruments, according to Bank’s policies,
are foreseen to take place in April 2014. The final versions will incorporate the results of the
corresponding consultations, taking into account the stakeholders’ input.



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