Learning from Japan’s Experience in Integrated Urban Flood Risk Management: A Series of Knowledge Notes Knowledge Note 4: Operating and Maintaining Urban Flood Risk Management Investments ©2019 The World Bank International Bank for Reconstruction and Development The World Bank Group 1818 H Street NW, Washington, DC 20433 USA October 2019 DISCLAIMER This work is a product of the staff of The World Bank with external contributions. The findings, interpretations, and conclusions expressed in this work do not necessarily reflect the views of The World Bank, its Board of Executive Directors, or the governments they represent. The World Bank does not guarantee the accuracy of the data included in this work. The boundaries, colors, denominations, and other information shown on any map in this work do not imply any judgment on the part of The World Bank concerning the legal status of any territory or the endorsement or acceptance of such boundaries. 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World Bank. 2019. “Learning from Japan’s Experience in Integrated Urban Flood Risk Management: A Series of Knowledge Notes—Knowledge Note 1: Assessing and Communicating Urban Flood Risk.” World Bank, Washington, D.C. World Bank. 2019. “Learning from Japan’s Experience in Integrated Urban Flood Risk Management: A Series of Knowledge Notes—Knowledge Note 2: Planning and Prioritizing Urban Flood Risk Management Investments.” World Bank, Washington, D.C. World Bank. 2019. “Learning from Japan’s Experience in Integrated Urban Flood Risk Management: A Series of Knowledge Notes—Knowledge Note 3: Designing and Implementing Urban Flood Risk Management Investments.” World Bank, Washington, D.C. World Bank. 2019. “Learning from Japan’s Experience in Integrated Urban Flood Risk Management: A Series of Knowledge Notes—Knowledge Note 4: Operating and Maintaining Urban Flood Risk Management Investments.” World Bank, Washington, D.C. World Bank. 2019. “Learning from Japan’s Experience in Integrated Urban Flood Risk Management: A Series of Knowledge Notes—Appendix: Case Studies in Integrated Urban Flood Risk Management in Japan.” World Bank, Washington, D.C. Knowledge Note 4: Operating and Maintaining Urban Flood Risk Management Investments i ACKNOWLEDGEMENTS The four-part series “Learning from Japan’s Experience in Integrated Urban Flood Risk Management: A Series of Knowledge Notes” was prepared by a World Bank team led by Jolanta Kryspin-Watson, and comprising Shoko Takemoto, Zuzana Stanton-Geddes, Kenya Endo, and Masatsugu Takamatsu. Primary and secondary data gathering, and research, was conducted by Washington CORE and Yachiyo Engineering Co., Ltd. The four reports benefited from additional research and contributions by Jia Wen Hoe, Sayaka Yoda, Toshihiro Sonoda, Alex Keeley, Tomoki Takebayashi, Thimali Thanuja Pathirana Batuwita Pathiranage, and Chinami Yamagami; and peer review by Vivien Deparday, Keiko Saito, Ryoji Takahashi, Bontje Marie Zangerling, Srinivasa Rao Podipireddy, Dixi Mengote-Quah, Dzung Huy Nguyen, and Camilo Lombana Cordoba. The team is also grateful for the support of Mika Iwasaki, Luis Tineo, Reiko Udagawa, and Haruko Nakamatsu. The Knowledge Notes were developed with valuable contributions and guidance from numerous Japanese professionals and experts on integrated urban flood risk management. These include Professor Hiroaki Furumai, the University of Tokyo; Arata Ichihashi, Tokyo Metropolitan Research Institute for Environmental Protection; Michiru Sasagawa, Rain City Support and People for Rainwater; Nobuyuki Tsuchiya, Japan Riverfront Research Center; Shinji Nishimura, Urban Renaissance Agency (UR); Keiji Takeda, UR; Mikio Ishiwatari, Japan International Cooperation Agency (JICA); Miki Inaoka, JICA; Tomoki Matsumura, Ministry of Land, Infrastructure, Transport and Tourism (MLIT); Akito Kinoshita, MLIT; Takuji Nakazato; Chikao Okuda, Tokyo Metropolitan Government; Professor Takanori Fukuoka, Tokyo University of Agriculture; Yorikazu Kitae, Development Bank of Japan (DBJ); Tomohiro Ishii, Yokohama City; Minato-Mirai 21 Promotion Division, Urban Development Bureau, Yokohama City; Environmental Planning Bureau, Yokohama City; and Shoji Takemoto, Kobe City. Editorial services were provided by Fayre Makeig and Lisa Ferraro Parmelee. Kenya Endo designed the report. The Knowledge Notes were prepared under the auspices of the Urban Floods Community of Practice (UFCOP). UFCOP is a global knowledge initiative led by the World Bank with support from the Global Facility for Disaster Reduction and Recovery (GFDRR) and others. The Knowledge Notes were developed with the financial support of the Japan–World Bank Program for Mainstreaming Disaster Risk Management in Developing Countries, which is financed by the Government of Japan and receives technical support from the World Bank Tokyo Disaster Risk Management Hub. Cover Image: Futakotamagawa Rise and Park in Setagaya Ward, Tokyo—a multipurpose, public, pr ivate, and community-led urban redevelopment project that integrates nature-based solutions to mitigate river and surface water flooding. (Photo Credit: Kenya Endo) Learning from Japan’s Experience in Integrated Urban Flood Risk Management Knowledge Note 4: Operating and Maintaining Urban Flood Risk Management Investments ii Development of Knowledge Notes: The Japanese Experience in Integrated Urban Flood Risk Management Draft Knowledge Notes Knowledge Note 2: Urban Flood Risk Investment Planning and Prioritization Table of Contents 1. Summary 1 2. O&M of Urban Flood Risk Management Investments 2 2.1 Institutional Framework for O&M 2 2.2 Planning and Implementation of O&M Activities 4 2.3 Performance Monitoring and Evaluation 6 3. Enabling Factors for Effective O&M 11 3.1 Guidelines and Manuals 12 3.2 Monitoring and Management Plans 14 3.3 Stakeholder Collaboration and Engagement 14 Sharing O&M Costs and Responsibilities with the Public Sector 15 Sharing O&M Costs and Responsibilities with the Private Sector 16 Sharing O&M Costs and Responsibilities with Community Members 19 3.4 Innovative O&M Technologies 20 4. Lessons Learned and Key Takeaways 22 5. References 23 Learning from Japan’s Experience in Integrated Urban Flood Risk Management Knowledge Note 4: Operating and Maintaining Urban Flood Risk Management Investments iii List of Figures Figure 1. Entities Responsible for the O&M of Urban Flood Risk Management Investments in Japan 3 Figure 2. Overview of Asset and Stock Management 4 Figure 3. Life-Cycle Cost Savings Due to Careful Management of Sewerage System Assets in Tokyo’s 23 Central Wards 5 Figure 4. Private Sector Participation in Sewerage Projects in Japan 16 Figure 5. Concession Project Scheme for Hamamatsu City’s Sewerage System 18 Figure 6. Sharing Responsibility for the Development and O&M of the Futakotamagawa Rise and Futakotamagawa Park Project 19 List of Tables Table 1. Enabling Factors, Tools, and Approaches for Effective O&M 11 Table 2. Manuals and Guidelines for O&M, Monitoring, and Evaluation, by Flood and Investment Type 13 Table 3. Utilization of Advanced Technology and Data in the Field of Maintenance and Management in Japan 21 List of Boxes Box 1: Monitoring and Evaluating the Impact of Flood Risk Management in Two Urban Housing Development Initiatives 7 Figure B1.1. Monitoring and Evaluation Area at Akishima Tsutsujigaoka Collective Housing Figure B1.2. Impact of the Stormwater Infiltration System in Akishima Tsutsujigaoka Collective Housing Figure B1.3. Monitoring and Evaluation Area at Hachioji Minamino City Figure B1.4. A Comparison of Annual Water Balance before and after Stormwater Storage and Infiltration Measures Box 2: Budgeting for O&M: Financial Resources Allocated to the O&M of River and Sewerage Facilities in TMG 15 Figure B2.1. Financial Resources Allocated to the O&M of River and Sewerage Facilities, FY 2016 Learning from Japan’s Experience in Integrated Urban Flood Risk Management Knowledge Note 4: Operating and Maintaining Urban Flood Risk Management Investments 1 1. Summary Operation and maintenance (O&M) are critical to ensuring the effectiveness of urban flood management investments over time. In the context of human and financial resource constraints, Japanese cities must enhance O&M to extend the functional lifetimes of critical investments. While these cities have been able to mobilize financial and technical resources needed to design and implement a wide range of flood management investments (as described in Knowledge Note 3), today many are faced with a large stock of aging infrastructure that was developed during the rapid urbanization of the 1950s–1960s. As Japan’s population shrinks and labor costs increase, there is an urgent need to improve the quality and efficiency of O&M for existing as well as newly developed urban flood risk management investments. This Knowledge Note highlights the Japanese practice of using O&M to sustain and enhance the functionality and efficacy of urban flood risk management investments. This Note focuses on two phases of O&M practice in Japan namely: (i) planning and implementation, such as regular inspections, maintenance, repairs, and replacement work; and (ii) performance monitoring and evaluation, such as regular performance reviews and analysis of data on assets and related indicators. Japanese cities have accumulated various lessons and good practices in how to improve the sustainability and effectiveness of their integrated urban flood risk management (IUFRM) investments. Based on a review of O&M efforts across several Japanese cities (see appendix for a full list), this Note summarizes: (i) key approaches to the O&M of urban flood risk management investments in Japan, and (ii) enabling factors, including various tools and measures that may be used to improve the effectiveness and efficiency of O&M. Based on the Japanese context and lessons learned, key considerations that support the effective O&M of flood management investments include the following: • A policy and institutional framework that outlines the required O&M approach and activities for a facility, key performance indicators, monitoring and evaluation mechanisms, as well as the roles and responsibilities of various stakeholders • Human resources with appropriate knowledge and skills to implement O&M plans and procedures, and technical expertise and ability • An investment design that takes into consideration O&M requirements and their ease of implementation; • Financial resources to carry out O&M activities, and cover the costs of required repairs, replacement, personnel, training as well as research and development of new technologies to enhance flood management and O&M Japanese cities are using various tools and measures to perform effective O&M. This Note highlights some of the key ones: • Technical guidelines and manuals for the O&M of flood management facilities have been developed by the national government (Ministry of Land, Infrastructure, Transport and Tourism, MLIT) and technical institutes (i.e., Japan Institute for Wastewater Engineering and Technology, Japan Sewer Collecting System Maintenance Association, etc.). These documents clarify the institutional roles and help to ensure that technical standards for various types of flood management investments are clearly defined, monitored, and met over time so that these investments fulfill their intended functions and objectives. Given that there are a variety of flood risks, and associated measures are implemented by a diverse range of stakeholders in Japan, using a variety of methods, the public sector, as well as technical institutes and professional associations, play a key role in consolidating the knowledge and expertise available, reviewing and screening the approaches, and sharing recommended guidelines and approaches required for effective O&M. • Monitoring and management plans have been developed and implemented by facility owners. Well-established schedules, stakeholder roles and responsibilities; mechanisms and measures for replacement, repairs, evaluation, budgets, and monitoring; and management plans help facility owners operationalize necessary O&M activities throughout the lifetime of an investment. Asset management databases are often developed and utilized to gather, analyze, and evaluate performance indicators over time. Learning from Japan’s Experience in Integrated Urban Flood Risk Management Knowledge Note 4: Operating and Maintaining Urban Flood Risk Management Investments 2 • The engagement of various stakeholders enables the sharing of roles, responsibilities, and financing for O&M. New ways of designing projects and updating the policy and legal framework to clarify and enable private sector and community engagement in the O&M of flood management facilities are emerging alongside the development of multipurpose and multifunctional flood risk management investments. Key steps include establishing legal frameworks at the municipal level for public-private partnerships (PPPs) and private finance initiatives (PFIs),1 as well as coordinating urban development and the process of upgrading flood risk management facilities, and sharing various roles and responsibilities. Enhanced community participation can also lead to improved awareness and the better management of flood management infrastructure. • Innovative O&M technologies are being used to implement O&M activities more efficiently and effectively, minimizing the time and other resources needed for O&M during the lifetime of an investment. Regular local activities, such as seasonal community cleanup efforts, as well as community-based rainwater harvesting and management groups can enable the access to information, resources, and support necessary to ensure not only the uptake of urban flood management investments but also the O&M and long-term sustainability of these initiatives. 2. O&M of Urban Flood Risk Management Investments Japanese cities today face the challenge of maintaining the effective operation of their extensive yet aging flood risk management infrastructure. For example, in 2016, MLIT reported that out of the approximately 470,000 kilometers (km) of sewerage pipes that service cities across Japan, approximately 14,000 km (3 percent of the total length) were older than 50 years (MLIT n.d.[b]). The share of pipes older than 50 years is projected to increase to 57,000 km (12 percent) by 2026, and 140,000 km (30 percent) by 2036. Additionally, in 2016, out of 1,500 stormwater pumping stations, more than 1,200 stations (77 percent) were reported to have been in operation for more than 20 years. Considering the condition of their infrastructure, Japanese cities need to implement long-term O&M to sustain effective flood risk management functions. While this is particularly true for Japan and relevant to other developed economies with mature infrastructure, lessons learned from Japan can also inform the efforts of developing countries, particularly as they seek to improve the life-cycle design of their infrastructure. 2.1 Institutional Framework for O&M With a common goal of mitigating urban flood risk, Japan’s national and local governments, private sector, and citizens share responsibility for the O&M needed to sustain IUFRM investments. Institutional roles and responsibilities for specific O&M tasks are delegated based on the context, including the roles of facility managers, required expertise, and technologies. In some cases, an O&M management agreement between stakeholders and related organizations is signed before O&M begins. In general terms, prefectures and municipal governments are responsible for installing stormwater storage and infiltration facilities and conducting related O&M in areas under their respective jurisdiction.2 The location, scale, and function of investments, and the requirements for technical knowledge may also inform which entity will most effectively and efficiently lead the O&M of flood management investments. To ensure efficiency, organizations and personnel with the appropriate expertise, knowledge, and skills need to be encouraged to engage. For example, small-scale, decentralized rainwater harvesting systems and rain gardens may be best operated and maintained by community groups or households, supported by training in the required knowledge and skills. On the other hand, large-scale gray infrastructure, such as embankments and extensive underground drainage pipe systems, require specialized knowledge and authorization, as well as substantial financing best suited for the public sector to lead. Further, and as in other countries, for larger structural initiatives, responsibilities can often be transferred from the national government to local governments between the construction and O&M periods. Figure 1 provides an overview of the responsible entities for each flood and investment type. This is followed by 1 Since 1999, Japan has enacted the “Act on Promotion of Private Finance Initiatives” and promoted initiatives to crowd in private finance in partnership with public sector initiatives (Cabinet Office of Japan n.d.). 2 Refer to Knowledge Note 2, Table 1, for an overview of institutional responsibilities across different phases of urban flood risk management. Learning from Japan’s Experience in Integrated Urban Flood Risk Management Knowledge Note 4: Operating and Maintaining Urban Flood Risk Management Investments 3 Figure 1: Entities Responsible for the O&M of Urban Flood Risk Management Investments in Japan Flood type Investment Responsible entity River ood River embankments Underground river over ow Reservoirs, detention parks, management facilities (cisterns, and ponds channels, etc.) Surface ood Underground stormwater management Sewerage treatment facility facilities (cisterns, channels, drainage improvement pipes, culverts, etc.) Stormwater detention ponds, parks, and gardens Rainwater harvesting systems Increasing surface (collection systems and storage permeability (green spaces, tanks installed in public, pervious pavers, and commercial, community buildings) in ltration trenches, etc.) Storm surge ood Seawalls and gates Ground raising Combined / All Risk assessment, land use plans, zoning, and building codes Enhancing early warning systems Improving evacuation, drills, and awareness raising National government Municipal government Facility manager (public or private) Community Sources: Authors’ compilation. Flood Type Investment Type Key Guidelines and Manuals for Operation, Maintenance, Published by Stormwater detention ponds, parks, and gardens Municipal government, facility manager (public or private) and/or community Note 4: Operating KnowledgeSurface ood Sewerage and Maintaining treatment Urban facilityFlood Risk Management Municipal improvement government and/or facility manager 4 Investments Rainwater harvesting systems (collection system a discussion of the two phases of O&M—(i) and storage planning tanks installed and in public, implementation commercial, and Facility (ii) performance manager monitoring (public or private) and and/or community evaluation—and the institutional arrangements in place for them. community buildings) Enhancement of in ltration surface (green space, 2.2 Planning and Implementation pervious pavers and in O&M of Activities ltration trench, etc.) Facility manager (public or private) and/or community In Japan, approaches to the management of assets and stock are included in long-term infrastructure plans that Seawalls and gates MLIT and/or municipal government effective supportStorm surge operations ood with limited human, material, and financial resources. The national government provides policy, technical support, and guidance, and sets standards for O&M. Facility managers, including local government agencies and private Ground sector stakeholders, own, operate, and raising MLITmaintain investments and/or municipal on a day-to-day government basis. For example, to promote the management of assets in sewerage investments, MLIT has developed various policy instruments such as the New Sewerage Vision (2014), Revised Sewerage Act (2015), and Stock Management Risk assessment, landuse plans, zoning and Support Mechanism (2016). In line Municipal with these national policies, financial government and technical assistance is provided to building codes facility managers to support effective O&M (MLIT n.d.[a]). Figure 1 outlines the entities responsible for the various urban flood risk management Combined / All investments Enhancing implemented early warning systems in Japan. As defined by MLIT, Municipal the management government, of a facility’s communities assets and stock encompasses the financial and human resources required for O&M (see figure 2 for a conceptual Improving evacuation, diagram) and enables sustainable, drills, efficient, and and awareness strategic operations by defining clear goals based on an objective raising Municipal government, communities analysis and evaluation of the entire system. Figure 2: Overview of Asset and Stock Management Asset Management Management of stock, nances and human resources Stock management Development of asset database by Management of facility assets referring to • De ning clear goals • Speci cations • Understanding the overall cost • Inspection and monitoring results • Establishment of plan • Implementing repair and renewal works Financial management • Mid- to long-term nancial planning Human resource management • Personnel management • Education and training program • Technical support system Source: MLIT n.d.(a). For example, for sewerage facilities, managing assets would entail examining the entire life cycle of facilities and equipment so that preventative maintenance can be implemented strategically from the planning and design stages. Property is maintained systematically and efficiently while considering the life-cycle costs and harmonizing operations with Enabling medium- Factors Description activities. Projected operations are based on the useful to long-term restructuring for O&M economic life of a facility, or the number of years the facility can be operated for a minimal annual cost, calculated Policy and institutional ameworks Having clear and e ective governance mechanisms and policy incentives for O&M by dividing the outline thetotal (that cost O&M required is, the life-cycle approach cost, such as including regulations, construction subsidies, O&M) by the and management assistance, number of agreements, years etc. of are needed and Properly operation. activities, maintained key performance to ensure will sewerage facilities have e ective andlonger life regular cycles O&M. than Public, theirand private, estimated service community lives all stakeholders and canindicators, be reconstructed monitoringmore evaluation have a signi cant role to play in promoting e cient and sustainable O&M mechanisms and efficiently. mechanisms, as well as the O&M roles for IUFRM investments. and responsibilities of various For example, gure 6 provides and example from the implementation of the Futako- stakeholders tamagawa Rise and Futakotamagawa Park Project, where O&M responsibilities were shared between the government, private developers, tenants, and community mem- bers, Learning from Japan’s Experience in Integrated Urban through Flood a combination of policy incentives and collaboration. Risk Management Tools and Approaches construction work of the Seien district sewerage treatment plant and 2 pumping Renovation cost stations) (owned by the city) Maintenance / Daily work Remarks: ・Sewer pipes are out of concession scope because it is more e cient for city to Knowledge Note 4: Operating and Maintaining Urban Flood Risk Management Investments manage them collectively with other 5 100% covered by Delegation of service districts. users’ service fee fee collection ・Daily work and renovation are outsourced to private contractors by The MLIT’s guidelines for managing the O&M of flood risk management investments public procurement. in Japan include the following steps: State subsidy for • Gather information Renovation on facilities / Renewal Monitoring replacement cost • Decide the priorities for inspection and repair and maintenance work • Set performance targets for facility management, including both repair and replacement work Prefecture 10% covered by • Model long-term repair users’ service fee and replacement scenarios that allow planners to compare various conditions and management methods • Conduct regular inspections and maintenance according to set standards and in line with plans (target facility, 90% covered by extend City scope, measures toHamamatsu facilities’ lifetime, schedules, costs, etc.) • Periodically evaluate plans and approaches, and adjust them as needed * Hamamatsu Water Symphony Co., Ltd. established by six companies, including Veolia Japan. The Tokyo Metropolitan Government (TMG3) is implementing proactive O&M of its extensive and aging sewerage facilities, using the asset management methods described above across its 23 central wards. TMG, together with MLIT, is working to extend the service life of Tokyo’s sewerage systems from their design life of 50 years to 80 years (Bureau of Sewerage, TMG 2017). To this end, it is implementing cost-effective repair and reconstruction Private development Public work in partnership with various sectors and stakeholders. A comprehensive and regularly updated asset database helps monitor progress against TMG’s business plan and is instrumental in prioritizing and implementing Deregulations of height required O&M work on the 16,000 km sewerage network. restrictions and oor Theratio databaseIntegrated includes design of public on pipe locations, information park and private walk space depths, installation years, and types. This largePro settof geospatial information is complemented by monitoring and facility (Apartment, commercial) inspection data, as well as plans for the renewal of aging sewerageSidewalk (Morikawa facilitiesBridge New2018). By monitoring public park Road the degree of deterioration at each facility, for example, TMG can allocate appropriate time and financial resources to reconstruction work. As a result, the life cycle of facilities has been extended, and unnecessary remodeling has been reduced, lowering O&M costs and thus increasing the cost-efficiency of O&M. For example, as shown in figure 3, Partially subsidizing Government: by planning repairs more MLIT, efficiently, TMG, and Setagaya Wardthe annualDeregulation average life-cycle cost O&Mhas been reduced activities Lead byconstruction and O&M (from about 20 percent ¥290 million/year to ¥240 million/year, or $2.5 million/year to $2.1 million/year). Further information on TMG’s Private developers and landowners: Lead construction and O&M management of of the members its thesewerage redevelopmentassets is included in the association appendix (case 16). Coordination Participation in O&M Tenants and community members ー activities ー Figure 3: Life-Cycle Cost Savings Due to Careful Management of Sewerage System Assets in Tokyo’s 23 Central Wards Construction Reconstruction Ad hoc maintenance Cost Average lifecycle cost per annum ¥290 million ($2.5 million) 0 10 20 Year Construction Reconstruction Planned maintenance ¥240 million ($2.1 million) Cost 0 10 20 25 Year Sources: Bureau of Sewerage, TMG 2016b. Learning from Japan’s Experience in Integrated Urban Flood Risk Management Knowledge Note 4: Operating and Maintaining Urban Flood Risk Management Investments 6 2.3 Performance Monitoring and Evaluation Performance monitoring and evaluation processes are critical to help to track the effectiveness of investments in relation to their long-term flood risk management capacities and functions. In Japan, these processes are specific to each type of flood risk management investment. Facility managers typically follow guidelines developed by MLIT, municipal governments, and/or technical agencies. The various types of guidelines developed for different flood risk management investments are described in section 4.1. While the specific processes and criteria for monitoring and evaluation vary between investments, in general: • Performance monitoring includes the (i) identification of expected performance levels during design, and (ii) regular and consistent gathering of data to be used as performance indicators. • Evaluation involves (i) analysis of results against the target, (ii) identification of problems and corrective measures as needed, and (iii) updating of O&M plans and other key facility operation and management frameworks. In 2010, MLIT established detailed draft guidelines for monitoring and evaluating the performance of stormwater infiltration facilities (MLIT 2010). These include ways to calculate stormwater infiltration estimates, review and update facilities’ infiltration capacity by analyzing collected data and simulation models, incorporate quantitative information in planning processes, implement effective O&M, and conduct monitoring and evaluation. Similarly, MLIT has outlined the basic principles and key elements of monitoring river embankments (MLIT 2004). The function of an embankment is to mitigate water penetration and erosion. This monitoring is generally undertaken to (i) identify and observe locations in critical need of attention, and (ii) assess the performance of fortification technologies. Facility managers then gather and organize this information and technical safety standards to define the timing, methods, and other specifics of O&M activities. In Japan, private sector entities have also led efforts to establish and enhance the monitoring and evaluation of flood management facilities, together with the public sector. For example, the Urban Renaissance Agency (UR) is a public and independent administrative agency in Japan that supplies rental housing in large cities. Through this work, UR aims to provide environmentally and socially attractive spaces for living that are resilient to natural disasters. Flood risk management, therefore, is a key consideration in its housing and urban development initiatives. As such, UR has been monitoring and evaluating the performance of its investments over time. In housing development initiatives such as Akishima Tsutsujigaoka Collective Housing (appendix, case 17) in 1977 and Hachioji Minamino City (appendix, case 14) in 1986, UR combined green and gray solutions to manage flood risk. In both cases, UR monitored the amount of rainfall and the flow rate during implementation, and demonstrated through quantitative data that its integrated approach significantly reduced stormwater runoff. O&M is usually conducted by a public entity (e.g., the city government) that assumes ownership of a completed facility from the developer. However, in these two cases, UR has overseen O&M management for more than 20 years following project completion, conducting monitoring, analysis, and impact assessment of stormwater runoff control facilities. UR’s efforts to proactively collect data and analyze how its investments were able to achieve and sustain flood management capacity have, in turn, lightened the burden of municipal governments (as the facility managers). UR’s monitoring and evaluation results in these two cases are outlined in box 1. Further information is also available in the appendix (cases 14 and 17). 3 Tokyo is a regional government encompassing 23 special wards, 26 cities, 5 towns, and 8 villages. However, reflecting the dense population, urban contiguity, and other realities of the 23 special ward area, a unique administrative system exists between the metropolitan government and the wards, which differs from the typical relationship between prefectures and municipalities. This system balances the need to maintain unified administration and control across the whole of the ward area and the need to have the local ward governments, which are nearer to the residents, handle everyday affairs. Specifically, in the 23 wards, the metropolitan government takes on some of the administrative responsibilities of a “city,” such as water supply and sewerage services, and firefighting, to ensure the provision of uniform, efficient services, while the wards have the autonomy to independently handle affairs close to the lives of the residents such as welfare, education, and housing (TMG n.d.). Learning from Japan’s Experience in Integrated Urban Flood Risk Management Knowledge Note 4: Operating and Maintaining Urban Flood Risk Management Investments 7 Box 1: Monitoring and Evaluating the Impact of Flood Risk Management in Two Urban Housing Development Initiatives Akishima Tsutsujigaoka Collective Housing, Akishima City, Tokyo To meet the growing challenge of urban floods due to the rapid post-1950s urbanization of the Tokyo Metropolitan Area, in 1977 the Urban Renaissance Agency (UR) and the Ministry of Land, Infrastructure, Transport and Tourism (MLIT) embarked on a bold experimental initiative. They set up the first rainwater infiltration system in Japan, at the Akishima Tsutsujigaoka Heights Housing Complex, a 27.8 hectare (ha) residential neighborhood that was home to 2,673 families (Satomi 2013). System components included infiltration containers (49 items), an infiltration trench (494 meters [m] in length), an infiltration U-shaped gutter (143 m in length), and a permeable pavement (3,580 square meters [m2] in area) (Hayashi, Shimada, and Morikami 2002). Monitoring and Evaluating Results As illustrated in figure B1.1, Akishima Tsutsujigaoka Collective Housing was divided into a northern block (1.32 ha), where infiltration measures were installed, and a southern block (1.86 ha), which was managed by normal drainage systems only and where infiltration measures were not installed. In order to compare the stormwater runoff volume of the two blocks, one rain gauge and three flowmeters were set up, and monitoring started in 1981. Changes over the years to the average runoff coefficients of the two blocks (due to changes in land use) were confirmed to be similar (northern block with intervention: 0.65; southern block without intervention: 0.64). Between 1981 and 2000, data on instances of a total rainfall of 30 millimeters (mm) and above, or a peak rainfall of 10 mm/30 minutes or above, were gathered and analyzed. It was found that 109 events met these criteria over the 20-year study period. The analysis also revealed that: • The infiltration facility sustained its flood management function over 20 years. The runoff rate over 20 years remained at around 0.1 for the northern block (that is, with the intervention). Furthermore, its performance under short, concentrated heavy rain, as well as a long, larger total volume of rain was shown to be equally effective, and the performance level did not change over the 20 years of observation. • The urban flood risk management capacity of those areas where the intervention had been implemented was significantly higher than in areas without the intervention. The average runoff rate over the 20 years for the northern block with the intervention was 0.11. This was approximately 20 percent of the average of the southern block without the intervention. The effects of groundwater recharge from the infiltration measures were also monitored and assessed utilizing a simulation model (Similar Hydrologic Element Response [SHER] model), with the following results: • The infiltration facility had a significant groundwater recharge effect. Through the model, one-year rainfall in 2000 was set at 100 percent, and used to estimate the groundwater recharge volume, evapotranspiration volume, and surface water runoff volume for land before development (natural land), area with infiltration facilities, and area without infiltration facilities. The underground water recharge volumes for the northern block with investment and southern block without investment were found to be 50 percent and 24 percent, respectively. This indicated that the groundwater recharge capacity in areas with infiltration investment was twice that of areas without the investment. • The infiltration facility contributed significantly to reducing surface water runoff. Furthermore, surface water runoff volume was also 9 in the block with the investment and 54 in the area without the investment, demonstrating that infiltration measures contributed toward a 80 percent reduction of the runoff. These evaluations were further followed up in 2017, when it was shown that the flood management and groundwater recharge effectiveness of the investments were sustained even after 30 and 35 years of implementation, as illustrated in figure B1.2. Learning from Japan’s Experience in Integrated Urban Flood Risk Management Knowledge Note 4: Operating and Maintaining Urban Flood Risk Management Investments 8 Figure B1.1: Monitoring and Evaluation Area at Akishima Tsutsujigaoka Collective Housing Source: Satomi 2013; Hayashi, Shimada, and Morikami 2002. Note: m2 = square meter. Figure B1.2: Impact of the Stormwater Infiltration System in Akishima Tsutsujigaoka Collective Housing Source: UR N.d.(b). Learning from Japan’s Experience in Integrated Urban Flood Risk Management Even a er 35 years, the rainwater in ltration system is still moistening the earth and controlling the runo of rainwater. Runo rate: the ratio of surface runo to total rainfall. Knowledge Note 4: Operating and Maintaining 0.62 Urban Flood Risk Management Investments 9 Average runo rate of every 5 years 0.59 0.53 0.53 0.54 0.54 Areas without system 0.45 Areas with system Areas without system Hachioji Minamino City, Tokyo Average of 1981-2005 0.13 0.08 0.09 0.10 0.07 0.07 0.08 Similar to Akishima City, Hachioji Minamino City was developed as a new large-scale (394.3 ha) residential neighborhood to accommodate Tokyo’s growing urban population between 1986 and 1997. When the project was proposed, significant Average concerns a er Average were a a er Average raised by residents er Average a er anda the Average er academic Average a er community Average a er regarding Time its potential 5 years 10 years 15 years 20 years 25 years 30 years 35 years the environment impact on(1981-1985) (1986-1990)and associated (1991-1995) risks of urban (1996-2000) response, a (2011-2015) floods. In (2006-2010) (2001-2005) Committee on the Hydrological Cycle Conservation System for Hachioji New Town was formed with participation from the national and local governments, the developer (UR), academia, and citizens. Discussions led to the development of a water circulation and restoration system (Tamura et al. 2007). As part of this system, various pioneering flood mitigation and stormwater storage measures were implemented at that time. The committee played an instrumental role in the system’s design, incorporation, monitoring, and evaluation. System objectives were threefold, touching upon the various aspects of water circulation, including: (i) managing flood risks through reducing stormwater runoff, (ii) enhancing groundwater recharge, and (iii) reducing drought risks through water storage. Stormwater runoff management measures included expanding river channels and sewer drainage, as well as on-site and off-site storage and infiltration facilities. These facilities also aimed to Detention pond A Detention pond A enhance the groundwater recharge. Drought management investments included watershed the construction of permeable with water level embankments, groundwater collection engineering, securing and utilizing spring water monitoring and water from detention point ponds, and appropriate maintenance (i.e., avoiding leakages) of low-lying canals. Monitoring and Evaluating the Multifaceted Impact of the Intervention on Water Circulation In order to monitor and assess the effectiveness of these investments, the flow volume of the Hyoei River, the discharge volume from the detention ponds, rainfall values, etc. were gathered starting in 1996. Data analysis using the SHER model and utilizing information from 1996 to 2012 found that: Hyoei river watershed • Infiltration measures sustained the drought management function. Despite the change in land use due to development, the flow level of the Hyoei River was sustained above the basic level over the observed period. Additionally, although annual variation was observed due to changing rainfall pond B the average water flow patterns, Detention with ground water of the Hyoei River during the dry season remained consistent at around 881 cubic meters (m3) (UR n.d.[a]). level, rainwater The observed drought management capacity from the water circulation and points system (14 percent) restoration monitoring exceeded the estimated design level (10 percent). • Stormwater storage and infiltration measures lowered stormwater runoff. Although rainfall increased significantly after 2005–07, for rainfall over 10 mm/hour that was observed over the 16-year period the runoff rate increased only minimally and remained close to 0.6 percent, which was within the scope of the design 200m rate. Detention pond B • Detention ponds helped manage approximately 2–4.5 mm/hour rainfall with 10,000–18,000 m3 total storage watershed capacity. Figure B1.3: Monitoring and Evaluation Area at Hachioji Minamino City Detention facility Reduced surface runo In ltration Hyoei River In ltration Crushed stone Groundwater Groundwater Impermeable Layer Restoring the impermeable layer Learning from Japan’s Experience in Integrated Urban Flood Risk Management Before A er Knowledge Note 4: Operating and Maintaining Urban Flood Risk Management Investments 10 Source: UR 2008, n.d.(a); Tamura et al. 2007. Note: m = meter. Figure B1.4: A Comparison of Annual Water Balance before and after Stormwater Storage and Infiltration Measures Source: UR 2018. Learning from Japan’s Experience in Integrated Urban Flood Risk Management • Inspection and monitoring results • Establishment of plan • Implementing repair and renewal works Financial management Knowledge Note 4: Operating and Maintaining Urban Flood Risk Management Investments 11 • Mid- to long-term nancial planning 3. Enabling Factors for Effective O&M Human resource management • Personnel management There are a number of enabling factors critical for effective O&M, as listed in table 1. Along with the institutional • Education and training program arrangements described above • Technical as they support relate to the two phases of O&M—that is the design and decision-making system process, and the asset and stock management approaches—IUFRM investments are analyzed against various criteria that enable effective O&M. Specific examples of how these enabling factors play out are described in the following sections: (i) guidelines and manuals; (ii) monitoring and management plans; (iii) engagement of various stakeholders; and (iv) innovative technologies, as visualized in table 1. Although the flood risk type and the unique contexts of each urban flood risk management investment vary significantly, some common tools and approaches have been trialed over the years to enable sustainable and effective O&M. Table 1: Enabling Factors, Tools, and Approaches for Effective O&M Enabling Factors for O&M Description Policy and institutional ameworks Having clear and e ective governance mechanisms and policy incentives for O&M outline the required O&M approach such as regulations, subsidies, assistance, management agreements, etc. are needed and activities, key performance to ensure e ective and regular O&M. Public, private, and community stakeholders all indicators, monitoring and evaluation have a signi cant role to play in promoting e cient and sustainable O&M mechanisms mechanisms, as well as the O&M roles for IUFRM investments. and responsibilities of various For example, gure 6 provides and example from the implementation of the Futako- stakeholders tamagawa Rise and Futakotamagawa Park Project, where O&M responsibilities were shared between the government, private developers, tenants, and community mem- bers, through a combination of policy incentives and collaboration. Tools and Approaches Guidelines and Monitoring and Engagement of Innovative Manuals Management Plans Various Stakeholders Technologies Describe and Require elaborate Human resources include appropriate The engagement of various stakeholders, together with asset owners and managers, knowledge and skills to implement could enhance the e ectiveness and sustainability of O&M as well as ood manage- O&M plans and procedures ment investments. Capacity building, training, and clear guidance on O&M procedures is needed for securing diversi ed human resources for O&M. Guidelines and Monitoring and Engagement of Innovative Manuals Management Plans Various Stakeholders Technologies Ensure and Support and monitor require Investment design takes into consid- Considering the frequency, types, and resources needed for repair, replacement, and eration requirements and ease of reconstruction while selecting the investment design is important. Therefore, explor- O&M ing various ways to lower the O&M cost, extend service life, and as a result reduce life-cycle costs for the investment, is a key design consideration. Guidelines and Monitoring and Engagement of Innovative Manuals Management Plans Various Stakeholders Technologies Inform Enable Learning from Japan’s Experience in Integrated Urban Flood Risk Management Knowledge Note 4: Operating and Maintaining Urban Flood Risk Management Investments 12 Enabling Factors for O&M Description Financial resources are available to Securing nancial resources and reducing the costs of O&M activities will a ect the cost-e ectively carry out necessary sustainability of IUFRM investments. Preventive maintenance and asset management O&M activities throughout the life not only prolong the service life of facilities, but also lower the life-cycle costs. cycle of the investment Box 2 provides an example from Tokyo of the nancial resources mobilized for the O&M of sewerage facilities in the Tokyo Metropolitan Government area, which serves a critical role in managing urban oods in dense urban spaces. In section 4, speci c examples of cost-sharing arrangements between the public sector, private sector, as well as citizens and communities are provided. Tools and Approaches Guidelines and Monitoring and Engagement of Innovative Manuals Management Plans Various Stakeholders Technologies Ensure and Enable and Enable monitor increase Source: Authors’ compilation. Note: IUFRM = integrated urban flood risk management; O&M = operation and maintenance. 3.1 Guidelines and Manuals Flood type Investment Responsible entity In Japan, government agencies, technical institutes, and industry associations, among other entities, have Riverand developed guidelines manuals to not only inform the technical embankments design MLIT but and/or also the municipal actions needed for effective government of ood River O&M IUFRM investments implemented in cities across the country. These guidelines and manuals provide a Underground river over ow management clear policy and institutional framework in setting standards, design MLIT levels, managerrequirements, etc. They and minimum and/or facility facilities (cisterns, channels, etc.) specify the proper frequency, tasks, procedures, quality control, and performance standards for O&M based on the various flood risks and investment Reservoirs, types. detention This parks, andin turn helps facility ponds developers MLIT and operators and/or facility manager consider and integrate O&M requirements within their investment design and management plans, as well as ensure that a certain level of technical standards performance for facilitystormwater Underground is sustained management over time. In addition, the standardization associated with facilities these guides may (cisterns, allow third parties to take pipes, responsibility Municipal government and/or facility manager channels, drainage etc)O&M functions when needed. culverts, for For example, TMG’s technical Stormwater guidelines detention ponds, for stormwater parks, storage and gardens Municipal government, and infiltration facility manager facilities (Tokyo (public or Metropolitan private) and/or community Comprehensive Flood Control Council 2009, n.d.) require one or more periodic inspections in a year, depending on the rainy and typhoon seasons, as well as emergency inspections to conduct necessary repairs whenever a broken Sewerage Municipal government and/or facility manager Surface part ood is identified. At largertreatment and more facility criticalimprovement drainage facilities, technical inspections for preventive purposes are required daily, monthly, and annually according to the importance of the facility. For a facility that has significant Rainwater harvesting systems (collection system andlives, impacts on citizens’ tanks and assets, storage socioeconomic installed activities, inspections in public, commercial, may (public Facility manager be required monthly or private) or community and/or even daily to prevent the facility from breaking community buildings)down and becoming paralyzed. If the facility is not so significant, an inspection once every year is sufficient (MLIT 2016b). Enhancement of in ltration surface (green space, pervious pavers and in ltration trench, etc.) Facility manager (public or private) and/or community The various manuals and guidelines developed in Japan for the O&M of flood management investments prepared by national and local governments, industrial organizations, as well as sectors are illustrated in table 2. Seawalls and gates MLIT and/or municipal government Storm surge ood Ground raising MLIT and/or municipal government Risk assessment, landuse plans, zoning and Municipal government building codes Combined / All Enhancing early warning systems Municipal government, communities Improving evacuation, drills, and awareness raising Municipal government, communities Learning from Japan’s Experience in Integrated Urban Flood Risk Management and awareness raising National government Municipal government Facility manager (public or private) Community Knowledge Note 4: Operating and Maintaining Urban Flood Risk Management Investments 13 Table 2: Manuals and Guidelines for O&M, Monitoring, and Evaluation, by Flood and Investment Type Flood Type Investment Type Key Guidelines and Manuals for Operation, Maintenance, Published by Monitoring, and Evaluation • River Erosion Control: Technical Standards for Maintenance • River Management Facilities such as Levees and Inspection Method for River Channels • Detailed Inspection Method for Embankments around River management facilities, Structures such as Gutters including: • River Management Facilities such as Levees of Medium • River embankments and Small Rivers and Inspection Methods for Riverways River ood • Underground river over ow • River Levee Qualitative Maintenance Technology MLIT4 management facilities (cisterns, Guidelines (plan), 2014 channels, etc.) • River Levee Monitoring Technology Guidelines (plan) • Reservoirs, detention parks, and • Inspection and Evaluation Procedures for River ponds Management Facilities • Levee and Revetment Inspection Results Evaluation Procedure (dra ) • Sluiceway/Gutter Tube Inspection Results Evaluation Procedure: River Edition (dra ) • Guidelines for Selecting PPP / PFI Methods in • MLIT5 Sewerage Projects • Guidelines for Dra Stormwater Management • MLIT6 Comprehensive Plan Sewerage facility: • Guidelines for Implementing Stock Management of • MLIT7 • Underground stormwater Sewerage Projects management facilities • Handbook on Formulating Sewerage Life Extension • MLIT8 (cisterns, channels, drainage Plan Based on Stock Management Method pipes, culverts, etc.) • Comprehensive Private Consignment Introduction • MLIT9 • Stormwater detention ponds, Guidelines for Sewerage Pipeline Facility Management parks, and gardens Work • Sewerage treatment facility • Maintenance Management of Sewage Sludge Treatment • Private improvement in Tokyo Metropolitan Government company10 • Sewerage Pipeline Facility Maintenance Manual • Public Interest Incorporated Association11 Surface water ood • Guidance on Promoting Development of Stormwater • MLIT12 In ltration Facilities (dra ) Stormwater storage and in ltration • Technical Guidelines for Stormwater Storage and • TMG and local facilities, including: municipalities13 In ltration Facilities of Tokyo Metropolitan • Rainwater harvesting systems Government (collection systems and storage • Technical Guidelines for the Installation of Temporary • TMG, Bureau tanks installed in public, Storage Facilities, etc. in Public Facilities of Tokyo of Urban commercial, community Development14 Metropolitan Government buildings) • Technical Guidelines for Stormwater In ltration • Enhancement of in ltration Facilities, Structure, Construction, and surface (green spaces, pervious Maintenance Management (dra ) pavers and in ltration trenches, • Public Interest • River Storage Facilities etc. Technical Guidelines (dra ) etc.) Incorporated • Manual on Stormwater Retention and In ltration Association15 Facilities Installation in Detached Houses Storm surge Coastal Protection Facilities: • Coastal Protection Facility Maintenance and • MLIT and ood Management Manual: Inspection, Evaluation and MAFF (Ministry of • Embankments, revetments, Long-life Planning for Embankment, Revetment, and Agriculture, parapet walls, etc. Parapet Walls, 2014 Forestry and Fisheries)16 Source: Based on MLIT (2013). Note: MLIT = Ministry of Land, Infrastructure, Transport and Tourism; PPP = public-private partnership; PFI = private finance initiative. Knowledge Note 4: Operating and Maintaining Urban Flood Risk Management Investments 14 3.2 Monitoring and Management Plans Monitoring and management plans (or business plans developed by facility owners) take the overall technical and/ or national guidelines and manuals for the various types of flood risk management investments one step further, and define the necessary actions (as well as guidelines regarding their frequency, management, and evaluation), standards, schedules, financial and human resource plans, etc. to carry out the O&M and management actions at each investment project level. These plans are often complemented by a stock/asset database, where the data and information linked to the performance indicators are recorded over time. For example, TMG has been developing a Five-year Sewerage Business Plan since 2007. As in previous plans, the latest 2016–20 plan outlines TMG’s comprehensive strategy to implement a sewerage service that enhances resilience against disasters, improves water and environmental quality, and provides high-quality sewerage services cost-effectively through improved O&M. The plan: (i) establishes a holistic framework for envisioning the entire process up front, taking into account the limited time and financial resources; (ii) clarifies priorities in terms of what actions (inspection, repair, or reconstruction) are to be taken where and when; (iii) combines the work with surface water flood mitigation measures; and (iv) utilizes innovative technologies to expedite the process with minimal impact on the surrounding urban setting. 3.3 Stakeholder Collaboration and Engagement The following sections will introduce examples of the sharing of roles, responsibilities, and financing for the O&M of IUFRM investments between the public sector, the private sector, and citizens and the community. By diversifying the stakeholders involved in the O&M of investments, sources of financial and human resources for O&M can be expanded, lessening the large burden that has been traditionally carried by the public sector, as well as enhancing the skill sets and approaches applied to O&M, and thus the value of urban flood risk management investments. As described in Knowledge Note 3 , multipurpose, multifunction facilities and projects that integrate flood management as part of urban development, environmental conservation, or other public service efforts, are more conducive to the engagement of various stakeholders for O&M than single-purpose flood management measures. For example, in flood detention facilities developed together with a large urban redevelopment initiative, the O&M of the entire facility, including for flood management, may be delegated to the private facility manager, while the public sector may incentivize or lessen the manager’s financial burden by easing regulations, etc. Through effective coordination and advance planning, stakeholders can implement low-cost solutions, such as putting responsibility for O&M into the hands of community members if no advance expertise is required. For example, for a number of years, volunteer activities such as river cleanup by local communities or corporations have been integrated into formal national river maintenance measures (MLIT n.d.[c]). Also, academia can contribute to O&M efforts by studying and developing related technologies as well as providing technical inputs for manuals and advice on O&M implementation, as illustrated in box 1. Sufficient resources (both financial and human) are required to execute periodic, sustainable, and efficient O&M. Cost-effective O&M, in turn, helps ensure that IUFRM investments are sustainable. The following sections describe common mechanisms for sharing costs and responsibilities between the public and private sector, as well as communities. 4 For more details, see http://www.mlit.go.jp/river/kasen/main/maintenance/index.html. 5 For more details, see http://www.mlit.go.jp/common/001170811.pdf. 6 For more details, see http://www.mlit.go.jp/mizukokudo/sewerage/mizukokudo_sewerage_tk_000433.html. 7 For more details, see http://www.mlit.go.jp/river/suibou/pdf/gesui_stockmanagement_guideline2015.pdf. 8 For more details, see http://www.mlit.go.jp/common/001012691.pdf. 9 For more details, see https://www.mlit.go.jp/common/001043219.pdf. 10 For more details, see http://www.tgs-sw.co.jp/business/service/c01/c01/#t01. 11 For more details, see https://www.jascoma.com/doc/book/list/gijutu-h1905.html. 12 For more details, see http://www.mlit.go.jp/common/000113727.pdf. 13 For more details, see http://www.tokyo-sougou-chisui.jp/shishin/shishin.pdf. 14 For more details, see http://www.tokyo-sougou-chisui.jp/shishin/GijutuShishin.pdf. 15 For more details, see https://arsit.or.jp/book14, https://arsit.or.jp/book13 and http://arsit.or.jp/wp/img/book/kodate.pdf. 16 For more details, see http://www.maff.go.jp/j/nousin/bousai/kaigan/ijikanri_manual_iinkai/pdf/manual_main-1.pdf. Learning from Japan’s Experience in Integrated Urban Flood Risk Management Before A er Knowledge Note 4: Operating and Maintaining Urban Flood Risk Management Investments 15 Rainfall 1,493.6 Rainfall 1,493.6 Sharing O&M Costs and Responsibilities with the Public Sector Public sector stakeholders, including the national, provincial, and local governments, can coordinate vertically and horizontally to combine their strengths Over and unique roles across jurisdictions to enhance the effectiveness and ow 738.9 Surface Storage in ltration facility Over ow 374.1 efficiency of O&M. An example of budgeting for O&M is included in box 2. Intermediate ow 50.7 Intermediate ow 59.7 Hyoei River Hyoei River Box 2: Budgeting Groundwater for O&M: Financial Resources Allocated Groundwater to the O&M of Groundwater River Nonpressured and Sewerage Impermeable layer Facilities Impermeable layer in TMG Leakage Impermeable layer Circulation groundwater 97.0 For operation and maintenance (O&M) to be efficient and sustainable, securing financial resources is a first step. In Japan, the required maintenance budget is integrated within annual budget allocations. An increase of 134.4 For example, the Tokyo Metropolitan Government (TMG) in fiscal year (FY) 2016 allocated about ¥115.6 billion ($1.05 billion) for sewerage facilityOther area of pressured maintenance, groundwater which accounted Other for 24 percent of its annual area ofsector sewerage pressured groundwater expenditure of ¥523.2 billion ($4.76 billion). For the river and coastal management facility, TMG budgeted 7.2 percent (¥7 billion; $63 million) of its total annual operational costs to O&M in FY 2016 (Bureau of Sewerage, TMG 2016a; Bureau of Construction, TMG 2016). Figure B2.1: Financial Resources Allocated to the O&M of River and Sewerage Facilities, FY 2016 Sewerage facility maintenance: 24% River and coastal facillty ¥115.6 billion ($1.05 billion) maintenance: 7.2% (¥7 billion; $63 million) Annual sewerage sector expenditure Annual river and coastal management facility expenditure ¥523.2 billion ($4.76 billion) ¥97.3 billion ($884 million) Source: Bureau of Sewerage, TMG 2016a; Bureau of Construction, TMG 2016. For example, at Tetsugakudo Park Collective Housing, the provincial and local (ward) governments worked together to enhance the efficiency of the O&M of stormwater detention facilities within a housing development initiative. To counter the high costs of land and development, TMG extended the use of stormwater detention facilities by cooperating with the local governments of the Shinjuku and Nakano wards and UR, a semipublic housing development corporation, to reduce operation costs and improve land use. The four entities signed two agreements that combined their individual strengths and resources: TMG would fund the installation of a stormwater detention pond; the wards would maintain the parks for local residents; and the developer would address the residential development by constructing convenient amenities with a high profit potential. A stormwater detention facility was constructed below the collective housing building. The pilot17 on the ground floor level of the building acted as an overflow area when the stormwater detention pond exceeded its capacity. Most of the area covered by the O&M agreement is part of a watershed that has multiple land uses. The functions of the water reservoir and the park were funded by a cost-sharing agreement between TMG and the Nakano and Shinjuku wards, and an administrative agreement between the wards and UR. None of the four entities has property rights or exclusive use of the river. As per the administrative agreement, TMG and the two wards will take on the O&M of the stormwater detention pond and the park, respectively. UR will be responsible for the O&M of the piloti and the fence around it under normal circumstances. 17 Piloti are a set of posts raising a building up from the ground. Learning from Japan’s Experience in Integrated Urban Flood Risk Management system and storage tanks installed in public, • River Storage Facility etc. Technical Guidelines (Dra ) commercial, community buildings) • Manual on Stormwater Retention and In ltration • Enhancement of in ltration surface (green Facility Installation in Detached Houses space, pervious pavers and in ltration trench, • Technical Guidelines for Stormwater Storage and etc.) In ltration Facilities of Tokyo Metropolitan Knowledge Note 4: Operating and Maintaining Urban Flood Risk Management Investments Government 16 • Technical Guidelines for the Installation of Temporary Storage Facilities, etc. in Public Facilities of Tokyo However, it is clearly stated that after flooding, the two wards are responsible for removing debris and mud from Metropolitan Government (Tokyo Metropolitan designated administrator the gutters and cleaning the fence. In addition, it is agreed that theComprehensive from the Flood Control Council UR will n.d.) activate the evacuation alarms in case of a disaster event. Sharing O&M Costs and Responsibilities with the Private Sector Storm surge ood Coastal protection facilities: • Coastal Protection Facility Maintenance and Management Manual: Inspection, evaluation and long-life planning for embankment, revetment, and There are many opportunities to engage • Embankment, private theparapet revetment, sector wall, etc. in financing and/or implementing the O&M of urban parapet walls, 2014 flood management investments. In light of the increasing stock of aging infrastructure facilities, Japan is widely promoting the engagement of the private sector through PPPs and PFIs. Various types of arrangements for sharing responsibility for sewerage facilities are illustrated in figure 4. Figure 4: Private Sector Participation in Sewerage Projects in Japan Scope of Work Direct Governance Private Design, Build, Conventional Concession / Individual Outsourcing Subcontracting and Operate PFI Method Top-down execution Municipality Decision making and consensus building Municipality Establishment of Municipality plan Municipality Collection of fee om the public Securing nancial source Municipality Facility (design and Private Sector construction) Facility repair Private Sector and renew Private Sector Inspection and Private Sector maintenance Operation Implementing directly by the Subcontracting services Subcontracting design, Subcontracting design, Subcontracting the municipalities or subcontract- based on tenderer’s building, and O&M as a building, and O&M as a management right. Remarks ing required services to the performance and package ( nancial package ( nancial Private sector to collect private sector. capability, with more than source to be secured source to be secured service fee from the one-year contract. by the public sector). by the private sector). public. Typical contract Approximately Approximately 1 year 3–5 years 15–20 years period 20 years 20 years Number of completed 25 (including - 450 11 1 projects as of ongoing cases) January 2018 Kahoku City etc. TMG etc. Yokohama City Hamamatsu City Implemented - Treatment plant and Project on recycling Project on recycling Treatment plant and cases pumping station’s sewerage pipe’s O&M sewerage sludge sewerage sludge O&M and renovation Source: MLIT n.d.(d). Note: O&M = operation and maintenance; PFI = private financed initiative; TMG = Tokyo Metropolitan Government. Knowledge Note 4: Operating and Maintaining Urban Flood Risk Management Investments 17 Several tools can be used to secure financial resources for the O&M of IUFRM investments. For example, the Shibaura Wastewater Treatment Plant in Tokyo was upgraded in 2015 to increase the underground water retention capacity of untreated stormwater and wastewater to 76,000 cubic meters (m 3), and was funded through a PFI. The project became the first wastewater treatment facility to utilize a new regulatory framework called the Multi- Level City Planning System under the City Planning Act, which enabled “vertical urban planning” that allowed stakeholders to undertake redevelopment projects at multiple levels, regardless of the overlapping public urban facilities beneath or above them. The project in Shibaura comprised two public and private multilayered projects: (i) the underground public sector wastewater and stormwater treatment and detention facility; and (ii) the above- ground private sector commercial redevelopment of a 150 meter (m) high office building and park. TMG, the administrator of the sewerage system, owned a part of the office building in return for leasing the land on which the facility was constructed. Private enterprises paid ¥84.8 billion ($725 million at the time of auction) for a fixed-term contract of 30 years. The revenues generated from leasing the office buildings allowed TMG to keep the sewerage utility fees low, subsidize the cost of repairing other sewerage facilities, and secure stable financial resources for O&M (Hashimoto 2015). (Further information on the Shibaura Wastewater Treatment Facility is included in the appendix, case 11.) The redevelopment of the Yokohama Station Tower and Excite Yokohama 22 District is another example of cost and role sharing between the public and private sector. The initiative combines private urban development with the enhancement of stormwater management capacity in a 5,000 square meter (m2) area. MLIT, Yokohama City, and private developers are collaborating to build the Yokohama Station Tower, a flagship project that is expected to be completed in 2020. As part of this initiative, a stormwater detention cistern with a 170 m3 capacity is under construction below the basement level 3 of a mixed-use 26-story building (Climate Change Adaptation Information Platform 2018). A new national policy, designating the area around Yokohama Station as the first “Flood Mitigation Focus Area” in Japan, was implemented under the revised National Sewerage Law (updated in 2015), which promotes the installation of stormwater storage facilities in large-scale private redevelopment projects through PPPs. The private sector developers conduct O&M of the facilities, but also receive subsidies for the work they do (e.g., for construction of an underground cistern) from the national and local governments (Tanigawa 2017; MLIT 2016a). For this project, private developers paid one-third of the total installation cost, with the remaining two-thirds being subsidized by the national government and Yokohama City (one-third each). In addition to the subsidies, other incentives included a tax reduction for installing a larger storage capacity (300 m3 or more; Ishii 2019). (Further details on the Yokohama Station Tower and Excite Yokohama 22 District are included in the appendix, case 8.) Many new mechanisms and approaches for engaging the private sector in resilient water management are being explored and trialed in Japan, particularly since the Act on Promotion of Private Finance Initiatives (PFI Act) was updated in 2011. For example, Hamamatsu City implemented the first concession project in Japan where the private concessionaire manages and leads the daily O&M and renovation work of, in this case, two pumping stations. The concessionaire has agreed to provide cost-effective sewerage services for a 20-year period, while the city retains responsibility for fee collection and the O&M of sewerage pipes. As a result of this partial concession, cost savings of approximately ¥8.6 billion are expected over the 20 years, including ¥2.5 billion to be paid to Hamamatsu City as concession fees (Suzuki 2019). Learning from Japan’s Experience in Integrated Urban Flood Risk Management Knowledge Note 4: Operating and Maintaining Urban Flood Risk Management Investments 18 Figure 5: Concession Project Scheme for Hamamatsu City’s Sewerage System Project duration: 20 years Service fee Concessionnaire* Public (users) om the Seien District Facilities: ・Seien district sewerage treatment plant Service fee ・2 pumping stations (excluding civil engineering and Providing construction work) operation rights Remarks: ・Concessionnaire’s scope of work for the facilities are as follows: Concession contract Hamamatsu City Management Facilities: ・Sewer pipe networks 100% covered by Concession fee users’ service fee (including civil engineering and construction work of the Seien district sewerage treatment plant and 2 pumping Renovation cost stations) (owned by the city) Maintenance / Daily work Remarks: ・Sewer pipes are out of concession scope because it is more e cient for city to manage them collectively with other 100% covered by Delegation of service districts. users’ service fee fee collection ・Daily work and renovation are outsourced to private contractors by public procurement. State subsidy for Renovation / Renewal Monitoring replacement cost Prefecture 10% covered by users’ service fee 90% covered by Hamamatsu City * Hamamatsu Water Symphony Co., Ltd. established by six companies, including Veolia Japan. Source: Suzuki 2019. New developments that integrate green infrastructure and water-sensitive design are also being managed through PPP schemes. For example, the Futakotamagawa Rise Futakotamagawa Park project (discussed and development Private in the appendix, Public case 2) integrates various green infrastructure features; the rise development is led by the private developer, and the park’s development is led by the city. As described Deregulations of in figure 6, the O&M of the green infrastructure within the height restrictions and oor ratio Integrated design of public Futakotamagawa Rise complex is managed by the company, tenants, and citizens, while the park and private O&M walk of the new public space park is led by the local government. However, using Pro a collaborative approach, the O&M of the entire area involves t facility (Apartment, commercial) various private and citizen’s educational programs and activities (such cleaning, etc.). as parkBridge Sidewalk New public park Road Government: MLIT, TMG, and Setagaya Ward Partially subsidizing Lead construction and O&M Deregulation O&M activities Private developers and landowners: Lead construction and O&M the members of the redevelopment association Coordination Participation in O&M Tenants and community members ー activities ー Learning from Japan’s Experience in Integrated Urban Flood Risk Construction Management Reconstruction Ad hoc maintenance 10% covered by users’ service fee 90% covered by Hamamatsu City Knowledge Note 4: Operating and Maintaining Urban Flood Risk Management Investments 19 * Hamamatsu Water Symphony Co., Ltd. established by six companies, including Veolia Japan. Figure 6: Sharing Responsibility for the Development and O&M of the Futakotamagawa Rise and Futakotamagawa Park Project Private development Public Deregulations of height restrictions and oor ratio Integrated design of public park and private walk space Pro t facility (Apartment, commercial) Sidewalk Bridge New public park Road Partially subsidizing Government: MLIT, TMG, and Setagaya Ward Deregulation O&M activities Lead construction and O&M Private developers and landowners: Lead construction and O&M the members of the redevelopment association Coordination Participation in O&M Tenants and community members ー activities ー Construction Source: Development Bank of Japan 2019. Reconstruction Note: MLIT = Ministry of Land, Infrastructure, Transport and Tourism; O&M = operation and maintenance; Ad hoc maintenanceTMG = Tokyo Metropolitan Government. Similarly, Tokyo Skytree Town was developed by the privately owned Tobu Railway Company. Objectives included constructing a new broadcasting tower, along with promoting the urban renewal of the surrounding neighborhood. Cost Most of Sumida Ward, where the tower is located, is below sea level, making drainage Average and infiltration lifecycle difficult. cost per annum Therefore, the developer built a large stormwater storage tank with a runoff control capacity of 1,835 m3 and a reuse storage capacity of 800 m3. This was the largest in the Tokyo metropolitan area at the time ¥290 construction. of itsmillion Although Sumida Ward has a subsidy scheme for the reuse of stormwater, Tobu Railway Company ($2.5 million) chose not to use 0 the subsidy 10 and instead considered 20 this an opportunity Yearsocial responsibility. Moreover, the to fulfill its corporate company installed stormwater storage facilities with greater capacity than the minimum required and also took charge of their O&M. (Further information on Tokyo Skytree Town is included in the appendix, case 13.) Construction Reconstruction Sharing O&M Costs and Responsibilities with Community Members Planned maintenance O&M responsibilities can also be shared by citizens and communities through bottom-up approaches. Role-sharing ¥240 million mechanisms include O&M agreements, community-based solutions that engage local residents, million)subsidy ($2.1 public programs for O&M, and area management. Examples from Sumida Ward (appendix, case 12) and Higashimurayama Cost City (case 18) in Tokyo showcase bottom-up approaches to sustainable O&M. In Sumida Ward, heavy rains have frequently caused surface water floods and inundation damage since the 1980s. In 1982, the ward kicked off its efforts to store and utilize rainwater by requesting the Japan Sumo Association to use rainwater 0 stadium. Since Sumida 20 at a local sumo 10 25 below Ward is located Yearsea level, stormwater infiltration is not effective in the area. Instead, a stormwater storage facility was adopted as the main stormwater runoff control measure. Given the fact that the ward’s residential areas are widely dispersed, the installation of rainwater storage facilities would involve significant costs. Thus, it was necessary to seek ways to reduce the costs of installation and O&M as well as to promote public awareness of and cooperation with the ward’s policy. To control stormwater runoff in the ward, residents have been voluntarily installing rainwater storage tanks as well as small storage tanks at their homes. Further, Rojisons, or community-based rainwater storage and utilization facilities, were established in 1988 for the purpose of emergency water supply as well as urban flood risk management. As of 2008, there were 21 Rojisons installed in the ward. The rainwater collected from the roofs Floodof residential type buildings is stored in an underground tank, Responsible Investment and residents can pump out the stored rainwater entity with a hand pump for washing streets and watering trees. The ward provides subsidies so that citizens can install River embankments MLIT and/or municipal government Rojisons at a lower cost, and the O&M of rainwater storage tanks is conducted by citizens and local communities. Learning from Japan’s Experience in Integrated Urban Flood Risk Management Knowledge Note 4: Operating and Maintaining Urban Flood Risk Management Investments 20 This reduces the ward’s cost and time for O&M. Rainwater storage tanks installed at residences are visible from the street, which promotes better public awareness of flood risk management. Stormwater storage is promoted by considering how to utilize the stored water. (Further information on Sumida Ward is included in the appendix, case 12.) Hagiyama Shikinomori Park shows how the TMG subsidy program is adopted for supporting green conservation and alleviating the O&M cost of stormwater runoff control facilities. The Privately Developed Park Program, established in 2006 (Bureau of Urban Development, TMG 2006), enables the private sector to develop a park without public finances by deregulating building codes and providing tax waivers for landowners. (Property taxes are waived for 10 years and inheritance taxes are reduced by 40 percent if the land is lent for 20 years or longer.) The program allows business operators to develop high-rise apartment complexes in areas that are otherwise designated for parks and green spaces if they meet certain conditions. Hagiyama Shikinomori Park was the first beneficiary of the program. The total site area was 1.5 ha, 70 percent of which (1 ha) was developed as a park and the rest as apartment complexes that contained 184 apartment units, which were as high as 34–35 m with 11 stories. The site’s land right is owned by an apartment management association, which pays a monthly fee of ¥250,000 (roughly $2,200), or ¥1,400 ($12.30) per apartment unit as the park maintenance fee. In return for opening the park to the public, the apartment complex management company does not have to pay property or urban planning taxes. The private sector supervises the park area and is responsible for its O&M as part of a 35-year contract with the apartment management association; TMG is responsible only for the O&M of the public restrooms (Real Estate Baseball Association 2009). This arrangement reduces the public sector’s O&M burden (further information on Hagiyama Shikinomori Park is included in the appendix, case 18). 3.4 Innovative O&M Technologies In Japan, the private sector is innovating O&M technologies to design and construct flood risk management investments. Adopting advanced technologies and innovative business models not only makes O&M simpler and more efficient but also improves the capacity and the effectiveness of flood risk management throughout the life cycle of an IUFRM investment. It also enables O&M to be managed by a third party, such as a local public entity or private sector organization, which helps reduce the burden of O&M management. Investment designs can incorporate innovative technology to reduce the lifetime costs and/or human resources needed for O&M. For example, Japan has developed a new rehabilitation method for sewer pipes that puts materials made from vinyl chloride around the inside of the pipes. This method allows construction without digging up roads and interrupting traffic on the ground, while reducing costs and construction time, and also allows the continual flow of wastewater. Moreover, this reinforcement makes the sewer pipes more resilient to earthquakes. Thirteen countries in Europe, North America, and Asia, including Germany, Singapore, and the Republic of Korea, have already implemented this solution while renovating their aging sewer pipes. The projects cover a combined total of approximately 111 km of pipes. A box culvert (1,670 mm wide x 1,500 mm high x 30 m long) can reduce O&M costs by approximately 35 percent, compared with other traditional methods such as pipe lining. (Further information on Tokyo Central Wards’ O&M of sewerage facilities is included in the appendix, case 16.) Furthermore, the Government of Japan is leading various initiatives to utilize advanced technology and data to improve the efficiency and effectiveness of aging infrastructure stock, including but not limited to flood management investments. Table 4 summarizes the phases in which the application of advanced technology and data management systems in the field of maintenance and management are being conceptualized and advanced in Japan. An online MLIT platform18 serves as an information hub for O&M updates and good practices, new technologies, etc. for various types of public infrastructure (including river, sewer, and coastal infrastructure) relevant to urban floods. Annual infrastructure maintenance awards are also announced and shared through the platform, which is an important channel for sharing and advancing innovative O&M solutions. Some awards have been for the utilization 18 See http://www.mlit.go.jp/sogoseisaku/maintenance/index.html. Learning from Japan’s Experience in Integrated Urban Flood Risk Management Storm surge Coastal Protection Facilities: • Coastal Protection Facility Maintenance and • MLIT and ood Knowledge Management Note 4: Operating and Maintaining Urban Flood Manual: Inspection, Risk Management Evaluation and Investments MAFF (Ministry 21 of • Embankments, revetments, Long-life Planning for Embankment, Revetment, and Agriculture, parapet walls, etc. Parapet Walls, 2014 Forestry and of Internet of Things (IOT) sensors or drones for the inspection and monitoring of sewerage pipes, led by Fisheries)16 municipal sewage departments (MLIT 2018b). Research and development to further develop and scale such initiatives are ongoing, and several are expected to be tested and applied in the near future. Table 3: Utilization of Advanced Technology and Data in the Field of Maintenance and Management in Japan Type of Advanced Technology for Enhancing Planned/Ongoing Application through National-Level In astructure Operation and Maintenance (O&M) Initiatives Utilization of big data to analyze and model Planning infrastructure conditions across time, develop an Development of infrastructure data platform. O&M plan, and ensure prioritization. Utilization of robots, drones, tablets, and arti cial Inspection and/or prescreening through utilization of Monitoring and intelligence (AI) to enhance the e ciency of robots and drones, sensors, and AI; real-time monitoring inspection monitoring and inspection work; automatic and and recording of data through tablets and mobile real-time monitoring through sensor technologies, devices. etc. Maintenance, Utilization of information and communications The use of drones for surveying and construction, and of repairs, and technology such as 3D data to enhance e ciency Building Information Modeling (BIM), City Information replacement and prioritization of maintenance, repair, and Modeling (CIM) methods to make 3D information on phases replacement work. infrastructure available. Source: MLIT 2018a. Learning from Japan’s Experience in Integrated Urban Flood Risk Management Knowledge Note 4: Operating and Maintaining Urban Flood Risk Management Investments 22 4. Lessons Learned and Key Takeaways Japan’s efforts to sustainably operate and maintain IUFRM investments, as illustrated in the cases reviewed here, provide the following key lessons and takeaways. The function of IUFRM investments can be effective only when the O&M of these facilities is carried out adequately. O&M is thus a crucial component of well-designed IUFRM investments, and enhances (i) ease of updating and adaptation; (ii) cost-effectiveness (by decreasing life-cycle costs); (iii) effectiveness of governance and coordination mechanisms; (iv) use of innovative, appropriate technology and business models; and (v) engagement of citizens and other stakeholders through participation, consensus, and ownership. Executing efficient O&M through preventive maintenance and asset management can reduce life-cycle costs. Effective institutional framework and coordination mechanisms include signed agreements between each stakeholder and related organization. Innovative, appropriate technology and business models not only make O&M easy and efficient, but also enhance and sustain the effects and functions of IUFRM. Bottom-up, low-cost solutions that feature the participation of community members can make O&M more efficient. An integrated approach is key. For large-scale IUFRM investments (such as river embankments) with high O&M costs, a top-down approach led by the national or local government is necessary. But this can be complemented by a bottom-up approach featuring the participation of local residents and community members, who can, for example, help to maintain stormwater storage and infiltration facilities. Engage stakeholders. The goal of IUFRM to reduce flood risks and damage in urban areas is shared among urban public bodies, the private sector, communities, and citizens. Every stakeholder needs to recognize the importance of O&M and help secure the required budgetary and human resources. IUFRM investments with multiple benefits, including commercial and recreational uses, can help to encourage stakeholders’ involvement. Provide incentives for private sector engagement. The private sector may be encouraged to participate where IUFRM measures are implemented in combination with private projects such as large-scale land development and urban redevelopment. Private developers may be expected to proactively undertake the O&M of the IUFRM facilities they install to showcase their capability. Experience from Japanese cities indicates that incentives may include publicly driven policy mechanisms such as easing regulations on floor area quotas (as in Futakotamagawa Rise and Futakotamagawa Park) or requiring a certain level of stormwater management in exchange for subsidies (as in Yokohama Station Tower and Excite Yokohama 22 District). Meanwhile, private developers may see that water- sensitive urban design efforts can enhance their image within society (e.g., Tokyo Skytree Town). Ensuring an array of options for private sector involvement in the O&M of IUFRM projects is crucial. Learning from Japan’s Experience in Integrated Urban Flood Risk Management Knowledge Note 4: Operating and Maintaining Urban Flood Risk Management Investments 23 5. References Bureau of Construction, Tokyo Metropolitan Government (TMG). 2016. “Rivers.” http://www.kensetsu.metro.tokyo.jp/content/000026075.pdf. Bureau of Sewerage, TMG. 2016a. “Tokyo Metropolitan Sewage System Management Plan.” Accessed January 25, 2019. http://www.gesui.metro.tokyo.jp/business/plan/management2016/. ———. 2016b. “Tokyo Sewerage Management Plan 2016.” February. Accessed February 26, 2019. http://www.gesui.metro.tokyo.jp/business/pdf/02kubu_2016.pdf. ———. 2017. “Bureau of Sewerage Business Plan.” http://www.gesui.metro.tokyo.jp/business/pdf/2017report_all.pdf. 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Learning from Japan’s Experience in Integrated Urban Flood Risk Management UFCOP Urban Floods Community of Practice is an umbrella program to share operational and technical experience and solutions for advancing an integrated approach to urban flood risk management, and leveraging expertise and knowledge of different stakeholders and practice groups and across the WBG. The program supports the development of an interactive space for collaboration and exchange on the subject, facilitating users’ access to information and adaptation of knowledge to local conditions, and bringing together different stakeholders to enhance collective knowledge on integrated urban flood risk management. World Bank Tokyo DRM Hub The World Bank Tokyo Disaster Risk Management (DRM) Hub supports developing countries to mainstream DRM in national development planning and investment programs. As part of the Global Facility for Disaster Reduction and Recovery, the DRM Hub provides technical assistance grants and connects Japanese and global DRM expertise and solutions with World Bank teams and government officials. The DRM Hub was established in 2014 through the Japan-World Bank Program for Mainstreaming DRM in Developing Countries—a partnership between Japan’s Ministry of Finance and the World Bank. GFDRR The Global Facility for Disaster Reduction and Recovery (GFDRR) is a global partnership that helps developing countries better understand and reduce their vulnerabilities to natural hazards and adapt to climate change. Working with over 400 local, national, regional, and international partners, GFDRR provides grant financing, technical assistance, training, and knowledge sharing activities to mainstream disaster and climate risk management in policies and strategies. Managed by the World Bank, GFDRR is supported by 36 countries and 10 international organizations. Contact World Bank Disaster Risk Management Hub, Tokyo Phone: +81-3-3597-1320 Email: drmhubtokyo@worldbank.org Website: www.worldbank.org/drmhubtokyo