Publication: Return on Investment in Green Urban Development: Amelioration of Flood Risk in the Msimbazi River Catchment, Dar Es Salaam, Tanazania
Loading...
Date
2017-04-01
ISSN
Published
2017-04-01
Editor(s)
Abstract
Rapid urbanisation is taking place at an unprecedented rate throughout the world, with the rate of growth often outpacing urban planning and the capacity of city managers. As a result, existing natural areas within cities,which provide a range of benefits to urban dwellersare becoming smaller and degraded, and problems such as flooding, air pollution and water pollution are becoming worse in many places. African cities often lackthe resources to deal with these problems. However, anumber of studies have suggested that investing in the maintenance or restoration of natural infrastructurein many cases may not only address given problems at comparable or lower cost than conventional engineering projects, but also generate multiple additional benefits that ultimately translate into cost savings and increased human wellbeing. Meanwhile, great strides have been made in the design of sustainable mechanisms to deal with urban environmental issues, stormwater flows and the attendant pollution problems, and management and planning of cities is increasingly taking a holistic approach that includes the use and conservation of semi-natural and natural areas within cities as part of a green urban development strategy. One of the challenges of green urban development will be to findthe right balance between ecological infrastructure(natural systems), “green” (= environmentally friendly)built infrastructure, and conventional (“grey”) built infrastructure. Dar es Salaam, located on Africa’s Indian Ocean Coast,faces a multitude of environmental problems. Prominent among them is the problem of flooding in and around the city centre, which frequently brings the city to a standstill, as well as causing infrastructural damage. Many factors have contributed to this problem, including unplanned informal settlements in the upper catchment and floodplain areas, a lack of drainage and a lack of solid waste management. The impacts of flooding are also exacerbated by high levels of pollution in the rivers, which increases the risks associated with flooding. In consultations for this study, stakeholders in Dar esSalaam identified the Msimbazi River as being amongthe most degraded ecosystems in the city and also the source of the most serious flooding problems. The aim of the study was to explore the potential costs and benefits of undertaking a green urban development approach, including catchment-to-coast restoration measures, to ameliorate flood risk in the Msimbazi Rivercatchment.
Link to Data Set
Citation
“Turpie, Jane; Kroeger, Timm; De Risi, Raffaele; de Paola, Francesco; Letley, Gwyneth; Forsythe, Katherine; Day, Liz. 2017. Return on Investment in Green Urban Development: Amelioration of Flood Risk in the Msimbazi River Catchment, Dar Es Salaam, Tanazania. Promoting Green Urban Development in Africa;. © World Bank. http://hdl.handle.net/10986/26702 License: CC BY 3.0 IGO.”
Associated URLs
Associated content
Other publications in this report series
Journal
Journal Volume
Journal Issue
Collections
Related items
Showing items related by metadata.
Publication Evaluating the Potential Returns to Investing in Green Urban Development in Durban(World Bank, Washington, DC, 2017-04)Urbanisation is taking place at an unprecedented rate throughout the world, often outpacing plans and the capacity of city managers. As a result, natural open space areas in cities are being degraded and diminished, and problems such as flooding, air and water pollution are getting worse. The environmental problems associated with increased hardened surfaces and the loss of natural areas and ecosystem services are particularly acute in developing country cities, where a lack of regulation and resources has led to poor planning, the expansion of informal settlements in high risk, marginal areas, and the inability to adequately manage the quantity and quality of surface water flows.Durban, located within the eThekwini Municipality on the east coast of South Africa, is rich in biodiversity, but faces a number of environmental and developmental challenges. Green urban development is an approach that aims to minimize the impacts of urbanization on the environment, and tackles the core problems of pollution and waste, the consumption of natural resources, the loss of urban open space and the degradation and loss of biodiversity, as well as mitigation of the urban contribution to climate change. The aim of this study was to explore, using a case study and scenario-based approach, the potential costs and benefits of undertaking a green urban development approach to address some of the main environmental issues described above, and to explore the potential tradeoffs between different types of interventions, with an emphasis on assessing the desirable balance between engineered interventions and the conservation of natural open space areas. The study focuses on three elements of green urban development, all of which impact on ecosystems and biodiversity: sewage and solid waste management, active storm water management and the conservation of natural systems and riparian corridors.Publication Greening Africa's Cities(World Bank, Washington, DC, 2017-05-23)Africa is urbanizing late but fast. This brings many benefits but, as this report shows: thus far, urbanization in Africa, unique in a number of respects, is having deleterious and largely unchecked impacts on the natural environment; the degradation of natural assets and ecosystems within African cities carries tangible economic, fiscal and social costs; there are important opportunities to change the current environmental trajectory of African cities so that they move towards a more harmonious relationship between their natural and built environments. For this to happen, focused action is necessary.Publication A Spatial Valuation of the Natural and Semi-Natural Open Space Areas in eThekwini Municipality(World Bank, Washington, DC, 2017)Durban is located within a global biodiversity hotspot, and still contains a wealth of biodiversity. Some of this is protected in nature reserves, but much of it is in private hands or in communal lands on the city’s periphery. City managers are divided over the level of attention that should be given to preserving these remaining natural areas. While it is argued that they make a significant contribution to biodiversity conservation in the province, provide valuable ecosystem services and will contribute to the city’s resilience in the face of climate change, the counter argument is that much of this area should make way for development to alleviate the escalating problem of unemployment. The study of ecosystem services and their value to society has made significant advances since an estimate was made of Durban’s ecosystem services in the 1990s using early values from the international literature. The aim of this study was to provide estimates of the value of ecosystem services provided by natural open space areas within the eThekwini Municipal Area (EMA), and to map the geographic variation in these values as far as possible so as to be able to compare both areas and types of value, using available and locally-relevant data. This study was carried out as a desktop study based on available data. Modelling assumptions were based on data from within the study area, drawing on the regional, national or international literature only where necessary. The study focused on the direct values associated with the provision of natural resources, indirect use values associated with regulating services generated by ecosystem functioning, and the amenity values generated by ecosystem attributes.Publication Climate Variability and Change : A Basin Scale Indicator Approach to Understanding the Risk to Water Resources Development and Management(World Bank, Washington, DC, 2011-09)The impact of climate change is likely to have considerable implications for water resource planning, as well as adding to the risks to water infrastructure systems and effecting return on investments. Attention is increasingly being paid to adaptation strategies at the regional and basin level; however, the current paucity of information regarding the potential risk to hydrological systems at this scale presents a substantial challenge for effective water resources planning and investment. This study is intended to help bridge the gap between high-level climate change predictions and the needs of decision-makers, including World Bank Task Team Leaders, government agencies, investors, and national economic development planners, whose programs and investments will be affected by basin- and regional-level impacts of climate change on water resources and related infrastructures. This study evaluates the effects of climate change on six hydrological indicators across 8,413 basins in World Bank client countries. These indicators, mean annual runoff (MAR), basin yield, annual high flow, annual low flow, groundwater (base-flow), and reference crop water deficit, were chosen based on their relevance to the wide range of water resource development projects planned for the future. To generate a robust, high-resolution understanding of possible risk, this analysis examines relative changes in all variables from the historical baseline (1961 to 1999) to the 2030s and 2050s for the full range of 56 General Circulation Model (GCM) Special Report on Emissions Scenario (SRES) combinations evaluated in the Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report (AR4).Publication A Preliminary Investigation of the Potential Costs and Benefits of Rehabilitation of the Nakivubo Wetland, Kampala(World Bank, Washington, DC, 2016-09)Rapid urbanisation threatens existing natural areas withincities and the ecosystem services that they provide. This case study forms part of a broader study that investigates the benefits of investing in Green Urban Developmentin African cities. The Kampala case study focuses on the Nakivubo wetland, one of several large wetland systems that occur within and around the city. This wetland has become severely degraded by polluted water from thecity that passes through the wetland before entering Inner Murchison Bay. However, as the city has continued to grow, pollution flows into the wetland have increased significantly, the size and assimilative capacity of the wetland has decreased, and the costs of water treatment have increased. These concerns, as well as the increasing shortage of public open space areas in the city that are available for recreation, haveled to the city’s consideration of the rehabilitation of the Nakivubo wetland, both to restore its functioning and to create the opportunity for a recreational area with associated possibilities for economic development. This study provides a preliminary evaluation of the state of the Nakivubo wetland, the potential costs and benefitsof its rehabilitation and the implications for the city’sexpansion plans. The primary objectives were defined as(1) effecting a measurable improvement of waterquality passing out of the Nakivubo wetland into InnerMurchison Bay, (2) ensuring sustainable management ofthe Nakivubo wetland, (3) reducing water quality impactson human health and (4) opening up opportunitiesfor safe recreational use of the lower wetland. One of the main challenges in achieving the above would be institutional. Greater Kampala extends well beyond the boundaries of the Kampala Capital City Authority (KCCA), which originally encompassed the entire city, and unless the KCCA area is adjusted accordingly (as has been done in other countries), the problems that will arise in a growing city will be in areas under multiple other jurisdictions.
Users also downloaded
Showing related downloaded files
Publication Africa's Future, Africa's Challenge : Early Childhood Care and Development in Sub-Saharan Africa(Washington, DC : World Bank, 2008)This book seeks to achieve a balance, describing challenges that are being faced as well as developments that are underway. It seeks a balance in terms of the voices heard, including not just voices of the North commenting on the South, but voices from the South, and in concert with the North. It seeks to provide the voices of specialists and generalists, of those from international and local organizations, from academia and the field. It seeks a diversity of views and values. Such diversity and complexity are the reality of Sub-Saharan Africa (SSA) today. The major focus of this book is on SSA from the Sahel south. Approximately 130 million children between birth and age 6 live in SSA. Every year 27 million children are born, and every year 4.7 million children under age 5 die. Rates of birth and of child deaths are consistently higher in SSA than in any other part of the world; the under-5 mortality rate of 163 per 1,000 is twice that of the rest of the developing world and 30 times that of industrialized countries (UNICEF 2006). Of the children who are born, 65 percent will experience poverty, 14 million will be orphans affected by HIV/AIDS directly and within their families and one-third will experience exclusion because of their gender or ethnicity.Publication Ten Steps to a Results-Based Monitoring and Evaluation System : A Handbook for Development Practitioners(Washington, DC: World Bank, 2004)An effective state is essential to achieving socio-economic and sustainable development. With the advent of globalization, there are growing pressures on governments and organizations around the world to be more responsive to the demands of internal and external stakeholders for good governance, accountability and transparency, greater development effectiveness, and delivery of tangible results. Governments, parliaments, citizens, the private sector, Non-governmental Organizations (NGOs), civil society, international organizations, and donors are among the stakeholders interested in better performance. As demands for greater accountability and real results have increased, there is an attendant need for enhanced results-based monitoring and evaluation of policies, programs, and projects. This handbook provides a comprehensive ten-step model that will help guide development practitioners through the process of designing and building a results-based monitoring and evaluation system. These steps begin with a 'readiness assessment' and take the practitioner through the design, management, and importantly, the sustainability of such systems. The handbook describes each step in detail, the tasks needed to complete each one, and the tools available to help along the way.Publication Tanzania(World Bank, Washington, DC, 2015-06)This study aims to achieve a better understanding of the agricultural risk and risk management situation in Tanzania with a view to identifying key solutions to reduce current gross domestic product (GDP) growth volatility. For the purpose of this assessment, risk is defined as the probability that an uncertain event will occur that can potentially produce losses to participants along the supply chain. Persistence of unmanaged risks in agriculture is a cause of great economic losses for farmers and other actors along the supply chains (for example, traders, processors, and exporters), affecting export earnings and food security. The agricultural sector risk assessment is a straightforward methodology based on a three-phase sequential process. Phase analyzes the chronological occurrence of inter-seasonal agricultural risks with a view to identify and prioritize the risks that are the drivers of agricultural GDP volatility. This report contains the findings and recommendations of the first phase and includes the identification, analysis, and prioritization of major risks facing the agricultural sector in Tanzania, as well as recommendations regarding key solutions. Chapter one gives introduction and context. Chapter two contains an overview of the agricultural sector and its performance, as well as a discussion of key agro-climatic, weather, and policy restrictions and opportunities. Chapter three includes an assessment of major risks (that is, production, market, and enabling environment risks) facing key export and food crops. Chapter four presents an estimate of historical losses due to realized production risks and a correlation of such losses with production volatility. Chapter five provides insights into the exposure to risks by different stakeholders and their actual capacities, vulnerabilities, and potential to manage agricultural risks. Chapter six presents a risk prioritization by different supply chains and discusses the possible solutions, as well as specific recommendations for the agricultural sector development program (ASDP).Publication World Development Report 1984(New York: Oxford University Press, 1984)Long-term needs and sustained effort are underlying themes in this year's report. As with most of its predecessors, it is divided into two parts. The first looks at economic performance, past and prospective. The second part is this year devoted to population - the causes and consequences of rapid population growth, its link to development, why it has slowed down in some developing countries. The two parts mirror each other: economic policy and performance in the next decade will matter for population growth in the developing countries for several decades beyond. Population policy and change in the rest of this century will set the terms for the whole of development strategy in the next. In both cases, policy changes will not yield immediate benefits, but delay will reduce the room for maneuver that policy makers will have in years to come.Publication World Development Report 2017(Washington, DC: World Bank, 2017-01-30)Why are carefully designed, sensible policies too often not adopted or implemented? When they are, why do they often fail to generate development outcomes such as security, growth, and equity? And why do some bad policies endure? This book addresses these fundamental questions, which are at the heart of development. Policy making and policy implementation do not occur in a vacuum. Rather, they take place in complex political and social settings, in which individuals and groups with unequal power interact within changing rules as they pursue conflicting interests. The process of these interactions is what this Report calls governance, and the space in which these interactions take place, the policy arena. The capacity of actors to commit and their willingness to cooperate and coordinate to achieve socially desirable goals are what matter for effectiveness. However, who bargains, who is excluded, and what barriers block entry to the policy arena determine the selection and implementation of policies and, consequently, their impact on development outcomes. Exclusion, capture, and clientelism are manifestations of power asymmetries that lead to failures to achieve security, growth, and equity. The distribution of power in society is partly determined by history. Yet, there is room for positive change. This Report reveals that governance can mitigate, even overcome, power asymmetries to bring about more effective policy interventions that achieve sustainable improvements in security, growth, and equity. This happens by shifting the incentives of those with power, reshaping their preferences in favor of good outcomes, and taking into account the interests of previously excluded participants. These changes can come about through bargains among elites and greater citizen engagement, as well as by international actors supporting rules that strengthen coalitions for reform.