评估城市防洪项目的次要效益：以波兰弗罗茨瓦夫为例

11178 Assessing Secondary Benefits of UrbanFlood Protection Projects The Case of Wroclaw, Poland Winston YuRan GoldblattTess DoeffingerRoss EisenbergSteven Rubinyi Water Global Department &Urban, Disaster Risk Management, Resilience and Land Global DepartmentJuly 2025 Policy Research Working Paper11178 Abstract With global climate change impacting cities around theworld, local and national governments need to plan for andinvest in solutions that mitigate the climate and disasterrisks their populations and economies face. Urban floodingposes an acute threat to sustainable and equitable urbangrowth and wellbeing. While the primary benefit of invest-ments in urban flood protection is the avoidance of futuredamages and losses, such investments can also provide sec-ondary benefits that can help unlock localized economicpotential and contribute toward green growth. Althoughsecondary benefits of investments in urban flood protectioncan be difficult to assess and quantify, the growing availabil-ity of locally sourced and remotely sensed data opens new possibilities. This study presents a spatially focused meth-odology that employs proxies to provide further evidenceof secondary benefits linked to large-scale investments inurban flood protection in Wroclaw, Poland. Within newlyprotected areas, the study finds increases in land and res-idential real estate values, and an increase in economicdevelopment in parallel to on an increase in nighttime lightintensity and built-up area. The study also finds that therelative rate of change for land and residential real estatevalues, nighttime light intensity, and built-up area withinareas newly protected from flooding outstripped that ofother areas of the city. This paper is a product of the Water Global Department and the Urban, Disaster Risk Management, Resilience andLand Global Department. It is part of a larger effort by the World Bank to provide open access to its research and make acontribution to development policy discussions around the world. Policy Research Working Papers are also posted on the Webat http://www.worldbank.org/prwp. The authors may be contacted at wyu@worldbank.org, reisenberg1@worldbank.org,and srubinyi@worldbank.org. The Policy Research Working Paper Series disseminates the findings of work in progress to encourage the exchange of ideas about developmentissues. An objective of the series is to get the findings out quickly, even if the presentations are less than fully polished. The papers carry thenames of the authors and should be cited accordingly. The findings, interpretations, and conclusions expressed in this paper are entirely thoseof the authors. They do not necessarily represent the views of the International Bank for Reconstruction and Development/World Bank andits affiliated organizations, or those of the Executive Directors of the World Bank or the governments they represent. Assessing Secondary Benefits of Urban Flood Protection Projects: The Case ofWroclaw, Poland Winston Yu, Ran Goldblatt, Tess Doeffinger, Ross Eisenberg, Steven Rubinyi Keywords:secondary benefits, cost benefit analysis, urban flood protection JEL Classification Codes: C21(Spatial Models); Q54(Natural Disasters and Their Management); P25(Urban, Rural, and Regional Economics);O44(Environment and Growth);R11(Regional EconomicActivity: Growth, Development, Environmental Issues, and Changes) 1.Introduction 1.1.The global challenge of urban flooding In this century’s first 20 years, floods and storms have caused nearly 166,000 deaths andaccounted for 69% of global natural disaster financial damages (Amarasinghe et al., 2020). Floodevents with 100 deaths and more occur globally on average 10 times a year(Jonkman et al., 2024).Between 1980 and 2011, hydrological phenomena caused more than €140 billion ($165 billion) indamage in Europe alone (Erdlenbruch & Grelot, 2017). Beyond the direct destruction they cause,floods have other significant short-, medium-, and long-term impacts on society, such as changesin peoples’ means of subsistence, migratory processes, psychosocial health, relationships withinand between communities, and regional development (WHO, 2017). Over the next century,climatechange will amplify both the frequency and severity of flooding and otherhydrometeorological hazards (WHO, 2008; Peterson et al., 2013; Steffen et al., 2014). In parallel to the effects of climate change, the world has seen a dramatic increase in the numberof people living in cities—particularly in rapidly developing countries. Between 1950 and 2014,the share of the global population living in urban areas increased from 30% to 54% (UN, 2015).By 2050, an additional 2.5 billion people are expected to live in urban areas (UN, 2015). Thisintensifying urbanization concentrates the exposure of populations and assets to floodinghazards. Other factors, including socioeconomic (i.e. location within cities, poor access toinformation, little resources and ability to prepare, respond, a