URBAN FLOOD RISK MANAGEMENT IN THE PACIFIC: TRACKING PROGRESS AND SETTING PRIORITIES Urban Floods Community of Practice Urban KNOWLEDGE NOTES KNOWLEDGE DECEMBER 2017 2 URBAN FLOOD RISK MANAGEMENT IN THE PACIFIC CONTENTS Acknowledgments ....................................................... 3 Conduct community studies .................................... 30 Abbreviations ............................................................... 3 Develop local damage functions for risk assessments ................................ 30 Summary ..................................................................... 4 Identify risk tolerability ............................................ 31 Introduction .................................................................. 6 Employ multicriteria analysis .................................... 31 Flood Impacts in PICs .................................................. 7 Prepare FRM Plan .................................................. 31 Loss of life ............................................................. 7 4. Reframe the problem .............................................. 32 Impacts on health and education ......................... 8 5. Broaden the solutions ............................................. 32 Impacts on infrastructure ...................................... 8 6. Preserve and enhance the capacity of river Financial and economic costs ............................... 8 channels and floodplains to convey flows .............. 32 Drivers of Flood Disaster Risk in PICs ........................ 9 7. Reduce exposure and vulnerability .......................... 32 Climate variability and change .............................. 9 Consider voluntary relocation................................... 33 Environmental change .......................................... 11 Practice risk-informed land use planning .................... 33 Floodplain development and urbanization ............ 11 Encourage resilient buildings ................................... 34 Flood Risk Management Process ............................... 13 Encourage resilient infrastructure ............................. 34 Tracking Flood Risk Management 8. Enhance response ................................................... 34 Practice in the Pacific Islands ...................................... 14 Develop EWS ........................................................ 34 Benchmark 1: Hydrological data Improve emergency management collection/storage/reliability ....................................17 planning and capability ............................................ 34 Benchmark 2: Hazard assessment (mapping) ......18 Foster community preparedness .............................. 35 Benchmark 3: Exposure and Conclusion and Key Messages for Policy Makers ...... 35 vulnerability assessment (mapping) ......................19 References ................................................................... 37 Benchmark 4: Risk assessment ............................20 Annex 1: Tracking Flood Risk Benchmark 5: Flood risk management measures 21 Management Practice ................................................. 41 Benchmark 6: Flood modification measures ........ 22 Benchmark 1: Hydrological data Benchmark 7: Risk-informed land use collection/storage/reliability ................................... 41 planning and development controls ...................... 23 Benchmark 2: Hazard assessment (mapping) ..... 42 Benchmark 8: Flash flood warning systems ......... 24 Benchmark 3: Exposure and vulnerability Benchmark 9: Emergency assessment (mapping) ......................................... 43 management planning and capability .................... 25 Benchmark 4: Risk assessment ........................... 43 Benchmark 10: Community preparedness ........... 26 Benchmark 5: Flood risk Benchmark 11: Flood risk management measures ....................................... 44 management governance ...................................... 27 Benchmark 6: Flood modification measures ....... 45 Benchmark 12: Flood risk Benchmark 7: Risk-informed land use management process rollout ................................. 28 planning and development controls ..................... 46 Priorities for Improving Flood Risk Benchmark 8: Flash flood warning systems ........ 47 Management Practice ................................................. 29 Benchmark 9: Emergency management 1. Improve governance ......................................... 29 planning and capability .......................................... 48 2. Involve communities and other stakeholders .. 30 Benchmark 10: Community preparedness .......... 49 3. Apply a flood risk management process .............. 30 Benchmark 11: FRM governance ......................... 51 Improve and sustain Benchmark 12: FRM process roll out ................... hydrological monitoring ..............................................30 53 Conduct flood studies ................................................30 URBAN FLOOD RISK MANAGEMENT IN THE PACIFIC 3 ACKNOWLEDGMENTS Authors: Stephen Yeo, Simone Esler, Felix Taaffe, Denis Jordy, and Michael Bonte-Grapentin We are grateful to many people who gave their time to help us understand flood risk management practices and needs in each country. These include A. Tuifagalele, M. Reddy, N. Khan, and V. Vereivalu (Fiji); F. Nelson, F. Reupena, F. Yandall-Alama, I. Punivalu, M. Iakopo, S. Sesega, and S. Tiatia (Samoa); A. McNeil (Solomon Islands); and P. Korisa and J. Timothy (Vanuatu). We also extend our thanks to Litea Biukoto (Pacific Community), Steve Clark (Water Technology), Doug Ramsay (National Institute of Water and Atmospheric Research), and Karen Lummis (Australian Department of Foreign Affairs and Trade). Finally, we thank the following World Bank Group personnel for providing feedback and peer review during the preparation of this report: Abhas Jha, Zuzana Stanton-Geddes, Xiaokai Li, Toshihiro Sonoda, Dzung Huy Nguyen, Joop Stoutjesdijk, Loren Atkins, and Brenden Jongman. Designed by: Johanna Mora. Cover image: Solomon Star ABBREVIATIONS AAD Average annual damage MNRE Ministry of Natural Resources ADB Asian Development Bank and Environment (Samoa) AEP Annual Exceedance Probability NDMO National Disaster Management Office CCA climate change adaptation NEOC National Emergency Operations CRISP Community Resilience to Climate Centre and Disaster Risk in Solomon Islands Project (World Bank Group) NGO nongovernmental organization DRR disaster risk reduction NIWA National Institute of Water and Atmospheric Research (New EWS early warning system(s) Zealand) FRM flood risk management Pacific- Pacific Hydrological Cycle FRMP Flood Risk Management Plan HYCOS Observing System GDP gross domestic product PCRAFI Pacific Catastrophe Risk GPVURCAP Greater Port Vila Urban Resilience Assessment and Financing Initiative and Climate Adaptation Plan PDNA Post-Disaster Needs Assessment HEDSUP Honiara Economic Development PIC Pacific Island Country Support Programme PREP Pacific Resilience Program HURCAP Honiara Urban Resilience and (World Bank Group) Climate Action Plan PUMA Planning and Urban Management IWMP Integrated Watershed Agency (Samoa) Management Plan SPC Pacific Community IWRM Integrated Water Resources SPREP Secretariat of the Pacific Regional Management Environment Programme JICA Japan International TC Tropical Cyclone Cooperation Agency URMS Urban Risk Management Strategy (Vanuatu) This knowledge note was prepared under the Building Climate and Disaster Resilience in the Pacific program, with financial support from the European Union (EU) in the framework of the ACP-EU Natural Disaster Risk Reduction Program, managed by the Global Facility for Disaster Reduction and Recovery (GFDRR) and the Urban Floods Community of Practice (UFCOP). UFCOP is a global knowledge initiative led by the World Bank with support from GFDRR and others. 4 URBAN FLOOD RISK MANAGEMENT IN THE PACIFIC SUMMARY Floods have caused significant damage to urban communities in Pacific Island Countries (PICs). The principal driver of this increasing problem is the growth of exposure to flooding associated with population growth and urbanization. Flood hazards are also expected to increase with climate change. This Knowledge Note describes a benchmarking method developed to track the progress of PICs toward best-practice flood risk management (FRM). FRM is a process for assessing flood risk, evaluating options to manage the risk, and implementing a strategic plan to reduce risk. The method was applied to assess current urban FRM practices in Fiji, Samoa, the Solomon Islands, and Vanuatu, focusing on riverine flood hazards1. The results show the following: • The quality of hydrological data available for hydrodynamic modeling is generally poor, reflecting institutional and resourcing issues. Nonetheless, in recent years significant advances have been made in flood modeling and mapping for some of the most urbanized floodplains in the region. • Reasonably good exposure data sets are available for some of the most flood-prone cities and towns in the region, but few studies have assessed the risk to property and life for the full range of floods that may be experienced. • There has been a tendency for PICs to implement structural works rather than softer solutions, sometimes without comprehensive assessments and engagement. • Risk-informed land use planning has faced many challenges, including the extent of customary land ownership and the growth of informal settlements, and has been slow to take hold. • There has been some