Risk-based land use and spatial planning Miho OHARA International Centre for Water Hazards and Risk Management (ICHARM) Public Works Research Institute PWRI), Japan Under the auspices of UNESCO
Introduction of ICHARM International Centre for Water Hazards and Risk Management (ICHARM) was officially established as a UNESCO category II center and a part of the Public Works Research Institute of Japan on March 6, 2006. Hazard Assessment Flood modeling and simulation Innovative Research Risk Assessment Effective Capacity Building Efficient Information Networking Workshop Training Master and PhD students
Risk-based land use and spatial planning Final Goal: Disaster Risk Reduction Combination with Other Countermeasures Understanding from Citizens Land Use and Spatial Planning Contribution from Private Sector Building Social Consensus for Identification of Target Hazard Risk Assessment & Risk Identification Data & Statistics
1. Example of Risk-based Approach after the 2011 Great East Japan Earthquake in Japan -As a consequence of gigantic tsunamis which hit the Pacific coast of Japan, 19,535 people died and 2,585 are still missing as of March 2017. Two Target Levels of Tsunami I tegrated easures o i i g structural and non-structural measures. Level 2 Tsunami: Largest scale tsunami The height of tsunami at 2011 event Levee improved after 2011 tsunami Level 1 Tsunami: Frequent tsunami Levee before 2011 tsunami Land subsidence Damaged levee due to 2011 tsunami Adopted by Ministry of Land, Infrastructure, Transport and Tourism (MLIT) and translated by ICHARM
Role of National and Local Gover e ts for Build Ba k Better National Level: Legal framework of Disaster Risk Area by Building Standard Act. Local government Level: Designation of Disaster Risk Area by ordinances Relocation Projects for residences to move to safer land. Levee for protecting Level 1 tsunami Ishinomaki City Disaster Risk Area Houses, Evacuation facility Road Elevated Road Levee Levee Factory, Park (No house) Outside Disaster Risk Area Schools, Hospitals, Evacuation space Evacuation Tower
Current Status of Relocation to Safer Land -Relocations are still underway. Land Development of Relocation -By March, 2017, almost 90% of the land development for relocation has been done. -By March, 2018, it is scheduled to be completed. Disaster Risk Area Adopted by Reconstruction Agency
Act for Tsunami-Resilient Cities (2011) -A new act for tsunami-resilient cities was enacted in order to reduce tsunami disaster risk in all coastal areas in Japan. Adopted by Ministry of Land, Infrastructure, Transport and Tourism (MLIT) and translated by ICHARM
2. Example of Practical Approach by Local Government Considering Flood Inundation Probability -Shiga Prefecture adopted a unique policy for integrated flood management considering flood inundation probability in land use planning. Laser-scanned Precise Elevation Map High-resolution Inundation Simulation Precise Flood Inundation Mapping 10 Year Return Period 100 Year Return Period 200 Year Return Period Adopted by Shiga Prefectural Government and translated by ICHARM
Risk Matrix for Land Use Planning -Shiga Prefe ture is o du ti g la d use pla i g usi g Risk Matrix. La d use is determined according to the inundation probability and inundation level. If an inundation of over 50 centimeters deep is expected to occur more than once in 10 years, the area will be taken off the list of areas for future urbanization. 1/ 10 (0.100) 1/ 30 (0.033) 1/ 50 (0.020) 1/100 (0.010) 1/200 (0.005) ------ Inundation Probability 1/ 2 (0.500) High Risk If an inundation of over 3 meters deep is expected to occur more than once in 200 years, the area is designated as Flood Risk Zo e, with building regulation. Low Risk Inundation Level h<0.1m 0.1<h 0.5<h h>=3.0 <0.5m <3.0m m https://www.e3s-conferences.org/articles/e3sconf/pdf/2016/02/e3sconf_flood2016_13008.pdf
Conclusions National Level Legal framework for ensuring sustainability Science and technology for risk assessment to identify and monitor risk Building consensus for identification of target hazard level Realizatio of Build Ba k Better Local Government Level More risk sensitive land use and spatial planning Combination with other countermeasures such as evacuation, multiple uses of infrastructures, etc. International Cooperation Information sharing of good practices Training of engineers and practitioners http://www.icharm.pwri.go.jp/