Evolution of Risk-Informed Land Use Regulations and Controls in Japan

Land use regulations and controls in Japan have evolved in response to the needs and changes in the social background, as well as experiences of substantial disaster losses and damage. With the unprecedented scenario of an aging and depopulating society, as well as impacts of climate change: Target hazards have been expanded in terms of hazard type, disaster cause, and assumed scale. Target area designation has been expanded to include presumed affected areas, and regulated development and construction have been expanded to reduce exposure to disaster risk. More recently, necessary soft measures such as securing warning and evacuation systems have been additionally integrated. Despite the advancement of risk-informed land use regulations and controls in Japan, their practical implementation has been challenged due to social, institutional, and legal constraints. In practice, area designation has not been fully implemented due to insufficient capacities in terms of technical and financial resources at the local level. Although land use restrictions have promoted relocation and retrofit of buildings, they do not have an immediate effect to change exposure; therefore, a spatial master plan of disaster risk reduction with a timeline is imperative. While the government improves risk information and communication, people and society, as recipients of information, should strengthen their capacity to understand risk at all times and take necessary actions in times of disaster, through a multi-hazard approach in a multi-stakeholder framework. In the long run, systems are required that could transform the entire national land structure into a more resilient, “autonomous, decentralized, and coordinated” structure from a broader perspective.