This report outlines the ways Japan has built the resilience of its water supply and sanitation (WSS) services through an adaptive approach based on lessons learned from past natural disasters. It describes legal and institutional frameworks for resilient water supply and sanitation services in the country and outlines best practices and lessons learned from WSS utilities in the cities of Fukuoka, Hiroshima, Kobe, Kumamoto, Sendai and Tokyo. Japan's experience offers key insights for low- and middle income countries seeking to reduce their vulnerabilities in essential service provision.
Natural disasters have increasingly damaged WSS facilities and infrastructure, leaving entire communities without safe and reliable drinking water and the appropriate disposal of wastewater. These emergency events could arise from inundation of facilities, loss of electricity, and exposure and disruption of infrastructures. Less severe impacts can arise from increased siltation of reservoirs and slow-onset events such as droughts, thus having longer-term effects on the resilience and reliability of services. These WSS service failures or interruptions could set off a cascading effect across interconnected infrastructure systems including public health and fire services, which in turn could pose both direct and indirect economic impacts.