Revision of the Tokyo Metropolitan Government Torrential Rain Countermeasures Basic Policy

The Tokyo Metropolitan Government established the “Tokyo Metropolitan Government Torrential Rain Countermeasures Basic Policy” to guide comprehensive flood control measures, including the maintenance of river and sewerage systems, as well as the installation of storage and infiltration facilities. In recent years, however, the increasing severity and frequency of torrential rain events due to climate change have highlighted the need for enhanced preparedness.
To address these challenges, the Tokyo Metropolitan Government convened the Torrential Rainfall Countermeasures Review Committee, comprised of academic experts and other stakeholders. The committee has been evaluating future countermeasures for Tokyo, focusing on adapting to the projected impacts of climate change.
Based on the considerations outlined above, we are pleased to announce the revision of the “Tokyo Metropolitan Government Torrential Rain Countermeasures Basic Policy.”

Key updates in the revised Policy

(1) Enhanced Rainfall Target. To address a 1.1-fold increase in rainfall due to climate change, the target rainfall has been raised by 10 mm across Tokyo.
(2) Flood Damage Prevention. Flood risks will be mitigated through a combination of measures, including river and sewerage system maintenance, and watershed-based solutions.
(3) Preparedness for Extreme Rainfall. For rainfall events exceeding the target threshold, a comprehensive approach will be implemented, encompassing five strategies such as resilient building designs, community development, and enhanced evacuation measures.
(4) Priority Areas and Phased Implementation. Priority areas for countermeasures have been designated to strengthen key initiatives and achieve early operational effectiveness. The system will be gradually expanded across all of Tokyo.

How to Browse

Details of the published materials and the results of the public comment gathering session can be viewed on the website of the Bureau of Urban Development.
https://www.toshiseibi.metro.tokyo.lg.jp/kiban/gouu_houshin/index.html (available only in Japanese)

 

Creation of a Video of “What You Can Do to Prevent Flood Damage in Torrential Rain”

We have created a video to help you understand practical steps you can take in your daily life to reduce the risk of flood damage during heavy rain.
We will continue to improve the content so that more people can learn the essentials of heavy rain countermeasures and take proactive steps to protect themselves.
https://www.toshiseibi.metro.tokyo.lg.jp/kiban/gouu_houshin/gouu_taisaku.html (available only in Japanese)

This projectaims to promote the “Future Tokyo: Tokyo's Long-Term Strategy.”
Strategy 8: Strategy for Developing a Safe and Secure City 
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