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Newsletter and Technical Publications

Rainwater Harvesting And Utilisation

An Environmentally Sound Approach for Sustainable
Urban Water Management: An Introductory Guide for Decision-Makers

Profile of Sumida City Government

Sumida City encompasses an area of 13.75 km2, located in the eastern part of Tokyo and surrounded by the Sumida and Arakawa Rivers. The population of Sumida City is 225,935 (as of December 2001). In 1923, the Great Kanto Earthquake hit Sumida City, and 48,400 Sumida City residents died in a huge fire. Again in 1945, the city was completely burnt down by bombing raids during the Second World War.

Sumida City became involved in rainwater utilization projects in 1982. Since then, Sumida City Government has been promoting rainwater utilization in cooperation with its citizens. The Tokyo International Rainwater Utilization Conference (TIRUC), organized by citizens and the Sumida City Government, entitled “Rainwater Utilization Saves the Earth - Form a Friendship with Raindrops in Urban Areas”, was held in Sumida City in August 1994.

After TIRUC, the Sumida City Government produced guidelines and subsidy program for rainwater utilization, in 1995. To date, 300 rainwater tanks have been installed in Sumida City, achieving a total rainwater reservoir capacity of 9000 m3. In 1996, the Sumida City Government organized the Rainwater Utilization Liaison Council for Local Governments. 104 local governments in Japan have joined this council in order to exchange policy ideas and experiences related to rainwater utilization. Sumida City's rainwater utilization projects were selected as an example of "best practice" by the G8 Environmental Futures Forum 2000, and also received an excellence award from ICLEI for "Local Initiatives" in 2000.

Rainwater Museum in Sumida City

The Rainwater Museum is the first facility of its kind in the world. PPRU incorporated five key exhibit designs in the museum. The first is a pumpkin-shaped rainwater tank, which serves as the symbol of the Rainwater Museum. A symbolic message is written on this tank courtesy of the Lanka Rainwater Harvesting Forum (Sri Lanka): "Problem: Water, Solution: Rainwater". Another key exhibit is "Rainwater Crisis", which focuses on water shortages and flooding in urban areas in the 21st Century. The third exhibit provides an introduction to the study of rainwater utilization not only in Japan, but around the World. The fourth exhibit, "Rainwater Utilization Systems", shows collection systems, various types of rainwater tanks, etc. Finally, the fifth main exhibit area is "Thinking Spots". This creative corner provides a space for thinking about the importance of rainwater.

Profile of People for Promoting Rainwater Utilization (PPRU)

PPRU plans to create an International Rain Center to help solve the problems associated with the water crisis in the 21st Century and to promote a rain culture around the world. It will serve as the basis for an international network where information, ideas and experiences related to rainwater utilization can be shared. Included in this international network will be citizens, businesses and public officials.

The promotion of rainwater utilization and a rain culture requires acting locally, and thinking globally. In May 2001, the world's first Rainwater Museum was opened in Sumida City, Tokyo, Japan. City officials of Sumida City commissioned PPRU to create the museum in a vacant primary school in cooperation with the Japan Businesses Association for Rainwater Utilization. The museum presents a wealth of information on rainwater and rain culture from around the world.

In December 2001, PPRU published a Rain Encyclopedia. PPRU has plans to translate this Encyclopedia from Japanese into English and publish the English version. After its publication, PPRU is planning to initiate an International Rain Encyclopedia project in cooperation with other countries.

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