SATO Project

Sowing seeds of rainwater harvesting globally

Makoto Murase
CEO, Institute for SkyWater Harvesting Ltd. Chairman, Skywater Bangladesh (SB) Ltd.
Published in November 2020icon-clockTime to read: 2min 16s

I wanted to help people affected by urban flooding

The Rolex Awards support pioneers who work on creative projects that make the world a better place. In 2002, Makoto Murase received an Award for his “Innovative Sky Water Projects”. His involvement with rainwater harvesting dates back to 1981. At the time, Murase was working as a civil servant at a public health centre in Sumida City, Tokyo, and had concerns about urban flooding.

“That year, we had three torrential downpours, and each time the sewers were flooded by the backflow of excrement-laden sewage. As we went around decontaminating the district, residents told us they wanted us to do something about the flooding. They were desperate, saying that if this kept happening, they wouldn’t be able to continue living there. My speciality is Pharmaceutical Sciences, and civil engineering is outside my field of expertise. But we couldn’t just leave people in such a troubled situation. So, we decided to set up an independent, cross-departmental research group to find out what caused the flooding.”

The backflow of sewage was caused by the fact that more than 70% of the city was covered with concrete and asphalt, which meant that rather than seeping into the ground, rainwater had ended up gushing into the sewers.

“So, we thought the problem could be solved by storing the rainwater in tanks and discharging it into the sewage system at alternate times.” The question then occurred to Murase: how much rain does Tokyo actually get?

Upon researching this question, he discovered that annual rainfall in Tokyo amounted to 2.5 billion tonnes - more than the 2.0 billion tonnes of tap water used annually. At the time, a number of large dams had been built upstream in Tokyo on the basis that there was a lack of water. Meanwhile, the vast water resources at people’s feet was being overlooked. But that’s not all. The construction of huge dams entailed enormous sacrifices for the people living upstream. So, instead of relying on upstream sources of water, shouldn’t Tokyo build multiple small dams within the city to render it self-sufficient in terms of water resources? In this way, the key phrase “If you let it flow, it floods; if you store it, it is a resource” was coined to comprehensively solve the problem of floods and droughts.

“Rainwater harvesting not only provides flood protection in the event of heavy rainfall, but can also be used for domestic purposes in the event of drought or disaster, or on a daily basis to water urban greenery or to flush toilets. I proposed this idea to Sumida City.”

The use of rainwater at the Kokugikan sporting arena, which at the time was attracting worldwide attention, required the understanding of not only the Japan Sumo Association, but also Murase’s managers, the mayor of Sumida City and many others. But his belief in and enthusiasm for the value of the project paid off. In Sumida City, there are now over 650 buildings and houses that use rainwater harvesting, including Tokyo Skytree. The City has literally become a “rainwater city”.

The world’s skies are connected

While working as an employee of the City, Murase responded to requests for inspection tours and was invited to give lectures abroad. He seized every opportunity to share his expertise in rainwater harvesting. At the same time, in cooperation with local residents and the City, he actively promoted the installation of rainwater tanks in alleyways, private homes and public facilities.

In 1994, when Murase was serving as Secretary General, the Tokyo International Rainwater Utilization Conference was held in Sumida City. Attended by a total of 8,000 participants from 18 countries, it bore witness to an immense interest in rainwater harvesting. “Flooding and water shortages are problems faced by cities all over the world. After realising that our rainwater harvesting system could be of use overseas as well, we decided to start an international cooperation project the year after the conference, establishing the NPO People for Rainwater.”

Having visited many different countries and regions, from 1999 he started a full-scale rainwater harvesting social project in Bangladesh, where there were serious issues regarding water. “In Bangladesh, it is not uncommon to find villages with little to no safe drinking water. The water in rivers and ponds is filled with excrement, so diarrhoea is an everyday occurrence if you drink it. Groundwater is contaminated with harmful arsenic. I couldn’t stand by and watch people die from unknowingly drinking clear, colourless, tasteless arsenic.”

Japan is blessed with rain because of the clouds that come from Bangladesh on the Monsoon Asia winds. So, Murase wanted to reach out to the people there as friends under the same sky. Fortunately, Bangladesh receives 2,000 mm of rainfall per year. Moreover, the skies in rural areas are clean, so the water is safe to drink there. “Rainwater is a life-saving blessing from nature. So I started to call it Sky Water.”

The rainwater harvesting system, named AMAMIZU (meaning “rainwater”), collects rainwater from the roof and directs it to a tank. At the end of the downpipe is a flexible elbow, which can be moved in and out of the tank inlet so that only clean rainwater is collected. Local people were trained to manufacture and manage the rainwater tanks, set prices based on villagers’ feedback, and sell them. Over time, the number of buyers increased.

The reason the tanks were not offered free of charge was to create employment for local people and contribute to local industry. “It is very important for us to make the business sustainable and financially independent. We want to use the rain to bring social innovation to the area and eventually create an eco-village that is independent in terms of food and energy.”

The villages saving the world

After retiring, Murase moved to Gotemba City in Shizuoka Prefecture, where his wife grew up. While continuing his work in Bangladesh, he began cultivating a vegetable field with the aim of achieving food independence. For the past nine years, he has been using rainwater for domestic use at home, and has also been working with local people on a project to use rainwater as a means to restore the “satoyama” area between the mountain foothills and flat land. “I have been working in the rainwater harvesting industry for around 40 years, more than half of my life, and now that I am working in the fields I am amazed at the blessings that rain brings. A millimetre of rain is all it takes for green to sprout. I have come to feel that a drop of rain is life itself.”

Murase was involved in the selection of the villages to be included in “SATO – 次世代に残したい里” [The Villages We Want to Leave to the Next Generation], a project run by the Asahi Shimbun and supported by Rolex, which aims to communicate the charms of Japanese villages and the challenges they face.

“The message I sent to the world with my Rolex Award-winning ‘Innovative Sky Water Project’ was ’No more Tanks for War, Tanks for Peace’. Due to climate change, we are now facing a situation where rainfall causes major floods and lack of rainfall causes major droughts, not only in Japan but in many other parts of the world too. Meanwhile, the Earth’s population continues to grow. This could lead to a global food and water crisis in the near future, which in turn could trigger wars. In order to prevent water wars and food wars, and to achieve the SDGs (Sustainable Development Goals) on a global scale, I believe that it is essential for each and every one of us to take a global view of our own lives, and to make our communities more independent in terms of water, food and energy. And I think there are hints of this in villages.”

Villages have a wealth of natural resources, an independent way of life and livelihood supported by them. An appreciation for nature and people is a deep-rooted part of the culture, which has been passed down from generation to generation. It could be said that villages are a perpetual legacy that the Japanese have created over a very long period of time through a mutual support between people and nature.

“The base that supports the structure of the village and the picturesque, unspoilt landscape of the four seasons is the heart of the people. Social innovation starts with one person’s human spirit, something that has also been imparted to the activities that I personally have been doing over many years. At a time when it is becoming increasingly difficult to sustain villages due to an ageing population, I really hope that young people will visit their local areas, see and feel what they are actually like, and think about what they can do to help. For what and for whom do you spend your time living? I’m certain that reflecting on this question will help you to lead a richer life.”

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