So when the rain falls, the overloaded and overflowing sewage system gives floods. Some 16 years ago, a serious flood inflicted heavy financial and health losses in Sumida City, one of the most densely populated wards in Tokyo. Floodwaters inundated many of the ward's buildings with sewage-contaminated water. For weeks people had no drinking water, as the city's drinking water tanks are installed underground. The situation piqued Murase, who was then working in the public health centre of the local municipality, to find ways to utilise rainwater.
Rain is an incredibly important resource.
This not only reduces the city's water demand and reduces the pressure on water supply but also saves the environment. Large tracts of farm and forest land that large dams devour are also spared. Moreover, rainwater is free. Its users save money. The civil servant thinks Tokyo is an ideal situation to reap the benefits of collecting rainwater as it is covered in concrete.