Sustainable Sewage Management

Sustainable Sewage Management

The sewage system of Yokohama City almost fully covers its large territory with more than 3.5 million population. The length of sewer pipes is about 11,000 km in total, equivalent to the distance between Yokohama City and New York City, USA. The city’s 11 wastewater treatment plants constructed between 1962 and 1984 daily treat about 1,500,000 m3 of waste water. The sewage system has been addressing sustainability challenges in resource efficiency, reduction of greenhouse gas (GHG) emissions, and reduction of flood risk in the context of an aging society and national resilience. It also adopted advanced treatment technologies in pursuit of improved sanitary conditions and water quality in rivers and streams.