Japan’s period of postwar recovery brought about urbanization and lifestyle changes across the country. Furthermore, industrial development associated with the ensuing period of rapid economic growth led to a sharp rise in water pollution, something which became a major social issue at the time. The Water Pollution Prevention Act was enacted in 1970 in response to this situation. Under this law, the role of sewerage systems was defined as a means to preserve water quality in public water areas. Regulations concerning the preservation of water quality were subsequently tightened, and the Sewerage Act was revised in 2005 in an effort to promote advanced treatment methods for sewerage systems. It was against this backdrop that the first sewage treatment plant employing Kubota’s advanced wastewater treatment technology came into operation in Fukusaki Town, Hyogo Prefecture, Japan.

In 1993, Fukusaki, a town blessed with a rich climate and historical heritage, set out its plan to construct Fukusaki Wastewater Treatment Plant in an effort to improve the living environment of its residents and conserve the natural environment of the Ichikawa River, which flows through the center of the town. This plan called for the preservation of water quality, with consideration given to the water purification plants located downstream that use water from the Ichikawa River, where treated water from Fukusaki Wastewater Treatment Plant would be discharged, as the source of their water supply. Fukusaki initially planned to adopt a sewage treatment method that was economical and easy to maintain. However, eight years after the announcement of the plan, the town decided to reconsider its options in terms of the kind of treatment technology that it would adopt. As a result, the town found out about MBRs, which offer a higher level of treated water quality than conventional treatment methods, yet allow for downsized facilities. The town adopted a method of water treatment using MBRs based on submerged membranes,^*2 Kubota’s proprietary membrane technology, because it complies with water quality regulations that were tightened to prevent eutrophication in the Seto Inland Sea,^*3 into which the Ichikawa River flows, and because it is expected to reduce project costs through effective land use and downsized facilities by drastically reducing the size of the site needed to house treatment facilities.^*4 As a result, Fukusaki Wastewater Treatment Plant became the first MBR facility in Japan’s public sewerage system, attracting attention from various quarters, including local government officials and the media.

Kubota had been researching water treatment utilizing MBRs since the late 1980s. Our MBR technology soon came into the limelight in Europe, where strict regulations had been put in place to improve water quality, and was adopted by a sewage treatment plant in the UK, which was in need of a system that could provide advanced secondary treatment of sewage without using chlorine. MBR technology was originally designed to meet the needs of the UK and other European countries, and has since been adopted by sewage treatment facilities in Japan, the US, the Middle East, and other countries. This technology that cleans sewage and returns it to nature has further developed into a technology that recycles the cleaned water as a resource. Today, it is used in a wide range of applications around the world, such as sewage and industrial wastewater treatment, and has been installed in more than 6,000 across the globe. Kubota is committed to protecting our planet’s finite resources and contributing to the regeneration and supply of water that can be used with peace of mind by people the world over.