Japan's largest drainage pump station (Japan)
Protecting Japan from floods with large drainage pump stations called giant underground water tanks
Japan is a country prone to flooding due to high precipitation and steep-banked rivers. Moreover, due to the effects of climate change associated with global warming, the frequency of heavy rain and short bursts of strong rain, as well as the amount of precipitation, are projected to increase further in the future, raising concerns about large-scale flood disasters. As a countermeasure, EBARA has been delivering pumps to domestic drainage pump stations in cooperation with the Ministry of Land, Infrastructure, Transport and Tourism and local governments, boasting the highest market share.
Showa Drainage Pump Station is like an underground water tank (the Metropolitan Outer Area Underground Discharge Channel).
The facility called the Metropolitan Outer Area Underground Discharge Channel, which directs water from the rivers when they are swollen due to heavy rain into an underground tunnels for discharge into the Edo River, is located approximately 50 m underground in Kasukabe City, Saitama Prefecture. This is one of the world’s largest underground flood water diversion facilities with a diameter of 10.6 m and a total length of 6.3 km. Water collected from the rivers during heavy rain goes through a pressure-adjusting water tank, such as a giant underground water tank, and then it is pumped and discharged into the Edo River by EBARA’s four huge pumps. When the four pumps are operating, they can drain 200 tons of water per second and pump the water to a height of a four-story building (approximately 14 m). The largest amount of water discharged to date was during a typhoon in 2015, and was equivalent to 15 Tokyo Domes.
Photo courtesy of Edogawa River Office, Kanto Regional Development Bureau, Ministry of Land, Infrastructure, Transport and Tourism
Kema Drainage Pump Station boasting one of Japan's largest pumps
Located on the Okawa River, which branches off from the Yodo River, a first-class river near Osaka Bay, the Kema Drainage Pump Station was built in the 1970s to prevent flooding during high tides and heavy rainfall, and has continued to protect the surrounding urban area and other communities. Construction work is currently in progress to ensure it remains useful for years to come. This drainage pump station has six large-scale pumps equipped with 4 m diameter impellers. These pumps can adjust the flow rate by changing the angle of the impeller during operation.
Shinkawa-kako Drainage Pump Station protects fields and local communities from flood disasters.
The Nishikanbara region of Niigata Prefecture is located in the center of the Niigata Plain, is a low marshy area where approximately 20% of the land is below sea level, and was at a constant risk of overflowing due to poor drainage and flooding. For this reason, the Shinkawa-kako Drainage Pump Station was built in 1970 to reduce the water level of the Shinkawa River, with the aim of improving drainage from subsided farmland and achieving stable agricultural production. This drainage pump station uses six large-scale pumps equipped with 4.2 m diameter impellers. These pumps can adjust the flow rate by changing the angle of the impeller during operation. Renewal work was carried out from 2007 to 2015, which improved reliability and significantly improved maintenance and management operations.
