Satunaigawa Dam web site（Purpose of Satunaigawa Dam - Maintenance of River Discharge）
Purpose of Satunaigawa Dam
Maintenance of River Discharge
Satsunaigawa Dam proved its ability to prevent flooding caused by heavy rain in August 1997 when the dam was in the flooding test stage. About 640m3/s of water accumulated, of which 80m3/s was discharged and 560m3/s was retained. The maximum flow of water downstream of the dam at Nantaibashi Bridge was about 600m3/s. Without the dam, the flow of water would have been about 1,000m3/s, more than the all-time high recorded during a flood in August 1981. This experience showed that the Satsunaigawa Dam prevents flooding and protects areas along the upper and midstream sections of the Satsunaigawa River.