Abstract
In the Hida River, hydroelectric resources have been developed for many years and there are many dams with a reservoir operating for power generation. Turbid water which has seemed to be resulted from the land development as well as the dam construction in this river basin has caused various problems. A localized heavy rain in 1958 caused the long-term persistence of turbid water, which developed a social and political problem. After that, a selective withdrawal equipment was introduced and the operational method of the dams was improved, which enabled to lighten the problem. This paper describes the details and future plan against the turbid water problem.
