The Hisayoshi Dam (久吉ダム, Hisayoshi damu) is a dam located in the city of Hirakawa, Aomori Prefecture in the Tohoku region of Japan. The dam is a concrete gravity dam across the Hirakawa River, a tributary of the Iwaki River. Construction on the dam was begun in 1980 by a consortium led by the Obayashi Corporation, and the dams as completed in 1995. across the Kodomari River. It is a multipurpose dam to provide water for irrigation, flood control and drinking water.