Lake Tazawa ASI-244

Riparian Nation(s) Japan
Surface Area 26 km2 Mean Depth 280 m Volume 7 km3
Shoreline Catchment Area 47.8 km2 Residence Time 7.3 yr
Frozen Period Mixing Type Morphogenesis/Dam
Related Info/Site


Lake Tazawa is a caldera lake located to the west of Mt. Komagatake in Akita Prefecture. It is the deepest lake in Japan. Once oligotrophic lake water turned to acidic when a war regime introduced the highly acidic water from Tamagawa Hot Spring in 1940 for power generation and irrigation. Although the Japanese Government constructed a neutralization facility in 1989 full neutralization of the lake is not achieved yet.