The is a river in the

Hokuriku region The was located in the northwestern part of Honshu, the main island of Japan. It lay along the Sea of Japan within the Chūbu region, which it is currently a part of. It is almost equivalent to Koshi Province and Hokurikudō area in pre-mod ...

Honshu , historically called , is the largest and most populous island of Japan. It is located south of Hokkaidō across the Tsugaru Strait, north of Shikoku across the Inland Sea, and northeast of Kyūshū across the Kanmon Straits. The island s ...

, Japan. It is also called the Aga River or the Ōkawa River in Fukushima. The source of the river is Mount Arakai on the border of Fukushima and Tochigi. It flows to the north and meets the Nippashi River from Lake Inawashiro and the

Tadami River The is a major tributary of the Agano River in Japan. Its basin covers and its main stem is extensively regulated and developed for hydroelectric power. The river is located within Niigata, Gunma and Fukushima Prefectures. Dams Starting from ...

in the

Aizu is the westernmost of the three regions of Fukushima Prefecture, Japan, the other two regions being Nakadōri in the central area of the prefecture and Hamadōri in the east. As of October 1, 2010, it had a population of 291,838. The princi ...

Basin, and then turns to the west and falls into the

Sea of Japan The Sea of Japan is the marginal sea between the Japanese archipelago, Sakhalin, the Korean Peninsula, and the mainland of the Russian Far East. The Japanese archipelago separates the sea from the Pacific Ocean. Like the Mediterranean Sea, i ...

. The Agano River flows for 210 kilometers. It has a watershed area of 7,710 square kilometers.Archived
3 January 2020 In 1964–1965, a chemical factory at Kanose village in

Niigata Prefecture is a prefecture in the Chūbu region of Honshu of Japan. Niigata Prefecture has a population of 2,227,496 (1 July 2019) and is the fifth-largest prefecture of Japan by geographic area at . Niigata Prefecture borders Toyama Prefecture and ...

released

methylmercury Methylmercury (sometimes methyl mercury) is an organometallic cation with the formula . It is the simplest organomercury compound. Methylmercury is extremely toxic, and its derivatives are the major source of organic mercury for humans. It i ...

into the river and caused Niigata Minamata disease. There are several hydroelectric power plants on the Agano River: * Inawashiro Power Plant (107.5 MW), constructed several steps in 1899–1940. It was the site of the Japan first high-voltage, long-range power transmission line. * Numazawanuma Power Plant (43.7 MW), constructed in 1952. It was the first pumped-storage power plant in Japan. Agano River near Kitakata (3848211488).jpg, Agano River near Kitakata Agano River.jpg, Agano River in Kōnan-ku, Niigata, 5/5/2007

References

External links

* Rivers of Niigata Prefecture Rivers of Fukushima Prefecture Rivers of Japan {{Japan-river-stub