Ōi River

The Ōi River flows from the Akaishi Mountains, the branch of the Japanese Southern Alps which form the border between Shizuoka, Nagano and Yamanashi prefectures.

[1] These mountains, with peaks ranging from 2,000 to 3,000 metres (6,600 to 9,800 ft), are characterized by heavy rainfall (up to 3,000 millimetres (120 in) per year) and deep V-shaped valleys.

In cases of bad weather or high waters, they were forced to stay several days (or even several weeks) beside the river at post stations such as Shimada-juku or Kanaya-juku.

During the early 1930s, Ōigawa Electric had completed a number of dams on tributary branches of the Ōi River, but work was stalled by the Great Depression, and came to a halt during World War II.

After the end of World War II, the American occupation authorities ordered the dissolution of Nippon Hassoden, which was divided into regional power companies.

Travellers Crossing the Ōi River by Hokusai