Midono Dam

Midono Dam is an arch dam that curves across the Azusa River in Nagano Prefecture, built to hold back water for power generation and water supply. The structure's curved design distributes water pressure efficiently across the landscape.

This dam was completed in 1969 during Japan's period of rapid infrastructure growth and became part of a broader effort to develop water resources in the Nagano area. Its construction reflected the nation's rising need for electricity after World War II.

This structure is woven into the local landscape and represents engineering that responds to the region's water and energy needs. People in the area depend on it for their daily water supply and electricity.

The dam sits in Nagano's mountain region and requires planning to reach from major cities, as it is located in a remote area. A visit works best during daylight hours when you can see the full structure and the surrounding valley clearly.

The curved shape of the structure is an engineering solution that allows it to hold enormous water pressure using less material than a straight dam would need. This clever design choice made the project more economical and less disruptive to the surrounding landscape.

Location: Inekoki

Inception: 1970

Height: 95.5 m

GPS coordinates: 36.15389,137.74806

Latest update: December 11, 2025 18:11