Hatanagi-I Dam

Hatanagi-I Dam is a gravity dam on the Ōi River in Shizuoka Prefecture that stands about 125 meters tall. The facility operates as both a power generator and a pumping station, using reversible turbines to manage water flow based on energy needs.

Construction started in the 1950s as part of Japan's post-war infrastructure development, supported by international funding. The project reflected growing demand for reliable energy sources during the nation's rapid economic expansion.

The Hatanagi-I Dam represents Japan's early recognition of hydroelectric potential, following initial design work by the Japan Electric Generation and Transmission Company in 1902.

The site is accessible by local roads that wind through the surrounding mountains. Visitors should expect that many large infrastructure facilities like this have limited public access, and viewing may be from a distance.

Water travels through a 5-kilometer tunnel to reach a second dam downstream, creating an interconnected system. This setup allows the same water to be used multiple times for power generation as it circulates between the reservoirs.

Location: Shizuoka Prefecture

Inception: 1957

Height: 125 m

Part of: Hatanagi dams

GPS coordinates: 35.32167,138.18333

Latest update: December 8, 2025 19:53