Otagiri Dam

Overview

Otagiri Dam is a hydroelectric dam built on the Sai River, part of the Shinano River system, in Nagano City, Nagano Prefecture. It is a gravity concrete dam standing 21.3 meters high and is managed by TEPCO Renewable Power. Its total storage capacity is about 2,546,000 cubic meters, and the stored water is sent downstream to the Otagiri Power Station, generating up to 16,900 kilowatts of electricity. Rather than a showy tourist dam, it is a place where you can feel the river and the power facility up close. Please check official information for whether visits are allowed and for local rules.

Highlights

• ●A 21.3-meter gravity concrete dam on the Sai River of the Shinano system
• ●An active hydroelectric facility generating up to 16,900 kilowatts
• ●A reservoir with a total capacity of about 2,546,000 cubic meters
• ●A structure built in 1953 that carries the history of hydropower

History

Otagiri Dam is a relatively old hydroelectric dam begun and built in 1953, and English sources also record its completion in 1954. It was created to turn the water power of the Sai River in the Shinano River system into electricity, and today it operates as a generating dam under TEPCO Renewable Power. It is one of the facilities that carries on the history of hydroelectric power that supported Japan's period of rapid economic growth.

Map

36.6200, 138.1231 · Wikidata

Suggested itinerary

1. 1Follow the Sai River from central Nagano up to Otagiri Dam
2. 2View the dam body and reservoir and picture how hydropower works
3. 3Enjoy the seasonal scenery of the Sai River gorge
4. 4Return to central Nagano for a stroll around Zenkoji Temple

Did you know?

💡 At 21.3 meters, the dam is small compared with large-scale dams, yet it is an active power facility generating up to 16,900 kilowatts. The name is read Otagiri, and it is also written Odagiri in English, so its reading varies, which is one distinctive point of this dam.

Nearby spots