Shijūshida Dam

The Shijūshida Dam (四十四田ダム, Shijūshida damu) is a dam on the Kitakami River, located in Morioka, Iwate Prefecture on the island of Honshū, Japan.

Shijūshida Dam
Location of Shijūshida Dam in Japan
Official name	四十四田ダム
Location	Morioka, Iwate, Japan
Coordinates	39°45′10.2″N 141°08′54.5″E
Construction began	1960
Opening date	1968
Operator(s)	Iwate Prefecture
Dam and spillways
Type of dam	Concrete gravity dam
Impounds	Kitakami River
Height	50.0 meters
Length	480.0 meters
Reservoir
Creates	Nanbu-Katafuji Lake
Total capacity	35,500,000 m3
Catchment area	1196.7 km2
Surface area	390.0 hectares
Power Station
Operator(s)	Iwate Prefecture
Annual generation	15,100 KW

History

Shijūshida Dam is the fourth in a series of five multipurpose dams built directly on the main stream of the Kitakami River, starting with the Tase Dam in 1941. The project was launched by the Economic Stabilization Bureau in 1947 following Typhoon Kathleen in September 1947 (which killed 1547 people). The need for a dam primarily for flood control was emphasized by Typhoon Ione in September of the following year, which killed an additional 1956 people. The dam was first completed by the Kajima Corporation in 1968.

Design

The Shijūshida Dam was designed as a concrete gravity arch dam; however, since the rocks on both banks were weak, the dam was completed as a hybrid design with earthen dams on the sides and a concrete gravity dam in the center. The project was complicated by the extreme acidity of the water (reaching pH of 4.0) due to runoff from the Matsuo mine upstream. This acidity resulted in the use of special concrete and alloy materials. Generators for the associated hydroelectric power plant produce 15,100 KW of electricity.

References

• Japan Commission on Large Dams. Dams in Japan: Past, Present and Future. CRC Press (2009). ISBN 978-0-415-49432-8
• photo page with data (in Japanese)
• Official home page (in Japanese)