Mountain States Construction Company - Arrowrock Dam Hydroelectric Facility

Arrowrock Dam Hydroelectric Facility

18 MW Hydroelectric Facility

Boise, Id

The powerhouse houses two 9 MW turbines.  These two turbines are producing more than 9 MW each as installed and tested and have a life expectancy of over 50 years.  Annual generation is over 90,000 MWh.

The powerhouse is 68 feet in diameter and 85 feet tall from the base rock foundation to the roof; 19,000 cy of basalt was drilled and blasted to facilitate the structure and penstocks which have over 6,000 cy of concrete and over 700,000 lbs of reinforcing steel.

The powerhouse is located 23 miles Southeast of Boise, Idaho on teh Boise River at the base of the Arrowrock Dam and within the Lucky Peak Lake.  Construction of the powerhouse had to be constructed during a 6 month winter draw down of Lucky Peak and brought above high water elevations for summertime flows.

This project was completed under an EPC contract format.

Owner: Boise-Kuna, New York, Nampa & Meridian, Wilder, and Big Bend Irrigation Districts

Click on the photos below for a larger view.

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