Bonneville Dam - Dimensions and Statistics

Dimensions and Statistics

• Owner: U.S. Army Corps of Engineers, Portland District
• Location: On Columbia River about 40 miles upstream from Portland, Oregon
• First Powerhouse – Constructed in 1933-37; Dam 313 m (1,027 ft) long x 77 feet (23 m) high forebay; 10 generators with a nominal total output capacity of 526.7 MW; Overload capacity 577 MW.
• Spillway – Constructed 1933-37; 18 gates over a length of 442 m (1,450 ft); maintains the reservoir (upriver) usually 18 m (59 ft) above the river on the downstream side;
• Second Powerhouse – Constructed 1974-82; Dam 300.5 m (986 ft) long x 77 feet (23 m) high forebay; 8 generators (plus two at fish ladders) with a nominal total generating capacity of 558.2 MW; Overload capacity 612 MW.
• Bonneville Lock – Constructed from 1987 to 1993 at a cost of $341 million; 26 m (85 ft) wide, 206 m (676 ft) long; transit time is approx. 30 minutes. Replaced earlier smaller lock built 1938.
• Lake Bonneville – 77 km (48 mi) long reservoir on the Columbia River created by Bonneville Dam; part of the Columbia-Snake Inland Waterway.

It was declared a National Historic Landmark in 1987.