2013 AWRA Annual Water Resources Conference
Field Trip


Field Trip #2: Columbia River Gorge to Historic Bonneville Dam


November 3, 2013
12:30 PM to 5:30 PM
Cost: $33.00
Register by: 10/14/13

Description of Activities:

The trip will start by traveling upriver (east) on I-84 following the Lewis and Clark trail along the Columbia River and into the scenic Columbia River Gorge to historic Bonneville Dam. Beautiful Multnomah Falls will be the first stop, where participants can stretch their legs and purchase refreshments.

Bonneville Dam MapMultnomah Falls is the tallest waterfall in the State of Oregon, with a total height of 620 feet in two separate drops. Underground springs from Larch Mountain are the year-round source of water for the waterfall, augmented by spring runoff from the mountain's snowpack and rainwater during the other seasons. A foot trail leads to Benson Footbridge, a 45-foot (14 m)-long footbridge that allows visitors to cross 105 feet (32 m) above the lower cascade.

Bonneville Dam and Lock is a concrete, gravity dam consisting of several run-of-the-river dam structures that together complete a span of the Columbia River between Oregon and Washington states at River Mile 146. The dam is located 40 miles (64 km) east of Portland, Oregon in the Columbia River Gorge. The primary functions of Bonneville Lock and Dam are electrical power generation, fish passage and river navigation. The dam was built and is managed by the U.S. Army Corps of Engineers. Electrical power generated at Bonneville is distributed by the Bonneville Power Administration. Bonneville Lock and Dam is named for Army Capt. Benjamin Bonneville, an early explorer credited with charting much of the Oregon Trail.

A Public Works Administration project of President Franklin D. Roosevelt's New Deal, portions of Bonneville Dam were designated a National Historic Landmark District in 1987. The project's first powerhouse, spillway and original navigation lock were completed in 1938 at a cost of $88 million to improve navigation on the Columbia River and provide hydropower to the Pacific Northwest. A second powerhouse was completed in 1981 at a cost of $664 million, and a larger navigation lock was constructed in 1993. The total rated capacity of both powerhouses is 1084 MW.

Construction of Bonneville Dam blocked the migration of white sturgeon to their upstream spawning areas. Sturgeon still spawn in the area below the dam and the lower Columbia River supports a harvestable sturgeon population. Small, depressed populations of white sturgeon persist in the various reservoirs upstream. To address anadromous fish migration problems, the dam features fish ladders to help native salmon and steelhead get past the dam on their journey upstream to their spawning grounds. Elevation gained up the Bonneville fish ladders is 60 feet (18.3 m).

For additional information and a fact sheet about Bonneville Lock and Dam please visit the following site: http://www.nwp.usace.army.mil/Locations/ColumbiaRiver/Bonneville.aspx.