US Army Corps of Engineers
Portland District Website


Foster project data

Dam length 4,565 ft 1,391.4 m
Height 126 ft 38.4 m
Elevation (NGVD*) 702.5 ft 214.1 m
Lake length 3.5 mi 5.6 km
Area when full 1,220 ac 493.7 ha
*National Geodetic Vertical Datum

Foster hydropower

Generators / total output two 24 mw

Contact Us

General: 541-684-4300
Recreation: 541-942-5631

Foster Dam & Reservoir

Foster Dam and Lake

Foster Dam is located at river mile 38.5 on the South Santiam River, at the confluence of the South Santiam and Middle Santiam rivers, four miles northeast of Sweet Home, Ore.

Foster Dam is a rock-fill structure with a concrete gated spillway, and was completed with Green Peter Dam in 1968 at a cost of $82.3 million.

Foster Dam is used to regulate power-generating water releases from Green Peter Dam and regulate flows from the south Santiam River. Foster Dam has two generators capable of producing 10 megawatts each. Foster Dam works in coordination with Green Peter Dam for flood risk management, hydropower, water quality improvement, irrigation, fish and wildlife habitat, and recreation.

Foster recreation

Day-use parks: Foster Dam has one day-use park operated by the U.S. Army Corps of Engineers. It is open year-round and is free to use. Amenities include vault toilets, picnic tables, barbecue grills and a paved boat ramp with access to the South Santiam River below the dam. For more information, call the Willamette Valley Project Park Ranger Office at 541-942-5631.

Two day-use sites at Foster Reservoir are operated by Linn County Parks: Lewis Creek Park and Sunnyside ParkFor more information call Linn County Parks at 541-967-3917 or visit their website

Boat Ramps: Linn County Parks operates two boat ramps at Foster: Gedney Creek Park and Calkins Ramp. For more information call the Linn County Parks Department at 541-967-3917 or visit their website.

CampingLinn County Parks operates two campgrounds at Foster Reservoir: Edgewater County Park and Marina, and Sunnyside ParkFor more information call the Linn County Parks Department at 541-967-3917 or visit their website.


Environmental stewardship at Foster Dam

The Foster Lake Project covers more than 1,800 acres and provides habitat for several rare species including the northern spotted owl, steelhead and cutthroat trout, Chinook salmon, the western pond turtle and several amphibians.

The Willamette Valley Environmental Stewardship program focuses on restoration of degraded uplands, wetlands and streams on Corps lands. Recent efforts to improve habitat quality for wildlife on Corps lands in these areas center on replacing invasive plants with native trees and shrubs, and restoring hydrology and topography to support native plant communities and wildlife habitat.

To mitigate impacts of Corps dams on Chinook salmon and winter steelhead within the South Santiam River Basin, the Corps constructed the South Santiam Fish Hatchery and a fish collection facility at the base of Foster Dam. Fish collected at the facility are transported back to the hatchery or released above Foster Dam to access upstream spawning habitat. These facilities are operated by the Oregon Department of Fish and Wildlife with funds provided by the Corps. Additionally, the Corps supports ongoing efforts for recovery of the Oregon chub within the South Santiam basin.