Idaho Panhandle Chapter: Colburn Creek, Idaho

Colburn Creek flows freely after the removal of an old milldam. The dam's removal opened more than 3 miles of spawning and rearing habitat for westslope cutthroat trout, kamloops rainbow trout, and perhaps the federally threatened bull trout. (Crown Pacific Partners, L. P. photo)

Colburn Creek is a tributary to Lake Pend Oreille, the largest lake in Idaho. While the creek once provided spawning habitat for migratory trout, such as the west-slope cutthroat, in the 1940s a small dam was constructed to power a mill. The 12-foot high, 35-foot long structure blocked fish passage and created an impoundment that became choked with sediment.

Crown Pacific, a major forest products company in the western United States, purchased the mill and surrounding 90 acres in 1993. Over time, the aging mill proved to be inefficient, and the company closed operations at the site in 1999. Crown Pacific chose to significantly improve the area as they pulled out their operation, and at the suggestion of the Idaho Department of Fish and Game (IDFG) decided to remove the milldam.

Panhandle Chapter volunteers install fish habitat enhancements in a culvert. The restoration work is expected to help open up spawning and rearing habitat for migratory trout. (Panhandle Chapter photo)

Crown Pacific invited the Panhandle Chapter of Trout Unlimited to provide information and participate in restoration work at the site. The Panhandle Chapter collaborated with the company and the IDFG to remove the dam and make improvements to the riparian areas and wildlife habitat around the site. Improvements included enhancing wetlands, planting trees and grass to buffer the stream channel, providing nest boxes for waterfowl, and installing fish ladders where the gradient was too steep for fish at high flows. For one of the fish ladders, Panhandle Chapter volunteers installed the ladder and split the cost of materials with Crown Pacific.

The close collaboration of the site owner, the state, and TU volunteers was significant to the success of the restoration project. The removal of Colburn Mill Pond Dam opened more than 3 miles of spawning and rearing habitat for west-slope cutthroat, kamloops rainbow trout, and perhaps the federally threatened bull trout.