Dam Removal & Diversion Structure Installation, Calapooia River, Brownsville, Oregon

Client: Cascade Earth Sciences, Calapooia Watershed Council

The Brownsville Dam was removed by Northwest Biological Consulting during the summer of 2007. The dam was an old reinforced concrete dam that served to divert irrigation water into the Brownsville Canal. The 110 foot dam spanned the Calapooia River which is an important river for Chinook Salmon and Steelhead Trout populations. The dam was a significant migration barrier to anadromous fish. Permits from the Army Corps of Engineers were obtained and consultation with NOAA Fisheries and other agencies was completed prior to construction activities. Coffer dams, turbidity curtains, silt fences, pumps, water quality sampling and other BMP's were employed during the dam removal to minimize turbidity and maintain water quality standards stipulated in the permits. After the dam was removed the river channel was graded to match the surrounding riverbed morphology. The dam removal project received an outstanding achievement award from the Governor.

A pump station and fish screen was installed as the second phase of the project, and was completed during the summer of 2008. The pumping facility will provide a small amount of irrigation water to the Brownsville Canal. The fish screen was constructed as part of the pump intake to prohibit fish from being sucked into the pump impeller.