Reclamation will Reduce Crooked River Flows for Stilling Basin Repairs
Media Contact: John Redding, (208) 378-5212
Mark Healy, (541) 389-6541
For Release: September 20, 2007
The Bureau of Reclamation will reduce flows in the Lower Crooked River to between 30 to 35 cubic feet per second in early October to create a safe working environment while crews make repairs to the stilling basin below Arthur R. Bowman Dam located about 18 miles south of Prineville, Ore.
Ochoco Irrigation District, in coordination with Reclamation, is preparing the area for the required dam maintenance that will require dewatering the stilling basin. River flows will be channeled temporarily through a 36 inch bypass pipe until the work is completed in late November.
The work is necessary to repair damage to the concrete deck of the stilling basin as a result of rock debris that has accumulated over time. The repeated churning action from the debris in the stilling basin causes concrete abrasion that threatens the integrity of the stilling basin structure. The dam's stilling basin was last cleaned and repaired in 1987.
Reclamation will coordinate a fish salvage operation with Oregon Department of Fish and Wildlife to relocate any fish stranded in the de-watered area of the river. A qualified biologist will be on-site to assist in fish handling and to obtain records of the fish removed from the de-watered stilling basin area.
"Lower river temperatures and increased canyon shading at this time of the year are expected to mitigate the effect of lower flows on fish populations," said Ron Eggers, Reclamation Lower Columbia Area Manager. "By the end of November, maintenance operations should be complete and normal winter flows will resume in the Crooked River.
Arthur R. Bowman Dam, completed in 1961, is an earthfill structure that stands 245 feet high and impounds Prineville Reservoir on the Crooked River.
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