Dewater Skiatook and Birch Lakes Stilling Basins, Osage County, Oklahoma

Skiatook Stilling Basin: Contractor will provide all labor, supplies, and materials to successfully stop water from outlet  works and pump water out of Stilling Basin downstream past higher area of channel. A cofferdam will not be required as discharge piping can be placed on the fisherman’s sidewalk serving as a diversion path to the downstream outlet channel. Sidewalk has weep holes and can  be plugged to ensure discharged water continues downstream. A cofferdam will only be needed if a large rain event occurs during the dewater process. All service, emergency, and low flow gates will  be operated by USACE employees and will provide safety lock-out tag-out measures. A 6-in pump with enough suction pipe will be placed in the stilling basin and water will be pumped up the fisherman’s sidewalk. As the stilling basin’s water decreases the use of a smaller diameter pump may be required due to suction issues. A minimum of 3-in pump will be placed where the outlet channel flows away from the stilling basin. All pumps will be supplied by contractor. Coal dust, rags, and cotton seed hulls will be supplied by contractor and inserted upstream of the emergency/service gate to reduce leakage past the gates. This dewater activity is only for inspection purposes and no repairs will be done during this limited time that the stilling basin is open. The govt will provide the contractor with drawings such as plan view of outlet channel, stilling basin, etc.