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Engineers set to lower water at Bowman-Haley Dam

The Omaha District of the U.S. Army Corps of Engineers will draw down Bowman-Haley Reservoir approximately 2.4 feet to pool elevation 2747.5 feet for maintenance on the reservoir gates.

Posted on August 24, 2012

Releases will be initiated on Aug. 22 with the maintenance scheduled to begin the week of Sept. 10. Bowman-Haley Reservoir is located about 15 miles southeast of Bowman, N.D., in Bowman County.

Bowman-Haley Reservoir is currently at 2749.9 feet with 62 percent of the multi-purpose pool occupied. While there currently are no releases from the reservoir, the pool elevation is dropping at approximately 1 inch per week due to evaporation. The drawdown to elevation 2747.5 feet is 7.3 feet below the top of the multi-purpose pool resulting in 49 percent of the multi-purpose pool occupied. The drawdown will result in lake levels similar to the record low of 2747.6 feet reached during drought conditions in 1992.

Releases will be at 140 cubic feet per second. It will take approximately 2 weeks to complete the drawdown. During this time, residents on the North Fork Grand River downstream of Bowman-Haley Reservoir will see some higher flows along the river, resulting in a stage increase of about 2 feet at the North Fork Grand River near the White Butte, S.D., river gage. Downstream on the Grand River, the U.S. Bureau of Reclamation will be making small releases at Shadehill Reservoir to perform a shoreline stabilization project.

With the reduced pool elevation, the Corps will be able to address ice damage from the last several years to the low level gate. Some parts of the gate will be replaced and a new ice shield installed to prevent future damages.

Normal precipitation events will be used to refill the reservoir. The reservoir could fill in one large rainfall event as occurred in 1992 following the record low. Continuing drought conditions may prolong the length of time needed to restore the full multi-purpose pool. Current predictions place the refilling of the lake between 8 and 21 months.

River stages on the Grand River in South Dakota are available on the U.S. Geological Survey website at waterdata.usgs. gov/sd/nwis/current/?type=flow. Reservoir levels at Bowman-Haley Reservoir can be viewed at www.nwd-mr.usace.army. mil/rcc/plots/jpegs/boha.jpg.