Bureau of Reclamation Banner
Great Plains Region
Billings, Mont.
Media Contact:
Coleman Smith
(307) 261-5671

Released On: March 12, 2013

Fluctuation of North Platte River Flow Downstream of Gray Reef Dam
Mills, Wyo. -- The Bureau of Reclamation, at the request of, and in collaboration with, the Wyoming Game and Fish Department (WGF), has scheduled a series of fluctuating flows in the North Platte River downstream of Gray Reef Dam. The purpose of the fluctuations is to improve trout reproduction in the river, according to Coleman Smith, Wyoming Area Manager.

Smith said, "In the past, the spring flushing flows have occurred during five consecutive weekdays. This spring, the Wyoming Game & Fish has requested a duration of 10 consecutive days and the schedule will include two weekends. The Wyoming Game & Fish will collect data before, during, and after the flushing flow in order to evaluate the effectiveness of the longer duration flush".

On March 18-19, The Bureau of Reclamation will evacuate Gray Reef Reservoir to facilitate inspection of the radial gates. Although river flows will remain at the current rate of 500 cubic feet per second (cfs) during this reservoir operation, some fine sediment will be introduced from Gray Reef Reservoir into the North Platte River. Following the gate inspection, Gray Reef Reservoir will be refilled to the normal operating level.

On March 22, 2013, flows in the river below Gray Reef Dam will fluctuate from 500 cfs to 4000 cfs according to the following schedule:

HOURS GRAY REEF OUTFLOWS (cfs)
00:01 to 01:00 a.m. 500
01:00 to 03:00 a.m. 2000
03:00 to 06:30 a.m. 4000
06:30 to 08:00 a.m. 3000
08:00 to 09:00 a.m. 2000
09:00 to 10:00 a.m. 1000
10:00 to midnight 500

This schedule will be repeated daily on March 23 through March 31. After completing the flushing flow on March 31, the flows below Gray Reef Dam will return to 500 cfs.

The flushing flows are expected to clean the spawning gravels of fine sediment which has accumulated over the winter. The fluctuations in the river flow will be achieved without loss of power generation and the water released from Alcova Reservoir will be restored downstream in Glendo Reservoir.

The public is urged to use caution during this period of rapid fluctuation of flows below Gray Reef Dam.

# # #
Reclamation is the largest wholesale water supplier and the second largest producer of hydroelectric power in the United States, with operations and facilities in the 17 Western States. Its facilities also provide substantial flood control, recreation, and fish and wildlife benefits. Visit our website at www.usbr.gov.