BILLINGS, Mont. -- Reclamation's May forecast of the April through July runoff predicted for the Bighorn Basin is as follows:
* Bighorn Lake - Bighorn River April through July inflow to Bighorn Lake is forecast to be 3,057,600 acre-feet (af), which is 280 percent of the 30 year average of 1,093,400 af. Approximately 603,400 af of the forecasted amount flowed into Bighorn Lake during April, leaving approximately 2,454,200 af of inflow forecasted for May through July.
* Releases from Yellowtail Dam to the Bighorn River are currently 13,000 cfs. Based on the current operating projections and the expectation of record runoff, Bighorn Lake will be managed to fill to an elevation of 3640.0 feet. During peak runoff, releases from Yellowtail Dam to the Bighorn River are expected to be above 13,000 cfs.
* Buffalo Bill Reservoir - Shoshone River April through July inflow to Buffalo Bill Reservoir is forecast to be 1,250,000 af, which is 185 percent of the 30 year average of 677,200 af. Approximately 95,800 af of the forecasted amount flowed into Buffalo Bill during April, leaving approximately 1,154,200 af of inflow forecasted for May through July.
* Releases from Buffalo Bill Dam to the Shoshone River are currently 5,000 cfs. Based on the current operating projections and the expectation of record runoff, Buffalo Bill Reservoir will be managed to fill to an elevation of 5391.50 feet. During peak runoff, releases from Buffalo Bill Dam to the Shoshone River are expected to be above 5,000 cfs.
* Wind River - April through July snowmelt runoff into the Wind River above Bull Lake Creek is expected to be 800,000 af, which is 201 percent of the 30 year average of 398,100 af. Approximately 34,600 af of the forecasted amount was received during April, leaving approximately 765,400 af of inflow forecasted for May through July.
* Bull Lake Reservoir - April through July snowmelt runoff into Bull Lake Reservoir from Bull Lake Creek is expected to be 250,000 af, which is 184 percent of the 30 year average of 136,000 af. Approximately 10,300 af of the forecasted amount flowed into Bull Lake during April, leaving approximately 239,700 af of inflow forecasted for May through July.
* Boysen Reservoir - Wind River April through July inflow to Boysen Reservoir is forecast to be 1,500,000 af, which is 278 percent of the 30 year average of 540,000 af. Approximately 132,800 af of the forecasted amount flowed into Boysen during April, leaving approximately 1,367,200 af of inflow forecasted for May through July.
* Releases from Boysen Dam to the Wind River are currently 5,500 cfs. Based on the current operating projections and the expectation of record runoff, Boysen Reservoir will be managed to fill to an elevation of 4724.50 feet. During peak runoff, releases from Boysen Dam to the Wind River are expected to be well above 5,500 cfs.
For additional information on Buffalo Bill, Wind River, Boysen, and Bull Lake Reservoirs, contact Wyoming Area Manager Carlie Ronca at 307-261-5671. For additional information on Yellowtail Reservoir, contact Montana Area Manager Steve Davies at 406-247-7298.
Source: Bureau of Reclamation
