High Runoff Expected this Month
Written by Andrew-Rossi on May 11, 2017
BLM Officials have released their May forecast for the summer runoff in this record wet year.
Precipitation totals are at 150 to 160 percent of average statewide, and mountain snowpack across Wyoming is averaging between 125 to 135 percent of normal. Reservoir storages across Wyoming remain above average for May at 125 to 135 percent.
About 20% of the inflow from the Bighorn River into Bighorn Lake occurred in April, leaving about 2.5 million acre feet to flow into the reservoir from May through July. And releases from Yellowtail Dam to the Bighorn River are currently at 13,000 cubic feet per second – BLM officials expect that rate to remain during peak runoff.
The Shoshone River April through July inflow to Buffalo Bill Reservoir is forecast to be 1.25 million acre feet, which is 185 percent of the 30 year average. Less than 10% of that forecasted amount flowed into the reservoir in April, leaving about 1.15 million acre feet to fill the reservoir May through July.
Releases from Buffalo Bill Dam to the Shoshone River are currently at 5,000 cubic feet per second.