McPhee Reservoir managers announced Friday that the forecast calls for a whitewater release below McPhee Dam.

“The forecast shows a 22-day whitewater season,” said Bureau of Reclamation engineer Vern Harrell. “But it is a 50-50 probability, so it is not guaranteed it will materialize.”

Based on this year’s impressive snowpack in the mountains, runoff forecasts show the reservoir will fill, and there will be 68,000 acre-feet available for a spill into the lower Dolores River.

Here is the plan if the snowpack holds:

On May 17, flows below the dam would be increased to 500 cubic feet per second. It would ramp up to 900 on May 18, then 1,300 cfs on May 19, and 1,500 cfs on May 20.

From May 21-25, the plan is to max out the flows at 2,000 cfs, then they will drop slightly to 1,800 cfs from May 26 to June 1 for the Memorial Day weekend.

On June 2 flows will be reduced to 1,400, cfs, drop 1,000 cfs on June 3, to 800 cfs on June 4 and 5, to 600 cfs on June 6 and 7, to 400 cfs for June 8 and 9, then 200 cfs for June 10 and 11.

Minimal rafting flows is 600-800 cfs, and for kayaks it is 300-400 cfs. Tubing could be done at 200 cfs.The boating community is excited, but cautious, said Josh Munson, vice president of the Dolores River Boating Advocates.

“We remain hopeful, but know the weather controls everything,” Munson said. “The forecast for a spill is exciting, but if temperatures rise, the chances of a release could be affected.”

There has not been a whitewater release below the dam since 2011.

The surge of water into the lower canyon will benefit the natural environment, Munson said, and create an economic boon to the area as recreational boaters descend to the various launch sites.

“It would be awesome,” he said.

jmimiaga@the-journal.com