What kind of rafting season can boaters expect?

A short whitewater rafting release is “probable” for the lower Dolores River canyon this month, according to water officials.

Beginning May 20, the Dolores Water Conservancy District expects to release 800 cfs from McPhee Dam into the lower canyon for an estimated 10-day period. The release is scheduled to coincide with Memorial Day weekend, May 28-30.

Recent rain and snowpack monitors showing a healthy water content above 9,000 feet elevation “bodes well for solidifying the most probable forecast, which remains. . . a ten-day release . . around May 20,” according to the DWCD website’s update April 26.

A below-average winter snowpack for the Dolores River Basin is limiting the rafting season this year, reports DWCD general manager Mike Preston. “But the good thing is that going into last fall, the starting reservoir level was higher than the previous year and that improves the prospect for a small spill” this spring despite the marginal winter, he said.

As of April 26, the reservoir is forecasted to fill, and no shortfall is expected for irrigation demands, Preston said. During low snow years such as this one, managers are careful to practice a “fill-and-spill” strategy with the reservoir, making sure it fills to capacity first before any boating releases are considered so that irrigators may receive their full shares of water for the agricultural season.

Once full at 380,000 acre-feet, extra runoff from the upper Dolores River may be allowed to pass through the reservoir and spill into the famed Dolores River Canyon, a scenic and popular rafting destination.

Boating the desert/mountain canyons of the lower Dolores River does not require a permit. The river is considered intermediate with rapids at Classes 2-4 on a scale of 1 through 6, with 6 representing unrunnable and 1 being a ripple.

Snaggletooth Rapid, at Class 4, is the most formidable and is located eight miles below the pumphouse. Stateline Rapid, at the Colorado-Utah border, is also a very challenging whitewater section.

A popular local day trip is the 18-mile Ponderosa Gorge, from Bradfield Bridge (4 miles below McPhee dam) to the Dove Creek Pumphouse (continuous Class 2-3 rapids). Multi-day trips from Slickrock to Bedrock, a 50-mile stretch into remote wilderness, are also ideal for river adventure and the section does not exceed Class 3 rapids.

Whitewater releases are subject to change based on weather, rate of runoff and irrigation demand, officials warn. Hot weather, high winds, dust, dry mountain-soil conditions and high irrigation demand could quickly diminish mountain snowpack and erase the extra water for the whitewater spill. Or cooler weather, rain, moist soil conditions and lower irrigation demand may sustain runoff volume that is above reservoir capacity and help to extend the rafting season slightly.

“Mother Nature is driving the train,” Preston said, adding that “small spill years such as this one are the most difficult to manage.”

Keep apprised of the most up-to-date forecast for boating releases at doloreswater.com. Click on “releases” for current information

From May 2011. Read similar stories about , .