Too much water released for forecasted runoff
Blue Mesa Reservoir is not expected to fill this summer, despite the predictions of water officials earlier this spring.
During a regular meeting of the Upper Gunnison River Water Conservancy District (UGRWCD) on Monday, June 24, district manager Frank Kugel said the actual runoff entering the reservoir would fall short of Colorado River Forecast Center projections. “As it stands, we’re not going to fill Blue Mesa,” he said.
Kugel says the Bureau of Reclamation, which is responsible for operating Blue Mesa Dam, is now expecting the reservoir pool to peak about nine feet short of full. “That nine feet contains roughly 80,000 acre feet of water,” he said after the meeting.
Kugel says the water shortage, “has a significant impact on recreational opportunities,” and could also complicate potential calls for additional water at the Redlands Power Canal, a canal that diverts water from the Gunnison River for power production near Grand Junction. “Upper basin storage is a valuable thing to this community,” he says.
“The (Bureau of Reclamation) is very disappointed that they did not hit the full level and released more water than necessary,” Kugel said at the meeting.
UGRWCD member Ken Spann said the amount of water that would be missing from Blue Mesa is comparable to the entire amount of water in Taylor Park Reservoir. However, Spann conceded that the task of forecasting spring runoff is very difficult.
Earlier this spring the forecast from the Colorado Basin River Forecast Center called for over one million acre-feet of water to flow into Blue Mesa between April 1 and July 31. One acre-foot of water could cover a football field to a depth of six inches.
According to Bureau of Reclamation water resources group chief Dan Crabtree the bureau bases its management of Blue Mesa and the Aspinal Unit (Blue Mesa, Morrow Point and Crystal Dams) on runoff forecasts provided by the Colorado Basin River Forecast Center, a branch of the National Weather Service.
Crabtree says the River Forecast Center begins forecasting spring and summer runoff in January each year.
“We design our operations based on their forecasts. Sometimes we hedge a little bit toward it being drier, or it being wetter. This year we hedged a little bit toward the drier side, but stayed close to their predictions,” Crabtree says. “They are still confident we’re going to get a lot of water in July… We’re not quite as confident as they are.”
Colorado Basin River Forecast Center hydrologist John Lhotak says fluctuating temperatures this spring could still leave enough water stored in the high country snow pack to fill Blue Mesa. “We’ve been getting warm ups, but also cool downs. It’s been holding the snow back a little later in the season,” he says.
Lhotak says there is room for error in the late winter and early spring forecasts from the Center. “When we do forecasts that far out, a lot of what we forecast on is climatology. We’re assuming there will be average precipitation and average temperatures. If we don’t get average precipitation or temperature it has a big effect,” Lhotak says.
2008 is not the first year that the River Forecast Center has overshot runoff projections. “This is a disturbing trend we’ve had for the last few years,” Kugel said.
Board member Steve Glazer agreed it was becoming a recurring problem. Glazer believed there were two things affecting the forecasts, the first being the sheer geographical size of the runoff area the River Forecast Center has to consider. The second problem was a limited amount of data being collected, Glazer said.
He asked how many snow-pack monitoring sites were being analyzed in the Upper Gunnison Basin.
Kugel said there were about six SNOTEL (snow telemetry) sites, and five snow monitoring courses in the basin.
Glazer asked if the UGRWCD should make a recommendation to the National Weather Service to install more snow monitoring sites. “More data points are needed. We have to organize and get our congressional delegation to appropriate money to that purpose,” Glazer said. “There’s insufficient data there.”
Board member Ralph Grover agreed and said additional monitoring could also be useful in the Lake Fork area of Hinsdale County.
Board member Gary Hausler recommended that the UGRWCD Special Projects Committee look for solutions and ways to get more monitoring and then report back to the board.
Lhotak agrees that additional snow pack monitoring could help with forecasting. “If we have data gaps in how much snow that is out there that also contributes to error,” he says. Lhotak agrees that areas south of Blue Mesa and near Lake City were in need of additional monitoring. “That’s not so say we couldn’t use more up by Crested Butte and that area.”
In other waterway news, Kugel said the UGRWCD-owned Meridian Lake Reservoir is currently full and safely spilling.
Kugel said the runoff entering the Taylor Park Reservoir was also coming in lower than earlier forecasts, and releases from that reservoir were being cut back to ensure an adequate fill.
Earlier during the meeting, Gunnison District Court Chief Judge Steven Patrick administered the oath of office for the UGRWCD’s new and returning board members. Gunnison representatives Diane Lothamer and Bob Drexel resigned from the board last month, and Gunnison residents Bill Nesbitt and Jim Pike have been appointed to take their place. Taylor River area resident Ken Spann is continuing service on the board for another term.