Snowpack news

A picture named snowflakesbentley.jpg

From the Delta County Independent: “Prior to the short storm that passed through the area Monday and early Tuesday, area snowpack had declined from 102 percent of average to 95 percent of average the previous week, reports Rob Fiedler, emergency preparedness coordinator. Warm temperatures and winds are blamed for the recently declining snowpack levels. ‘It looks like we won’t be needing to order sandbags for flood control this spring,’ Fielder said.”

From the Aurora Sentinel: “Aurora Water department data from the beginning of March shows levels from the Upper Colorado at 105 percent, levels from the South Platte at 94 percent and levels from the Arkansas at 96 percent of the yearly average. As of Monday, March 2, the city’s reservoirs were at 72 percent of their capacity.”

From the Pikes Peak Courier View: “Even though the average snowpack for the Arkansas River basin is 112 percent of normal, locally snowpack in the Trout Creek basin is about 4 inches lower than its 30-year average for March 1 of 18 inches. According to information provided by Colorado Springs Water Department, the Pikes Peak watershed reservoir sits at 70.6 percent of the 30-year average. The Northfield area reservoir is 76.9 percent of normal. Reservoir storage at South Suburban and Goldcamp is 75.6 percent of normal.”

From the Estes Park Trail Gazette (John Cordsen):

Precipitation and snowfall in the first two months of 2009 in Estes Park is running slightly behind last year’s totals. Through February 2008, Estes Park had seen 19.9 inches of snow, which equated to 1.14 inches of precipitation. Through February 2009, snowfall is at 18.1 inches, or 1.01 inches of precipitation.

Snowpack for the watershed feeding the Big Thompson River is better at higher elevations. Snow depth and water content measurements taken in two of the four reporting areas at the end of February by scientists from National Resources Conservation Service are above their 30-year averages. Bear Lake, at 9,500 feet in elevation, topped the list with 14.3 inches of moisture in nearly four feet of snow measured Feb. 26. This is 110 percent of the 30-year average of 13 inches of water content. The 45 inches of snow was 105 percent of the total from the February 2008 reading. Willow Park, at 10,700, was the only other area to exceed the 30-year average for moisture content of the snow, with 14 inches. This is 102 percent of the 30-year average of 13.7 inches of water content in the snow. The average snow depth of 48 inches was only 95 percent of last year’s total.

The other two areas where readings were taken were drastically down from both the 30-year average and the 2008 snow depth. Hidden Valley, at 9,480 feet in elevation, saw the biggest drop off. With just 5.8 inches of moisture in a 24-inch snowpack, the popular recreation area was at 77 percent of the 30-year average and 84 percent of last year’s average snow depth. Deer Ridge, at an even 9,000 feet, with 3.6 inches of water content, was at 82 percent of the 30-year average of 4.4 inches. The average snow depth of 14 inches was only 60 percent of last year’s measurements for the same time frame.

From the Valley Courier (Ruth Heide):

[Colorado Division of Water Resources Acting Division Engineer for Division III Craig Cotten] said the snowpack basin wide for the Rio Grande Basin is 110 percent of average. Some of the highest measurements were logged at the Cumbres Trestle which sits at 135 percent of average and Lily Pond at 111 percent. The Valley mountains were losing snowpack and dipping below average, Cotten added, but moisture in the last couple of weeks brought the snowpack back up.

Cotten said 2008 started out with a really high snowpack, and the Rio Grande was initially forecast to run 960,000 acre feet of water, but the final annual indexed flow was 710,000 acre feet, “still above average but way less than what we were expecting.” The 2008 runoff ended up about the same as 2007 which began with below-average snowpack levels. Cotten said that just shows why it is so difficult to forecast what is going to happen. “We are looking at some other ways to improve that forecasting,” he said. For example, the division may utilize in its forecasting efforts in the future an integrated computer model that uses such data as soil moisture, wind and snowpack…

Cotten said the Natural Resources Conservation Service (NRCS) in its preliminary streamflow forecasts for this year is predicting average flows or a little better depending on the location in the Valley. For example, the March 1 streamflow forecast from NRCS for Costilla Creek is 115 percent of average and San Antonio River at Ortiz is 116 percent of average while the Rio Grande near Del Norte is predicted to be 101 percent of average. The NRCS forecast is for the irrigation months April through September. The March 1 NRCS forecast for the Rio Grande at Del Norte is 535,00 acre feet for April through September. The Division of Water Resources added approximately another 90,000 acre feet for winter flows to develop a preliminary calendar year annual projected flow on the Rio Grande of 630,000 acre feet. Cotten explained that of that annual index, the Rio Grande would owe about 28 percent or 174,00 acre feet to downstream states to meet the Rio Grande Compact. Taking into consideration the amount the river will have to deliver downstream during the irrigation months to meet its estimated compact obligation, Rio Grande water users will likely be curtailed by 14.5 percent, at least initially, Cotten said. He said that would be less curtailment on water users than last year but added, “We have to wait and see what the April 1 forecast brings.” He said the April 1 forecast will provide an even firmer number for the projected annual index…

On the Conejos River system that incorporates the Conejos, Los Pinos and San Antonio Rivers, the current forecast for the year is 355,000 acre feet with 43 percent or 151,100 acre feet obligated to flow downstream to meet Rio Grande Compact obligations according to Cotten. Based on those projections, he said, Conejos water users may see initial curtailments of about 33 percent to make sure the Conejos system delivers its compact obligation. Last year the initial curtailments on Conejos water users were more than 50 percent, Cotten added.

Leave a Reply