WSP12938 - Laserfiche WebLink

Home Browse Search

Precipitation Accompanying the warm temperatures during March, was a dry weather pattern which will have lasting impacts for Colorado's water users. Monthly precipitation totals at Colorado SNOTEL sites was a disappointing 81 % of average. Basinwide percentages ranged from only 69% of average in the South Platte Basin, to 92% of average in the Rio Grande Basin. For the first half of the 2004 water year, which began on October 1, 2003, the state's precipitation totals remain at only 87% of average. Most of the state's major river basins are reporting below average water year totals as well. The South Platte Basin is reporting the lowest percentage at only 61 % of average. Only the Rio Grande and combined San Juan, Animas, Dolores, and San Miguel basins can boast of having an above average water year total at this time. Reservoir Storage Reservoir storage across Colorado saw slight improvements during March. The greatest improvements were seen in the Gunnison Basin, which improved by more than 43,000 acre- feet during the month. These improvements were enough to boost storage in the Gunnison basin to 105% of average. This is the highest percent of average storage in the state, and the highest in this basin since May, 2002. Statewide, storage improved during March by slightly more than 110,000 acre-feet. During March, the average statewide storage actually decreases slightly. This has yielded an increase in the statewide storage from 78% of average on March 1, to 81 % of average on April 1. Basinwide storage is below average in all of the major basins of the state. The Arkansas Basin is reporting the greatest deficit storage, with current volumes at 274,000 acre-feet below the average for April 1. As a rule, this year's April 1 storage is tracking above last year's across the state. All basins, with the only exception of the Rio Grande, are reporting volumes greater than those oflast year at this time. Streamflow A warm and dry March has had a dramatic impact on the state's water supply picture for 2004. Sharp decreases in expected runoff volumes have occurred statewide this month. Even in those basins, which just a month ago were forecast at near to slightly above average, can now expect well below normal volumes this year. Most forecasts across western Colorado have dipped to 50% to 70% of average for the 2004 runoff season. Across the Rio Grande and San Juan Basins, which have'had the best runoff prospects throughout this season, can now only expect volumes of 70~ to 85% percent of average. Some of the lowest forecasts in the state continue along the Front Range.tributaries of the South Platte River, where less than 50% of average volumes are forecast in several basins. While it remains possible to see improvements in snowpack and runoff during April and May, its impact is almost certain to be minimal at this point in the water year.