Following March, one of the driest months in Colorado history, much of the state received above average precipitation in April, alleviating some drought restrictions and leading some individuals and communities to ponder a potential end to the state’s multi-year drought. However, even with recent May storms, climate experts at Colorado State University stress that the state is far from recovering from drought conditions.
"Some individuals and community leaders may be under the impression that the state is in a good position in relation to drought because of the wet weather Colorado has received in April and May," said State Climatologist Roger Pielke. "However, overall precipitation is still behind average and snowpack levels are low and quickly depleting. To help ensure Colorado has the water resources to get through the long drought season, municipal and individual efforts at water use efficiency remain very important throughout the state."
According to Pielke, who directs Colorado State’s Colorado Climate Center, it is quite unlikely, even with last week’s rain and snow, that much of Colorado will recover from drought in 2004. The state is in its seventh year of drought conditions, and statewide recovery, like the drought itself, will likely be a multi-year process.
"Colorado is past the period of significant snow accumulation in the mountains, so much of the water supply for this summer is already known. The state’s drought will continue, but what happens throughout the remainder of May, traditionally a wet month for large parts of Colorado, will influence how severe the drought impacts will be this summer," Pielke said. "We could make up some of our deficit and reduce demand, or fall much further behind average depending on the weather."
Pielke added that Colorado would need unprecedented, almost unrealistic widespread amounts of rain to see a complete statewide recovery. "Since the state is in a multi-year period with below average precipitation, communities need to continue to be efficient in water use, a policy that should always be applied in this semi-arid state," he said.
Warm weather during the first half of May already has resulted in early runoff and evaporation of some of the increased snowpack generated from April storms. On May 1, on a statewide basis, Colorado’s snowpack had been boosted to 68 percent of average for the date (last year was 87 percent of average at this time) and 78 percent of last year. By May 17, even with last week’s storms, the snowpack had already melted to 43 percent of average and 51 percent of last year, according to the USDA’s Natural Resources Conservation Service, or NRCS.
The snowpack in the South Platte River Basin, where Denver gets its water, dropped from 65 percent of average on May 1 to 52 percent on May 17. In the Arkansas River basin, where several other Front Range cities draw their water, the snowpack has since dropped to 58 percent of average. The Colorado River Basin, which feeds states throughout the West, has been reduced to 37 percent of average.
"Snowpack levels are important in Colorado because snowpack provides much of the water in the state’s rivers, streams and reservoirs. Eight major Colorado river systems also provide water to 10 western states," Pielke said. "If Colorado does not receive additional significant summer rains and these snowpack levels continue to decrease at a rapid rate, the state could be facing serious late summer drought conditions, including a heightened fire risk. State policy makers should plan now for consequences to the state’s water needs if these very serious drought conditions actually occur."
Individual Colorado basin totals as of May 17 as reported by the NCRS follow.
– Yampa and White Basin – 36 percent of average, 36 percent of last year’s snowpack.
– Colorado Basin – 37 percent of average, 32 percent of last year’s snowpack.
– Gunnison Basin – 56 percent of average, 71 percent of last year’s snowpack
– San Juan, Animas, Dolores and San Miguel basins – 60 percent of average, 155 percent of last year’s snowpack.
– Rio Grande Basin – 48 percent of average, 164 percent of last year’s snowpack.
– Arkansas Basin – 58 percent of average, 69 percent of last year’s snowpack.
– South Platte Basin – 52 percent of average, 45 percent of last year’s snowpack.
Reservoir storage totals as reported by the NRCS vary throughout the state but overall are below average – yet well above where they were this time last year. In early May, statewide reservoir storage was 84 percent of average and 139 percent of last year.
Broken down by individual basin, reservoir storage totals follow.
– Yampa and White Basin – 97 percent of average, 83 percent of last year.
– Colorado Basin – 89 percent of average, 211 percent of last year.
– Gunnison Basin – 111 percent of average, 135 percent of last year.
– San Juan, Animas, Dolores and San Miguel basins – 85 percent of average, 130 percent of last year.
– Rio Grande Basin – 54 percent of average, 91 percent of last year.
– Arkansas Basin – 53 percent of average, 120 percent of last year.
– South Platte Basin – 81 percent of average, 128 percent of last year.