Click on the thumbnail graphics for the latest U.S. Drought Monitor map along with the September 20, 2011 and October 12, 2010 maps for some insight into the progression of the current drought.
From the Grand Junction Free Press (Hannah Holm):
Next year’s outlook is uncertain, and water managers are being conservative about putting further pressure on reservoirs. The Uncompahgre Valley Water Users Association decided to cut off water deliveries two weeks early to keep more water in storage for the 2013 growing season.
Reservoir storage levels around the state are low, and more extreme conservation measures are likely next year if winter storms fail to significantly refill them. Grand Valley domestic water providers have warned that another dry winter could lead to mandatory restrictions and higher water rates. According to the Natural Resource Conservation Service, reservoir storage levels at the end of August for some of the state’s major river basins were as follows:
• Colorado River Basin: 64% of average, and 63% of capacity. At the same time in 2011, the basin’s storage levels were at 111% of average.
• Gunnison River Basin: 63% of average, and 52% of capacity. At the same time in 2011, the basin’s storage levels were at 108% of average.
• South Platte River Basin (includes Denver and the northern Front Range): 71% of average, and 44% of capacity. At the same time in 2011, the basin’s storage levels were at a whopping 121% of average.
• Arkansas River Basin (includes Colorado Springs and Pueblo): 63% of average, and 19% of capacity. At the same time in 2011, this basin was already beginning to experience drought, and had storage levels at 85% of average.
Drought conditions and reservoir storage levels on Front Range matter to Western Slope water users, and vice versa, because of the extent to which Front Range water users rely on trans-mountain diversions. On average, about 500,000 acre-feet per year flows from Western Slope headwaters streams (mostly in the Colorado Basin) into the South Platte and Arkansas River Basins to irrigate crops and provide water to cities. An acre-foot is about enough to supply 2-3 households’ domestic water needs for a year.