Colorado State Basin Outlook Report

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State Basin Outlook Reports monthly December average. For most of the state, December's precipitation more than made up for the November deficit, and water year totals for the October - December period range from 96% of average in the South Platte basin to 132% of average in the Rio Grande basin. Statewide, water year totals are 112% of average and are 99% of last year's water year totals on this date. RESERVOIR Colorado's reservoir storage finally returned to above average volumes during the summer of 2007, with levels not reached since 2001. While storage has declined from late summer demands since that time, storage remains near average across most of the state as of January 1. Volumes currently range from 83% of average in the South Platte basin to 110% of average in the San Juan, Animas, Dolores and San Miguel basins. For the state, volumes are now standing at 98% of the long- term average. These volumes are slightly ahead of last year's storage on this date, at 105% of those levels. Only two basins, the Gunnison and the combined San Juan, Animas, Dolores and San Miguel, have been consistently tracking at above average volumes thus far during the 2008 water year. Although improving slightly each month since October, the South Platte basin continues to report the lowest percent of average storage in the state. . STREAMFLOW Runoff forecasts look promising for 2008 for most of the state. As expected, the best prospects for above average runoff volumes occur across the southern basins. The Rio Grande headwaters and the San Juan River can expect volumes above 130% of average. Above average volumes are also forecast throughout the Gunnison and Arkansas basins, along with the San Miguel, Dolores, Animas, and a few upper reaches of the Colorado River. The lowest forecasts, as a percent of average, occur throughout the South Platte and North Platte basins. While below average, most locations in these basins range from 85% to 90% of average. Slightly higher percentages are forecast in the lower reaches of the Colorado River, along with the Yampa and White basins, which range from 90$ to 100% of average at most forecast points. There remains ample time in the 2008 winter season to improve upon the current conditions in these dryer areas of the state. Water managers will need to closely monitor weather patterns in these basins since they are the most vulnerable to future conditions. GUNNISON RIVER BASIN as of January 1, 2008 Snowpacks in the Gunnison River Basin got off to a relatively slow start to begin the 2008 Water Year. By the end of October 2007, snowpacks were only 55 percent of average. An extremely dry November brought the snowpack figures down to 28 percent of average by November 30. Fortunately, things completely turned around during December. Snow accumulation during December, based on SNOTEL data, was 209 percent of average, bringing the January 1 snowpacks in the basin to 117 percent of average. Along with 2005, this is the highest January 1 figure since 1997. Watersheds within the basin ranged from 109 percent of average in the Surface Creek area to 121 percent of average in the Uncompahgre Drainage. Mountain precipitatiion was near normal during October (103 percent of average). During November, precipitation totals were only one half of the average. However, nearly twice normal precipitation during December brought year-to-date precipitation totals up from 74 percent of average at the end of November to 118 percent of average at the end of December. Reservoir storage is slightly below the levels reported last year but is still above normal at 106 percent of average. Spring and summer streamflows are expected to be near to above normal throughout the basin. Runoff volumes are forecast to range from 103 percent of average for the Slate River near Crested Butte to 117 percent of average for Tomichi Page2of15 http://www.wcc.nres.usda.gov/cgibin/bor2.p1?state=co&year=2008&month=l&format=text 4/14/2008