DWR_4151813 - Laserfiche WebLink

COLORADO WATER SUPPLY CONDITIONS REPORT April 13, 1990 Precipitation is for the month of March. Both high elevation and low elevation precipitation data are included. Reservoir storage and snowpack conditions were measured on April 1, 1990. Conditions as a Percentage of Normal Reservoir Basin Storage Precipitation Snowpack South Platte 101% 316% 102% Arkansas 111% 119% 66% Rio Grande 93% 108% 53% Gunnison 156% 102% 54% Colorado 82% 118% 77% Yampa/White N/A 121% 89% San Juan/Dolores 38% 102% 45% NOTE: Beginning March 1, 1990, reservoir storage for the San Juan Dolores basin was recomputed to not include Navajo Reservoir The Surface Water Supply Index (SWSI) developed by this office is used as an indicator of water supply conditions in the state.. It is based an reservoir storage, streamflow, and precipitation for the summer period (May 1 - December 1) and reservoir storage, snowpack, and precipitation for the winter period (December 1 - May 1) . Weight factors are applied to each of the measured hydrologic components in computing the SWSI values. These computations are based on the probability of non-exceedence of individual components; that is, the probability that a measured value is equal to or less than the historic average. During the winter period, snowpack is the primary component in each basin except the South Platte. The following SWSI values were computed for each of the seven basins on April 1, 1990: • Change from Basin SWSI Value Mar. I, 1990 South Platte -0.5 +1.2 Arkansas -2.3 +0.2 Rio Grande -2.8 +0.4 Gunnison -2.8 +0.1 Colorado -1.9 +0.7 Yampa/White -1.8 0.0 San Juan/Dolores -3.3 +0.2 SCALE -4 -3 -2 -1 0 +1 +2 +3 +4 Severe Moderate Below Near normal Above normal Abundant drought drought normal supply