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SAN JUAN/DOLORES BASIN Basinwide Conditions Assessment The SWSI value for the month was 3.9. The Natural Resources Conservation Service reports that March 1 snowpack is 1550/0 of normal. Estimated average daily flows at the Animas River at Durango were 230 cfs. The estimated average daily flows for Dolores River at Dolores were 82 cfs. The average daily flows at the La Plata River at Hesperus were 5.1 cfs. Durango recorded 2.72 inches precipitation for the month which is well above the 30-year average of 1.72 inches (1590/0 of normal). Precipitation in for the month was the 14th highest amount within the last 112 years of record. Precipitation to date in Durango, for the water year, is 13.25 inches which is 1600/0 of the historic average. Temperatures in February were below normal for the month. Durango was 3.20 below its 30-year average high and 1.80 below its 30- year average low. At the end of the month Vallecito Reservoir contained 64,688 acre-feet compared to its normal contents of 54,040 acre-feet (1200/0 of normal). McPhee Reservoir has 286,542 acre-feet compared to its normal contents of 257,514 acre-feet (1110/0 of normal). Lemon Reservoir has 22,660 acre-feet as compared to its normal content of 19,849 acre-feet (1140/0 of normal) Outlook Not as much snow and warmer temperatures at the end of February. Many major storm systems have hit the southwest part of Colorado this year and colder than normal temperatures have not had much impact on melting snow left by the storms. To date the total snow-water-equivalent within the basin has exceeded the average snow-water-equivalent for the year with the average peak date occurring in April. The NRCS data on February 29, 2008 reported a snow- water-equivalent of 1580/0 of average. The Pine River Water Conservancy District began releasing water out of Vallecito Reservoir to ensure there is enough available space to hold back the spring runoff. Administrative/Manaqement Concerns The compact period on the La Plata between Colorado and New Mexico began on February 15th, but remained off compact call for the month. The compact requires that half the flow and the upper index gage (at Hesperus) must be delivered across the Stateline the following day. The low level snow melting in the La Plata River basin has kept the flow at the Stateline well above the flows at Hesperus. I- W S W ::J ....J <C > 0 >< w o z - -1 >- 0:: o 200,000 180,000 ~ 160,000 LL ~ 140,000 <( s~ 120,000 o Li 100,000 w ~ 80,000 <( 5 60,000 ~ B 40,000 300,000 Q3 ~ ~ 250,000 co ai ~ 200,000 o U5 ~ 150,000 ~ :J 100,000 9 Mar-08 SAN JUAN-OOLORES BASIN SNSI HISTORY -2 -3 -4 Jan-99 Jan-OO Jan-01 Jan-02 Jan-03 Jan-04 Jan-05 Jan-OO Jan-07 Jan-08 MJNTH / YEAR ANlrvlAS RIVER NR. DURANGO, FLOW BY WATER YEAR 20,000 o O:i Nov Dee Jan Feb rvlarch -----8-- WET (1973) ~ DRY (2002) ---fr-- AVG -*2008 REPRESENTATIVE RESERVOI RS 400,000 350,000 50,000 l\t1cPhee Vallecito Lerron III Avg.2128 Contents I!JJ 2129/08 Contents