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RIO GRANDE BASIN Basinwide Conditions Assessment The SWSI value of -0.9 indicates that for March the basin water supplies were below normal. The Natural Resources Conservation Service reports that April 1 snowpack is 77% of normal Flow at the gaging station Rio Grande near Del Norte averaged 362 cfs (134% of normal). The Conejos River near Mogote had a mean flow of 163 cfs (207% of normal)_ Flow at the slate line was 162% of normal. Storage in Platoro, Rio Grande. and Santa Maria reservoirs totaled 61% of normal as of the end of March. Throughout the upper Rio Grande basin, streamflow during March was well above normal due to the abnormally high temperatures. Weather condrtions in the San Luis Valley were much warmer and drier than normal during March. For several days. the maximum daytlOle temperatures reached or exceeded the 7()..degree mane Snowfall on the Valley floor totaled only 1.0 inch. one of the worst snOYJfall months since 1970. Alamosa received a paltry 0.19 inches of precipitation during the month. A recent study of 10 SNOTEL sites in the upper Rio Grande basin showed the existing snowpack began to decline about March 8. over a month before the normal peak of April 15, Outlook Current NRCS streamflow forecasts predict the April through September runoff to be 87% of average on the Rio Grande near Del Norte and 91% of average for the Conejos near Mogote. Other streams in the basin are forecast as low as 76% of normal for Saguache Creek. but most fall in the mid-70 10 low-90 percent of normal range. The below normal reservoir storage levels compound the waler availability problem. Soil moisture condrtions are good in most locations around the basin due to the earty April precipitation. Adrninistrative/ManaQernent Concerns Based on the current forecast, there will be curtailments of water rights on the Rio Grande of approximately 15% and for the Con€Jos River system approximately 25% this irrigation season. Public Use Impacts Diversions from local streams for irrigation purposes began the last week of March_ Apr-04 -- I f j~~ i " rll . , ~ .1 . ~ >1 'I ,I - - - - - - - - - - ~- RO CJW-a .'-Il. caKRIE. FtON BV W. 'EM "IEAA m= ~ ~- ~ I 12'jJcoot- +-- T L l~o::o; -+ . -+- < . I 0 itl!lO,O::Oj- _f... ~ '""=/C:- +-- , , > a",=~ _~ -::' ~ 1 ,L ~ ~ -----' ~ "" ,~ "" ~ ... .... - '<'fil'9lJ1l -~'"'" -,'" -~ ~"lM~ "=, ---.. 200::0.- -I I 1..=. t l ;w=. , ---+ --.~ ~ ~ "'- 5COO'- , ~..... - ''''ll3al~ ':\O'A:Ilec.-.. 5