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COLUMBIA BASIN -- Continued to be 36.1 million acre-feet or 110 percent of normal for the January-September period. Reservoir storage Is excellent. was above normal in all aress and meet summer water supply needs. Storage 8S of April 1 should be adequate [0 GREAT BASIN The \later supply outlook. for the Great Basin Is for much above normal runoff ["angina from 105 percent in the Truckee-Tahoe Basin to over 700 percent for the local inflow on the Lower Sevier River at Gunnison. Most streams are forecsst between 125 to 225 percent of average. The Kumbolt River Bas!n is an area of major concern for the spring runoff season. with predictions near 300 percent of average. Also. high inflows to both Utah Lake and the Great Salt Lake are likely to push these large bodies of water to higher levels than last year, and to levels not previously experienced in almost a century. March precipitation waa generally near normal state wide but the heaviest area was over the Heaver and Sevier Basin in south central Utah where some reports were in excess of 150 percent of normal. Seasonal precipitation, October through March, is generally 120 to 150 percent over most of the state. Extreme southern areas of Utah are less than HU percent of normal but the northwest corner of Utah and the Sevier River drainage have received amounts in excess of 150 percent. Seasonal. October through March. precipitation amounts this year have exceeded previous observations over the last 50 years at such locations as Ogden Pioneer Power House. Farmington USU, Minersvllle. and Kanosh. Snowfall during March was nesr normal over northern Utah, above average in central portions of the state, and below normal over extreme southern areas. Some average baain snowpacks include: Hear River--I27 percent, Logan--119 percent, Ogden--153 percent, Weber--135 percent, Jordan--128 percent, Provo--129 percent, Beaver--146 percent, Upper Sevier--95 percent, and Lower Sevier--172 percent. Some rock and mud slides have slready occurred along the Wasatch front and the threat of additional slides through the snowmelt period is very real. Observed streamflow continues to reflect the saturated aoil conditions and high ground water flow. The seven index station6 measured by the USGS in Utah averaged 146 percent for the month, and since October 1 have averaged 167 percent. The elevation of the Great Salt Lake on April 1 was 4207.35 MSL. a rise of 0.65 feet in the las t month. The lake is expected to rise another 1 to 1.5 feet to a level of 4208.0 to 4209.0 feet HSL early this summer. Utah Lake was 3.40 feet above compromise, a rise of 0.20 feet in the last month and is expected to rise an additional 1.5 to 2.5 feet by late spring. The flood potential for this spring IS snowmelt has changed very little in the last month and continues to look threatening. April through July forecasts indicate runoff volu~s slightly less than those which occurred last year. COLORADO BASIN The water supply outlOOK ranges from below normal in portions of central Arizons to much above normal along the Colorado main stem. The potential for some spring snowmelt flooding. is still high along the east slope of the Wasatch Range in Utah, the Lower Gunniaon Basin, and the San Miguel, and Uncompahgre and Plateau Creek drainages in Colorado. Low lying areas along streams with moderate or higher volumes may also experience SOIDE! runoff problems. Precipitation during March was quite varied ranging from less than 30 percent over IDOst of Arizona, to nearly twice normal at spotty locations in western Colorado. Some average baain precipitation amounts for March include: Green River above Flaadng Gorge--90 percent, Upper Colorado River--135 percent. snd the San Juan 8asin--85 percent. Seasonal precipitation, October through March, ranges from 75 percent of normal over Arizona 'to greater than 150 percent over portions of weatern Colorsd~~. March snowfall was near normal over much of the Upper Colorado. Some average basin anowpacka include: Upper Colorado main stem--141 percent. Gunnison drainage--137 percent, San Jusn 8asin--ll1 percent, Yampa and White Rivera--12Z percent, and the Green River above Flaming Gorge Reservoir--83 percent. April 1 snow surveys revealed that new water content records were established for 21 snow courses. Moat of the new records were in the Gunnison and Colorado River watersheds. Saturated soils, snowmelt, and spring rains may produce aome rock or mud slides on steep slopes. The wet soil and ample ground water conditions are well supported by the continued high flow on the Colorado and Green River drainages since the start of the water year. Reservoir storage remains high with the combined storage of ten major reservoirs above Lake Powell of 5.9 million acre-feet, 74 percent of capscity. 134 percent of average. and about 250.000 acre-feet lower than last year at this time. Storage in Lake Powell is 21.06 million acre-feet. 84 perc.ent of cspacity and about 1.5 million acre-feet lower than last year at this time. The April-July inflow forecast to Lake Powell is 11.5 million acre-feet. 154 percent of the 20-year, 1961 to 1980 average. RIO GRANDE BASIN The predicted water supply outlook varies from IU5 to 156 percent of average in the Colorado portion of the basin and from 95 to 185 percent of norms 1 in New Mexico. Weather conditions during the month of March were very erratic producing variable amounts of precipitation across the basin. The San Luis Valley of Colorado received the greatest amounts which were near 2 to 2.5 times average. The San Juan Mountains area was below normal with amounts as low as 50 percent of average reported. However, some areas of the Sangre De Cristos of northern New Mexico received] times normal. October through March seasonal totals are now near normsl over most of the basin. Snowfall for the month of Msrch was slightly below normal over all but the eastern areas in the Sangre De Cr!stos of southern Colorado and northern New Mexico and isolated areas of the San Juan Mountains along the Colorado-New Mexico border where amounts of up to 3 times normal were observed. Snowpack is now 115 percent of aversge in the basin in Colorado which is slightly higher than last year at this time. In the New Mexico portion of the basin, 130 percent of average is on the ground which is around 10 percent lower than last year at this time. Reservoir storage continues well above normal and is about equal to levels observed at this time last year. ARKANSAS BASIN The water supply outlook for the ArKanaas is for sbo.ve normal runoff ranging from percent of the 20-year (1961-1980) average. River Badn 135 to 165 Total precipitation amounts for the mnth of March were much above normal over most of the basin. The atorm track that was established across the area late in the month of February continued through March producing precipitation amounts of 150 to 200 percent of average over the eastern half of the basin, with amounts nesr three times average being reported. Seasonal precipitation totals, October through March, now range from 70 percent in isolated areas of the northern valley to near normal along the southern tributaries. 2 . . . .continued on page 6