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01'\.',,<1 ...... rJ-u~ J-t localized operational requirements at each reservoir, In general, if 1991 nonnal runoff is evenly distributed over the project reservoirs, full water deliveries can be supported and some refill of carryover storage can be provided, For this reason, only normal or drier water supply scenarios currently are being analyzed in detail. Preliminary operations forecasts have been performed for water year 1991 using three water supply scenarios: "median," "dry," and "criticaL" These projections demonstrate that there is a significant risk of continuing severe drought conditions and water supply deficiencies in 1991. Depending on the severity of conditions, which at this time can only be cast in terms of historical water supply probabilities, operation of the Central Valley Project in water year 1991 could stretch project capabilities to their limits. The September 30, 1990, storage in Central Valley Project reservoirs was 3.98 million acre-feet. The projected September 3D, 1991 storage for each of the three water supply scenarios is 5.6 (median), 4,0 (dry), and 3,2 (critical) million acre-feet. The Newlands Project and certain other areas in the Lahontan basin should not have shortages in 1991, if the runoff of the Truckee and Carson Rivers is at least 100 percent of normal. The runoff of the Humboldt River will need to be at least 120 percent of normal in 1991 in order to avoid shortages on the Humboldt Project. LOWER COLORADO REGION The Lower Colorado Region includes most of Arizona and portions of California, Nevada, Utah, and New Mexico, The region encompasses the portion of the Colorado River drainage basin below Lees Ferry, Arizona (near Page, Arizona), Water Year 1990 Soil moisture measurements indicated predominantly moderate to severely dry conditions at the beginning of the 1990 water year for most of the region, Conditions improved and degraded, variously, as the water year progressed, Due to late season precipitation, conditions improved substantially in most of Arizona and southern Nevada by year's end, resulting in moist to very moist conditions, However, indices for northwestern Arizona and southern California still showed extreme drought conditions. Overall, soil moisture content was much improved in the region at the beginning of water year 1991 compared to conditions at the beginning of the previous water year, Snowpack conditions in the river basins originating in Arizona and western New Mexico were well below normal throughout the snow pack accumulation season, Snowpack was less than 50 percent of normal in all of the basins by May 1, 1990, 7