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<br />3~n! M <br /> <br />MID-PACIFIC REGION <br /> <br />The Mid-Pacific Region includes most of California and portions of Nevada and <br />Oregon, Projects include the Central Valley Project in California and other <br />smaller projects on streams originating in the Sierra Nevada, lower Cascade, and <br />southern California mountain ranges, <br /> <br />Water Year 1990 <br /> <br />Water year 1990 began with indications of a possible end to the 3-year drought in <br />California with the occurrence of strong storms in late September and October of <br />1989, The Central Valley Project had averted water shortages over most of the <br />project in 1989 by virtue of an extraordinarily wet March. It appeared that there <br />was a high probability for full water deliveries in 1990. Unfortunately, the <br />outlook then began to worsen steadily, <br /> <br />The 6-month period November 1989 through April 1990 (the normal rainy season <br />in California) produced only a few moderate rain storms interspersed with <br />prolonged periods of dry weather, In February, Central Valley Project water <br />contractors and water rights holders served by the project were informed of <br />impending deficiencies in their water supplies during 1990, Most contractors were <br />cut to 50 percent supplies and water rights entities were cut to 75 percent of full <br />supply, By May 1, 1990, conservative forecasts showed Central Valley Project <br />storage dropping to 2,9 million acre-feet in order to support even the deficient <br />water deliveries earlier committed to by Reclamation, <br /> <br />Then came the "miracle May" of 1990, Two series of storms, the seconcl (and <br />larger) over Memorial Day weekend, produced by far the greatest reservoir inflows <br />of the entire water year, These storms resulted in the wettest May of record at <br />many locations in California, including Shasta and Trinity Dams, <br /> <br />Inflow from the May storms dramatically modified the water supply forecasts at a <br />time of year when they are usually already accurately established, Reclamation <br />restored all water rights entities to 100 percent supplies, as required by their <br />agreements, The Central Valley Project also made an additional 83,000 acre-feet <br />of water available to wildlife refuges, However, with only about 50 percent of <br />desirable carryover storage, the project is again at risk of deficiencies in 1991. <br /> <br />The four water years 1987, 1988, 1989, and 1990 constitute one of California's <br />most severe droughts of this century, Under California's Sacramento River Index, <br />water year 1989 was classified a "below normal" year; the other three water years <br />1987, 1988, and 1990 were "critical" years, <br /> <br />Natural runoff during the 4-year period 1987-1990 is the lowest for this century in <br />the California River basins above New Melones, Friant, and Folsom Dams, <br />Central Valley Project-wide, only the droughts of 1928-34 and 1976-77 are even <br /> <br />5 <br />