B120UP.200504 (04/28/05 1523)
DEPARTMENT OF WATER RESOURCES
California Cooperative Snow Surveys
WATER SUPPLY FORECAST UPDATE
2005 April-July Unimpaired Runoff (1,000 Acre-feet)
Apr 1 %Avg Apr 12 %Avg Apr 19 %Avg Apr 26 %Avg
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Shasta Lake, total inflow average = 1849
90% Exceedence 1260 68% 1420 77% 1420 77% 1450 78%
50% Exceedence 1620 88% 1740 94% 1700 92% 1700 92%
10% Exceedence 2260 122% 2230 121% 2140 116% 2060 111%
Feather River at Oroville average = 1870
90% Exceedence 1370 73% 1490 80% 1490 80% 1520 81%
50% Exceedence 1710 91% 1790 96% 1760 94% 1760 94%
10% Exceedence 2410 129% 2350 126% 2220 119% 2130 114%
Yuba River near Smartville average = 1044
90% Exceedence 900 86% 970 93% 960 92% 960 92%
50% Exceedence 1100 105% 1120 107% 1100 105% 1090 104%
10% Exceedence 1470 141% 1430 137% 1340 128% 1270 122%
American River, below Folsom Lake average = 1282
90% Exceedence 1300 101% 1390 108% 1370 107% 1370 107%
50% Exceedence 1510 118% 1570 122% 1540 120% 1520 119%
10% Exceedence 1970 154% 1940 151% 1840 143% 1750 136%
Mokelumne River, inflow to Pardee Reservoir average = 469
90% Exceedence 520 111% 570 122% 570 122% 565 120%
50% Exceedence 610 130% 630 134% 620 132% 610 130%
10% Exceedence 740 158% 740 158% 720 153% 700 149%
Stanislaus River, below Goodwin Res. (blw New Melones) average = 716
90% Exceedence 830 116% 900 126% 900 126% 895 125%
50% Exceedence 980 137% 1010 141% 990 138% 980 137%
10% Exceedence 1160 162% 1160 162% 1120 156% 1080 151%
Tuolumne River, below La Grange Res. (blw Don Pedro) average = 1230
90% Exceedence 1620 132% 1700 138% 1680 137% 1670 136%
50% Exceedence 1770 144% 1820 148% 1790 146% 1770 144%
10% Exceedence 2050 167% 2050 167% 2000 163% 1950 159%
Merced River, below Merced Falls (below Lake McClure) average = 633
90% Exceedence 830 131% 910 144% 910 144% 910 144%
50% Exceedence 980 155% 1000 158% 990 156% 980 155%
10% Exceedence 1120 177% 1120 177% 1100 174% 1070 169%
San Joaquin River, below Millerton Lake average = 1262
90% Exceedence 1670 132% 1730 137% 1710 136% 1700 135%
50% Exceedence 1840 146% 1870 148% 1840 146% 1820 144%
10% Exceedence 2090 166% 2080 165% 2020 160% 1970 156%
Kings River, below Pine Flat Reservoir average = 1234
90% Exceedence 1560 126% 1630 132% 1620 131% 1600 130%
50% Exceedence 1720 139% 1770 143% 1740 141% 1710 139%
10% Exceedence 1940 157% 1940 157% 1890 153% 1830 148%
Kaweah River, below Terminus Reservoir average = 290
90% Exceedence 365 126% 370 128% 365 126% 365 126%
50% Exceedence 390 135% 395 136% 390 135% 385 133%
10% Exceedence 470 162% 465 161% 445 154% 430 148%
Tule River, below Lake Success average = 65
90% Exceedence 70 108% 72 111% 73 113% 70 108%
50% Exceedence 80 123% 80 123% 80 123% 75 116%
10% Exceedence 110 170% 105 162% 100 154% 91 140%
Kern River, inflow to Isabella Lake average = 470
90% Exceedence 570 121% 610 130% 630 134% 625 133%
50% Exceedence 640 136% 670 143% 680 145% 675 144%
10% Exceedence 760 162% 760 162% 750 160% 720 153%
Questions regarding this forecast:
Call (916) 574-2617 (e-mail daver@water.ca.gov)
or (916) 574-2634 (e-mail nemeth@water.ca.gov)
or (916) 574-2637 (e-mail kingjj@water.ca.gov)
Runoff forecasts are unimpaired (full natural) flows which represent the
natural water production of the river basin, unaltered by upstream diversions,
storage, or export or import of water to or from other watersheds.
The median (50%) forecast assumes median conditions after the date of forecast.
Runoff exceedence levels are derived from historical data.
The 90 percent exceedence level and the 10 percent exceedence level together
comprise a range about the median forecast in which the actual runoff should
fall 8 times out of 10.
Forecasts are stated in 1,000's of acre-feet and percent of (50-year) average.
The averages are for the period 1951 to 2000.
