B120UP.200604 (04/27/06 1545)
DEPARTMENT OF WATER RESOURCES
California Cooperative Snow Surveys
WATER SUPPLY FORECAST UPDATE
2006 April-July Unimpaired Runoff (1,000 Acre-feet)
Apr 1 %Avg Apr 11 %Avg Apr 18 %Avg Apr 25 %Avg
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Shasta Lake, total inflow average = 1849
90% Exceedence 2110 114% 2830 153% 3360 182% 3310 179%
50% Exceedence 2510 136% 3150 170% 3650 197% 3560 193%
10% Exceedence 3160 171% 3680 199% 4100 222% 3930 213%
Feather River at Oroville average = 1870
90% Exceedence 1940 104% 2540 136% 3110 166% 3140 168%
50% Exceedence 2300 123% 2840 152% 3390 181% 3390 181%
10% Exceedence 2980 159% 3410 182% 3870 207% 3770 202%
Yuba River near Smartville average = 1044
90% Exceedence 990 95% 1430 137% 1760 169% 1780 170%
50% Exceedence 1230 118% 1600 153% 1910 183% 1920 184%
10% Exceedence 1640 157% 1900 182% 2150 206% 2110 202%
American River, below Folsom Lake average = 1282
90% Exceedence 1400 109% 1930 151% 2340 182% 2310 180%
50% Exceedence 1630 127% 2120 165% 2510 196% 2460 192%
10% Exceedence 2100 164% 2500 195% 2820 220% 2700 211%
Mokelumne River, inflow to Pardee Reservoir average = 469
90% Exceedence 550 117% 720 153% 760 162% 750 160%
50% Exceedence 610 130% 770 164% 810 173% 800 171%
10% Exceedence 750 160% 880 188% 910 194% 890 190%
Stanislaus River, below Goodwin Res. (blw New Melones) average = 716
90% Exceedence 860 120% 1140 159% 1280 179% 1260 176%
50% Exceedence 970 136% 1240 173% 1360 190% 1340 187%
10% Exceedence 1180 165% 1420 198% 1520 212% 1470 205%
Tuolumne River, below La Grange Res. (blw Don Pedro) average = 1230
90% Exceedence 1460 119% 1930 157% 2080 169% 2070 168%
50% Exceedence 1610 131% 2070 168% 2210 180% 2180 177%
10% Exceedence 1890 154% 2320 189% 2420 197% 2360 192%
Merced River, below Merced Falls (below Lake McClure) average = 633
90% Exceedence 760 120% 1050 166% 1130 178% 1120 177%
50% Exceedence 830 131% 1110 175% 1180 186% 1170 185%
10% Exceedence 1010 159% 1260 199% 1310 207% 1270 201%
San Joaquin River, below Millerton Lake average = 1262
90% Exceedence 1530 121% 1960 155% 2050 162% 2070 164%
50% Exceedence 1700 135% 2110 167% 2190 174% 2190 174%
10% Exceedence 1950 155% 2320 184% 2370 188% 2340 185%
Kings River, below Pine Flat Reservoir average = 1234
90% Exceedence 1510 122% 1890 153% 1990 161% 2000 162%
50% Exceedence 1690 137% 2030 164% 2120 172% 2120 172%
10% Exceedence 1890 153% 2210 179% 2280 185% 2250 182%
Kaweah River, below Terminus Reservoir average = 290
90% Exceedence 325 112% 410 142% 445 154% 445 154%
50% Exceedence 360 124% 440 152% 470 162% 470 162%
10% Exceedence 440 152% 510 176% 530 183% 515 178%
Tule River, below Lake Success average = 65
90% Exceedence 61 94% 92 142% 104 160% 104 160%
50% Exceedence 70 108% 100 154% 110 170% 110 170%
10% Exceedence 95 146% 120 185% 129 199% 127 196%
Kern River, inflow to Isabella Lake average = 470
90% Exceedence 520 111% 610 130% 670 143% 680 145%
50% Exceedence 550 117% 660 141% 710 151% 720 153%
10% Exceedence 670 143% 750 160% 790 168% 780 166%
Questions regarding this forecast:
Steve Nemeth: (916) 574-2634 (e-mail nemeth@water.ca.gov)
John King: (916) 574-2637 (e-mail kingjj@water.ca.gov)
Dave Rizzardo: (916) 574-2617 (e-mail daver@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.
