B120UP.200702 (04/02/07 1620)
DEPARTMENT OF WATER RESOURCES
California Cooperative Snow Surveys
WATER SUPPLY FORECAST UPDATE
2007 April-July Unimpaired Runoff (1,000 Acre-feet)
Feb 1 %Avg Feb 13 %Avg Feb 20 %Avg Feb 25 %Avg
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Shasta Lake, total inflow Average 1819
90% Exceedence 870 48% 910 50% 900 49% 990 54%
50% Exceedence 1430 79% 1450 80% 1430 79% 1510 83%
10% Exceedence 2330 128% 2310 127% 2270 125% 2330 128%
Feather River at Oroville 1782
90% Exceedence 400 22% 480 27% 470 26% 560 31%
50% Exceedence 800 45% 850 48% 820 46% 910 51%
10% Exceedence 1730 97% 1700 95% 1660 93% 1730 97%
Yuba River near Smartville 1006
90% Exceedence 300 30% 330 33% 310 31% 360 36%
50% Exceedence 550 55% 570 57% 550 55% 600 60%
10% Exceedence 1140 113% 1100 109% 1070 106% 1110 110%
American River, below Folsom Lake 1240
90% Exceedence 310 25% 340 27% 320 26% 410 33%
50% Exceedence 660 53% 670 54% 630 51% 710 57%
10% Exceedence 1290 104% 1260 102% 1200 97% 1260 102%
Mokelumne River, inflow to Pardee Reservoir 461
90% Exceedence 130 28% 150 33% 140 30% 160 35%
50% Exceedence 270 59% 280 61% 260 56% 270 59%
10% Exceedence 540 117% 520 113% 490 106% 480 104%
Stanislaus River, below Goodwin Res. (blw New Melones) 702
90% Exceedence 150 21% 160 23% 150 21% 170 24%
50% Exceedence 380 54% 380 54% 360 51% 370 53%
10% Exceedence 790 113% 770 110% 710 101% 700 100%
Tuolumne River, below La Grange Res. (blw Don Pedro) 1220
90% Exceedence 380 31% 410 34% 390 32% 440 36%
50% Exceedence 730 60% 750 61% 710 58% 750 61%
10% Exceedence 1330 109% 1310 107% 1240 102% 1260 103%
Merced River, below Merced Falls (below Lake McClure) 632
90% Exceedence 170 27% 190 30% 180 28% 210 33%
50% Exceedence 360 57% 360 57% 340 54% 360 57%
10% Exceedence 710 112% 690 109% 660 104% 670 106%
San Joaquin River, below Millerton Lake 1254
90% Exceedence 330 26% 350 28% 340 27% 360 29%
50% Exceedence 730 58% 720 57% 680 54% 690 55%
10% Exceedence 1380 110% 1330 106% 1240 99% 1220 97%
Kings River, below Pine Flat Reservoir 1224
90% Exceedence 300 25% 340 28% 320 26% 340 28%
50% Exceedence 690 56% 680 56% 640 52% 640 52%
10% Exceedence 1290 105% 1240 101% 1160 95% 1130 92%
Kaweah River, below Terminus Reservoir 286
90% Exceedence 70 24% 75 26% 70 24% 80 28%
50% Exceedence 140 49% 130 45% 120 42% 120 42%
10% Exceedence 325 113% 310 108% 285 100% 270 94%
Tule River, below Lake Success 64
90% Exceedence 10 16% 12 19% 11 17% 14 22%
50% Exceedence 30 47% 26 41% 24 38% 25 39%
10% Exceedence 90 142% 82 129% 71 112% 69 109%
Kern River, inflow to Isabella Lake 461
90% Exceedence 100 22% 115 25% 110 24% 115 25%
50% Exceedence 220 48% 210 46% 200 43% 190 41%
10% Exceedence 580 126% 540 117% 490 106% 460 100%
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 1956 to 2005.
