B120UP.200703 (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)
Mar 1 %Avg Mar 13 %Avg Mar 20 %Avg Mar 27 %Avg
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Shasta Lake, total inflow average = 1819
90% Exceedence 1040 57% 950 52% 880 48% 890 49%
50% Exceedence 1550 85% 1410 78% 1310 72% 1270 70%
10% Exceedence 2350 129% 2150 118% 2020 111% 1950 107%
Feather River at Oroville average = 1782
90% Exceedence 740 42% 690 39% 600 34% 610 34%
50% Exceedence 1090 61% 960 54% 860 48% 840 47%
10% Exceedence 1900 107% 1670 94% 1540 86% 1470 83%
Yuba River near Smartville average = 1006
90% Exceedence 440 44% 410 41% 360 36% 370 37%
50% Exceedence 680 68% 620 62% 560 56% 530 53%
10% Exceedence 1180 117% 1010 100% 920 91% 870 87%
American River, below Folsom Lake average = 1240
90% Exceedence 540 44% 510 41% 450 36% 460 37%
50% Exceedence 850 69% 770 62% 670 54% 640 52%
10% Exceedence 1390 112% 1250 101% 1110 90% 1040 84%
Mokelumne River, inflow to Pardee Reservoir average = 461
90% Exceedence 210 46% 200 43% 170 37% 180 39%
50% Exceedence 330 72% 310 67% 270 59% 260 56%
10% Exceedence 550 119% 470 102% 410 89% 380 82%
Stanislaus River, below Goodwin Res. (blw New Melones) average = 702
90% Exceedence 290 41% 280 40% 240 34% 250 36%
50% Exceedence 480 68% 440 63% 390 56% 370 53%
10% Exceedence 780 111% 700 100% 620 88% 590 84%
Tuolumne River, below La Grange Res. (blw Don Pedro) average = 1220
90% Exceedence 550 45% 520 43% 450 37% 460 38%
50% Exceedence 850 70% 770 63% 680 56% 660 54%
10% Exceedence 1320 108% 1180 97% 1050 86% 990 81%
Merced River, below Merced Falls (below Lake McClure) average = 632
90% Exceedence 250 40% 230 36% 200 32% 210 33%
50% Exceedence 390 62% 350 55% 300 47% 280 44%
10% Exceedence 690 109% 610 97% 520 82% 480 76%
San Joaquin River, below Millerton Lake average = 1254
90% Exceedence 460 37% 430 34% 380 30% 390 31%
50% Exceedence 770 61% 690 55% 590 47% 560 45%
10% Exceedence 1280 102% 1100 88% 960 77% 880 70%
Kings River, below Pine Flat Reservoir average = 1224
90% Exceedence 420 34% 400 33% 360 29% 370 30%
50% Exceedence 720 59% 660 54% 570 47% 550 45%
10% Exceedence 1190 97% 1040 85% 920 75% 850 69%
Kaweah River, below Terminus Reservoir average = 286
90% Exceedence 110 38% 100 35% 85 30% 90 31%
50% Exceedence 155 54% 140 49% 120 42% 120 42%
10% Exceedence 295 103% 250 87% 210 73% 200 70%
Tule River, below Lake Success average = 64
90% Exceedence 18 28% 16 25% 13 20% 15 24%
50% Exceedence 31 49% 28 44% 24 38% 24 38%
10% Exceedence 74 116% 61 96% 50 79% 47 74%
Kern River, inflow to Isabella Lake average = 461
90% Exceedence 135 29% 125 27% 100 22% 115 25%
50% Exceedence 210 46% 190 41% 160 35% 170 37%
10% Exceedence 460 100% 380 82% 310 67% 290 63%
Questions regarding this forecast:
John King: (916) 574-2637 (e-mail kingjj@water.ca.gov)
Steve Nemeth: (916) 574-2634 (e-mail nemeth@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.