B-120 Water Supply Forecast Summary (posted on 05/07/20 16:31)

Department of Water Resources
California Cooperative Snow Surveys

May 1, 2020 FORECAST
OF UNIMPAIRED RUNOFF

April-July Forecast Summary (in thousands of acre-feet):
HYDROLOGIC REGION
and Watershed
Apr-Jul
Forecast
Percent
of
Average
80%
Probability
Range
NORTH COAST
Trinity River at Lewiston Lake23036%180  -280
Scott River near Fort Jones10460%  
SACRAMENTO RIVER
Sacramento River above Shasta Lake12041%  
McCloud River above Shasta Lake26068%  
Pit River above Shasta Lake68067%  
Total Inflow to Shasta Lake1,05060%860  -1,210
Sacramento River above Bend Bridge1,48061%1,230  -1,750
Feather River at Oroville94055%780  -1,080
Yuba River near Smartsville60062%480  -710
American River below Folsom Lake79066%650  -950
SAN JOAQUIN RIVER
Cosumnes River at Michigan Bar9576%80  -130
Mokelumne River Inflow to Pardee29063%240  -350
Stanislaus River, below Goodwin Res.41060%340  -500
Tuolumne River below La Grange63053%560  -720
Merced River below Merced Falls29047%240  -340
San Joaquin River inflow to Millerton Lk65053%530  -760
TULARE LAKE
Kings River below Pine Flat Res.64053%510  -760
Kaweah River below Terminus Res.14551%120  -165
Tule River below Lake Success2844%21  -36
Kern River inflow to Lake Isabella24052%200  -280
NORTH LAHONTAN
Truckee River, Lake Tahoe to Farad accretions15562%  
Lake Tahoe Rise, in feet0.860%  
West Carson River at Woodfords3669%  
East Carson River near Gardnerville10558%  
West Walker River below Little Walker7549%  
East Walker River near Bridgeport2134%  
Download in comma-delimited format
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B-120 Water Supply Forecast Summary (continued)
Water-Year (WY) Forecast Summary and Monthly Distribution (in thousands of acre-feet):
WatershedOct
thru
Jan
FebMarAprMayJunJulAugSepWater
Year
80%
Probability
Range
WY
%
Avg
Trinity, Lewiston15548471207527820483430 -53536%
Inflow to Shasta1,2862982903842852051761651563,2452,995 -3,45556%
Sacramento, Bend1,7834464305474102882352002064,5454,225 -4,89053%
Feather, Oroville7831812154083001429073642,2552,070 -2,43051%
Yuba, Smartsville3017510930921560169101,105975 -1,23549%
American, Folsom289771604462607014451,3251,180 -1,49550%
Cosumnes, Mich. Bar3493569186210175155 -21546%
Mokelumne, Pardee56193912212736511406355 -47054%
Stanislaus, Gdw.1153269190155501563635560 -73055%
Tuolumne, La Grange14436902612501001973910835 -1,00548%
Merced, McClure661642137108351030417365 -47042%
San Joaquin, Millerton1073353203250150471710870745 -99049%
Kings, Pine Flat125345419126015039149875740 -1,00051%
Kaweah, Terminus351114506028732210180 -23547%
Tule, Success1957151021005950 -7040%
Kern, Isabella1062529568570291510425380 -47058%
Download in comma-delimited format

Notes:

50 year averages are based on years 1966 to 2015.

Unimpaired runoff represents the natural water production of a river basin, unaltered by upstream diversions, storage, or by export or import of water
to or from other watersheds.  Groundwater changes due to human activity or not considered.  Forecasted runoff assumes median conditions subsequent to the date of forecast.  Runoff probability ranges are statistically derived from historical data.

The 80% probability range is comprised of the 90% exceedance level value and the 10% exceedance level value.

The actual runoff should fall within the stated limits eight times out of ten.

Forecast point names are based on USGS gage names.

For more information please contact:
Sean De Guzman(916) 574-2208
John King(916) 574-2637
Andy Reising(916) 574-2181
Ashok Bathulla(916) 574-2634
Lauren Miller(916) 574-1433
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