Water-Data Report 2008 11453900 near Winters, CA Basin

LOCATION.--Lat 38°3048, long 122°0613 referenced to North American Datum of 1927, in SE ¼ NW ¼ sec.29, T.8 N., R.2 W., Napa County, CA, Hydrologic Unit 18020117, near center of on , and 7.4 mi west of Winters. DRAINAGE AREA.--566 mi². SURFACE-WATER RECORDS PERIOD OF RECORD.--January 1957 to current year. REVISED RECORDS.--WSP 1735: 1958-60. WSP 1931: Drainage area. GAGE.--Water-stage recorder. Datum of gage is NGVD of 1929 (levels by U.S. Bureau of Reclamation). COOPERATION.--Records provided by U.S. Bureau of Reclamation. Total evaporation provided by U.S. Bureau of Reclamation, not reviewed by U.S. Geological Survey. REMARKS.--Reservoir is formed by concrete arch-gravity dam completed November 1956. Usable capacity, 1,592,000 acre-ft, between elevations 253.25 ft, invert of outlet valves, and 440 ft, crest of glory-hole spillway. Dead storage, 10,340 acre-ft. Water is released down Putah Creek and is diverted into Putah South Canal (station 11454210) for irrigation of about 46,000 acres in the lower . Total diverted during current year was 214,400 acre-ft. Releases for irrigation began in May 1959. Records, including extremes, show total contents at 2400 hours. See schematic diagram of lower Sacramento River Basin available from the Water Science Center. EXTREMES FOR PERIOD OF RECORD.--Maximum contents, 1,733,500 acre-ft, Mar. 2, 1983, elevation, 446.67 ft; minimum since irrigation pool first filled, 422,130 acre-ft, Dec. 1, 1992, elevation, 361.73 ft. EXTREMES FOR CURRENT YEAR.--Maximum contents, 1,404,300 acre-ft, Mar. 13, 15, 16, elevation, 429.46 ft; minimum, 1,151,000 acre-ft, Sept. 30, elevation, 415.02 ft.

Capacity table (elevation, in feet, and contents, in acre-feet) (Based on survey by U.S. Bureau of Reclamation in 1956) Elevation Contents Elevation Contents Elevation Contents 360 404,550 390 765,730 420 1,236,000 370 511,760 400 911,200 430 1,414,200 380 632,360 410 1,068,100 450 1,799,900

U.S. Department of the Interior U.S. Geological Survey Water-Data Report 2008 11453900 Lake Berryessa near Winters, CA—Continued

RESERVOIR STORAGE, ACRE FEET WATER YEAR OCTOBER 2007 TO SEPTEMBER 2008 DAILY OBSERVATION AT 2400 HOURS Day Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep

1 1,242,700 1,231,100 1,222,000 1,219,900 1,340,200 1,400,600 1,395,900 1,364,000 1,324,200 1,277,300 1,227,200 1,182,000 2 1,241,900 1,231,000 1,221,800 1,219,900 1,346,900 1,401,400 1,395,300 1,363,100 1,322,700 1,275,500 1,225,600 1,180,600 3 1,241,300 1,230,800 1,221,800 1,219,700 1,357,800 1,401,900 1,394,600 1,362,000 1,321,300 1,274,300 1,223,900 1,179,200 4 1,240,100 1,230,400 1,222,300 1,253,800 1,361,100 1,402,500 1,394,100 1,361,100 1,319,500 1,272,400 1,222,500 1,178,200 5 1,239,800 1,230,100 1,221,300 1,260,700 1,363,400 1,402,800 1,393,300 1,360,700 1,318,300 1,271,000 1,220,800 1,177,200 6 1,238,200 1,229,900 1,221,500 1,265,200 1,364,200 1,403,000 1,391,700 1,359,300 1,316,700 1,269,600 1,219,200 1,175,900 7 1,237,700 1,229,600 1,222,700 1,265,200 1,366,200 1,403,000 1,390,100 1,358,000 1,314,900 1,268,300 1,217,800 1,174,800 8 1,236,700 1,229,600 1,221,500 1,269,000 1,366,900 1,403,400 1,389,700 1,357,500 1,314,000 1,266,600 1,216,300 1,173,800 9 1,236,000 1,229,100 1,221,500 1,269,200 1,367,400 1,403,800 1,389,000 1,355,900 1,313,000 1,264,800 1,214,600 1,172,300 10 1,236,100 1,229,200 1,220,900 1,271,300 1,369,000 1,403,900 1,387,700 1,354,400 1,310,600 1,263,500 1,213,200 1,171,100 11 1,235,400 1,229,700 1,220,400 1,271,500 1,369,000 1,403,900 1,386,600 1,353,700 1,308,700 1,261,700 1,211,800 1,169,900 12 1,235,800 1,228,900 1,220,300 1,272,700 1,368,300 1,404,100 1,385,700 1,353,200 1,307,300 1,260,000 1,210,500 1,169,100 13 1,235,400 1,229,200 1,219,700 1,272,500 1,369,000 1,404,300 1,385,700 1,351,600 1,306,000 1,258,000 1,209,100 1,167,600 14 1,234,900 1,228,700 1,219,700 1,273,600 1,369,800 1,403,900 1,377,700 1,350,300 1,304,400 1,256,800 1,207,900 1,166,500 15 1,235,100 1,228,400 1,219,600 1,273,600 1,369,800 1,404,300 1,382,100 1,348,700 1,302,800 1,254,900 1,206,200 1,165,700 16 1,235,100 1,228,700 1,219,600 1,273,400 1,370,100 1,404,300 1,381,000 1,347,800 1,301,300 1,253,300 1,204,600 1,164,000 17 1,234,400 1,228,000 1,219,700 1,272,500 1,370,500 1,404,100 1,379,700 1,346,500 1,299,700 1,251,800 1,203,100 1,162,700 18 1,234,800 1,228,000 1,219,900 1,273,100 1,370,300 1,404,100 1,378,400 1,345,100 1,297,900 1,249,800 1,201,500 1,162,200 19 1,234,600 1,227,700 1,220,400 1,273,200 1,371,200 1,403,800 1,377,200 1,343,600 1,296,300 1,248,600 1,200,200 1,160,800 20 1,234,200 1,227,300 1,221,800 1,273,200 1,371,000 1,403,900 1,375,700 1,342,200 1,294,700 1,246,600 1,199,000 1,160,100 21 1,233,400 1,227,000 1,221,600 1,273,400 1,371,600 1,403,600 1,375,200 1,340,200 1,293,100 1,244,600 1,197,500 1,159,000 22 1,233,200 1,226,500 1,221,300 1,274,700 1,371,600 1,403,600 1,373,600 1,338,300 1,291,500 1,243,300 1,196,300 1,158,300 23 1,233,400 1,225,900 1,221,600 1,273,800 1,372,500 1,402,500 1,372,300 1,337,000 1,289,900 1,241,900 1,194,900 1,157,400 24 1,233,000 1,226,100 1,221,300 1,273,600 1,389,200 1,402,100 1,371,400 1,335,800 1,288,200 1,240,100 1,193,700 1,155,900 25 1,232,900 1,225,600 1,221,500 1,287,300 1,394,400 1,402,100 1,370,300 1,334,200 1,286,800 1,238,600 1,192,200 1,155,100 26 1,232,700 1,225,400 1,221,500 1,310,300 1,396,300 1,400,600 1,369,600 1,332,900 1,285,400 1,236,700 1,191,300 1,154,200 27 1,231,600 1,225,400 1,220,600 1,319,400 1,398,300 1,399,900 1,368,500 1,331,300 1,283,800 1,235,100 1,189,400 1,153,400 28 1,232,300 1,224,600 1,220,400 1,324,300 1,399,200 1,399,000 1,367,600 1,329,700 1,282,000 1,233,400 1,188,200 1,152,200 29 1,231,300 1,223,400 1,220,900 1,326,500 1,400,300 1,398,300 1,366,300 1,328,400 1,280,400 1,231,600 1,186,900 1,151,700 30 1,231,500 1,222,800 1,220,900 1,329,000 --- 1,397,500 1,364,900 1,326,700 1,278,900 1,230,300 1,185,300 1,151,000 31 1,231,300 --- 1,219,700 1,334,500 --- 1,396,600 --- 1,325,800 --- 1,228,700 1,183,500 --- Max 1,242,700 1,231,100 1,222,700 1,334,500 1,400,300 1,404,300 1,395,900 1,364,000 1,324,200 1,277,300 1,227,200 1,182,000 Min 1,231,300 1,222,800 1,219,600 1,219,700 1,340,200 1,396,600 1,364,900 1,325,800 1,278,900 1,228,700 1,183,500 1,151,000 Elevation, in feet, at end of month 419.73 419.24 419.06 425.60 429.24 429.04 427.29 425.11 422.46 419.58 416.94 415.02 Change in contents, in acre-feet -12,000 -8,500 -3,100 +114,800 +65,800 -3,700 -31,700 -39,100 -46,900 -50,200 -45,200 -32,500 Total evaporation, in acre-feet 3,529 1,880 1,755 829 1,585 4,092 5,939 8,097 9,239 9,640 9,654 6,859

Calendar Year 2007 Water Year 2008 Change in contents, in acre-feet -216,000 -92,300

— 2 — Water-Data Report 2008 11453900 Lake Berryessa near Winters, CA—Continued

1,450,000

1,400,000

1,350,000

1,300,000

1,250,000 OBSERVATION AT 2400 HOURS RESERVOIR STORAGE, ACRE FEET, RESERVOIR STORAGE, ACRE

1,200,000

1,150,000 O N D J F M A M J J A S 2007 2008

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