11444500 SOUTH FORK AMERICAN RIVER NEAR PLACERVILLE, CA

LOCATION.-Lat 38°46'16", long 120°48'55", in NE 1/4 SW 1/4 sec.25, T.11 N., R.10 E., El Dorado County, Hydrologic Unit 18020129, on right bank 700 ft 
downstream from Chili Bar Dam, 0.5 mi upstream from Big Canyon, and 2.5 mi north of Placerville. 
DRAINAGE AREA.-598 mi2. 
PERIOD OF RECORD.-August 1911 to July 1920 (monthly discharge only for some periods, published in WSP 1315-A), July 1964 to current year. 
REVISED RECORDS.-WSP 1931: Drainage area. 
GAGE.-Water-stage recorder. Elevation of gage is 925 ft above sea level, from topographic map. Aug. 11, 1911, to July 31, 1920, nonrecording gage 0.6 mi 
downstream at different datum. 
REMARKS.-Flow regulated by Chili Bar Reservoir, capacity, 3,700 acre-ft, Chili Bar Powerplant, and other storage and powerplants (see station 11443500). See 
schematic diagrams of South Fork American River and lower Sacramento River Basins. 
COOPERATION.-Records provided by Pacific Gas & Electric Co., under general supervision of the U.S. Geological Survey, in connection with a Federal Energy 
Regulatory Commission project. 
EXTREMES FOR PERIOD OF RECORD.-Maximum discharge, 71,000 ft3/s, Jan. 2, 1997, gage height, unknown, on basis of computations of flow over dam, maximum 
gage height, 17.4 ft, from floodmarks, datum then in use, Dec. 23, 1964; minimum daily, 0.2 ft3/s, Nov. 12, 1964. 

                  DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1997 TO SEPTEMBER 1998

                                               DAILY MEAN VALUES
 
DAY       OCT      NOV      DEC      JAN      FEB      MAR      APR      MAY      JUN      JUL      AUG      SEP
 
  1       926      330     e608      242      870     2410     3540     4170     3740    e5770     2070     1940
  2       926      435     e634      991     2020     2970     3270     4220     4150    e5630     1690     1500
  3       947      358     e206      591     4460     2980     2970     4080     4000     4450     1720     1820
  4       690      666     e165      924     3020     2180     3460     4270     3700     4330     2760     1270
  5       656      683     e162     1290     2530     1850     2130     4370     4010     4180     1980     1490
 
  6       858      428     e656     1450     2950     1940     3390     4420     3740     4250     1320     1810
  7       808      483    e1330     1320     4060     2310     3310     4240     5420     3920     1890     1720
  8       599      431    e1050     1140     4900     2690     2920     4050     5420     3840     1830      933
  9      1250      304     e994      994     3450     2650     3220     3590     4910     3900      899     1480
 10       500      607     e839     1350     2990     1950     3610     3640     5130     3830     1430     1840
 
 11       470      489     e196     2190     2870     2110     2880     3510     5320     4040     2080     1590
 12       512      635     e778     4020     2730     2050     2520     4020     4990     3920     2020     1910
 13       911      394      647     2890     2890     2100     3960     3640     6710     3170     2200     1680
 14       680      303      737     1970     3290     1890     3380     3400     6430     3410     1500     1490
 15       420      627      638     4510     3480     2260     3420     3520     6500     2470     1490     1490
 
 16       612      210      617     4710     3070     2570     2920     3470     6820     3030     1350     1460
 17       504      848      973     4330     2940     2620     2830     3420     6750     2470     1570     1290
 18       500      258      504     3760     2720     2710     2650     3160     6480     2520     1680     1240
 19       482      145      744     3750     3050     3110     3090     3370     6030     2320     1550     1500
 20       565      487      769     2200     3770     3210     3340     3480     6030     2650     1640     1570
 
 21       863      986      731     1130     3780     2810     3220     3040     6530     2520     1610     1260
 22      1120      208     1090     1710     3860     2880     3330     3880     6480     2040     1910     1230
 23       640      407      819     1610     3790     3530     3220     3330     6210     2610     1820      961
 24       522      417      821     1640     3240     6330     3850     3160     5670     2760     1750     1100
 25       468      502      167     1910     2810     7260     4190     3200     5220     2200     1850     1030
 
 26       455      925      844     1420     2040     5330     3990     3940     5280     1840     1610      804
 27       620     e540      672     1040     2840     4510     3570     3990     5220     2030     1600      672
 28       686     e285      551     1070     1770     4450     3830     3720     5210     2010     1320     1060
 29       420     e790      527     1600      ---     4120     4200     3840    e6210     1890     1490     1240
 30       891     e513      655     1210      ---     4010     3940     4070    e5850     2030     1340      691
 31      1020      ---      566     1300      ---     4210      ---     3360      ---     2030     2320      ---
 
TOTAL   21521    14694    20690    60262    86190    98000   100150   115570   164160    98060    53289    41071
MEAN      694      490      667     1944     3078     3161     3338     3728     5472     3163     1719     1369
MAX      1250      986     1330     4710     4900     7260     4200     4420     6820     5770     2760     1940
MIN       420      145      162      242      870     1850     2130     3040     3700     1840      899      672
AC-FT   42690    29150    41040   119500   171000   194400   198600   229200   325600   194500   105700    81460
    e  Estimated.


STATISTICS OF MONTHLY MEAN DATA FOR WATER YEARS 1965 - 1998, BY WATER YEAR (WY)                                 
          OCT      NOV      DEC      JAN      FEB      MAR      APR      MAY      JUN      JUL      AUG      SEP
MEAN      516      764     1304     1892     1795     1944     2058     2528     2035     1208      955      833
MAX       935     3806     5386     9673     6613     5561     5382     6159     6496     3648     1719     1401
(WY)     1984     1984     1965     1997     1986     1983     1982     1995     1983     1983     1998     1995
MIN       204      106      320      188      125      124      255      295      228     88.2      142      244
(WY)     1988     1978     1977     1977     1977     1977     1977     1977     1977     1977     1977     1977
 
SUMMARY STATISTICS           FOR 1997 CALENDAR YEAR        FOR 1998 WATER YEAR           WATER YEARS 1965 - 1998
 
ANNUAL TOTAL                      794926                     873657                                             
ANNUAL MEAN                         2178                       2394                       1484                  
HIGHEST ANNUAL MEAN                                                                       3275              1983
LOWEST ANNUAL MEAN                                                                         224              1977
  HIGHEST DAILY MEAN                 57100     Jan  2            7260     Mar 25           57100       Jan  2 1997
  LOWEST DAILY MEAN                    145     Nov 19             145     Nov 19                .20    Nov 12 1964
  ANNUAL SEVEN-DAY MINIMUM             398     Nov 13             398     Nov 13              20       Feb 11 1977
  INSTANTANEOUS PEAK FLOW                                        8970     Mar 24           71000       Jan  2 1997
  INSTANTANEOUS PEAK STAGE                                          9.98  Mar 24              17.40    Dec 23 1964
ANNUAL RUNOFF (AC-FT)            1577000                    1733000                    1075000                  
10 PERCENT EXCEEDS                  3950                       4430                       3360                  
50 PERCENT EXCEEDS                  1330                       2030                       1000                  
90 PERCENT EXCEEDS                   501                        513                        337