11465000 DRY CREEK BELOW WARM SPRINGS DAM, NEAR GEYSERVILLE, CA

LOCATION.-Lat 38°43'11", long 122°59'58", in Tzabaco Grant, Sonoma County, Hydrologic Unit 18010110, on right bank of outlet channel, 500 ft downstream 
from Warm Springs Dam, 500 ft upstream from county road bridge, and 5.0 mi west of Geyserville. 
DRAINAGE AREA.-131 mi2. 
PERIOD OF RECORD.-October 1939 to September 1942 (published as "Dry Creek near Healdsburg"), October 1981 to current year. 
  WATER TEMPERATURE RECORD: Water years 1981-94. 
GAGE.-Water-stage recorder and concrete control. Datum of gage is 188.21 ft above sea level (levels by U.S. Army Corps of Engineers). Prior to Sept. 30, 1942, 
nonrecording gage at site 500 ft downstream at different datum. 
REMARKS.-Records good. Flow affected by storage in Lake Sonoma, capacity, 380,600 acre-ft, beginning October 1983. See schematic diagram of Russian River Basin. 

EXTREMES FOR PERIOD OF RECORD.-Maximum discharge, 22,500 ft3/s, Feb. 28, 1940, gage height, 16.9 ft, datum then in use; no flow Oct.1 to Dec. 8, 1939. 
Maximum discharge since regulation by Lake Sonoma, 5,590 ft3/s, Feb. 11, 1998, gage height, 10.38 ft;  minimum daily, 6.3 ft3/s July 10, 
1984. 
EXTREMES OUTSIDE PERIOD OF RECORD.-Flood of December 1937 reached a stage of 21.8 ft from floodmarks, discharge about      25,000 ft3/s. 

                  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       101      131      115       99     1510     4500      523      173      223      102      100       99
  2       100      130      115       84      229     3920      523      173      313      102      100       99
  3        98      130      116       86      220     2710      523      173      308      102      100       99
  4        78      130      115       93      221     1420      523      173      308      102      100      100
  5        49      130      111       91      477      937      523      173      283      102      100      100
 
  6        29      129      109       96      121      475      523      173      304      102      100      100
  7        28      129      112       96       95      250      523      173      304      101      100      100
  8        28      129      113       96       90      250      524      174      305      101      100      100
  9        28      129      115       96     1910      250      525      174      305      101      100      100
 10        28      129      115       97     4160      162      425      174      304      101      100       95
 
 11        28      129      115       99     5300      136      258      131      304      101      100      104
 12        28      129      115       94     3240      138      256       94      304      101      100      103
 13        28      129      116       87     3010      138      256       94      304      101      100      103
 14        28      128      118      129     3760      136      256       95      304      100      100      102
 15        28      129      116      186     5000      136      256       94      305      100      100      103
 
 16        35      139      124      186     4970      304      256       95      308      100      100      103
 17        60      131      121      186     4920      551      256       95      310      100      100      103
 18        93      132      121      191     4800      555      257       95      309      100      100      102
 19        96      131      121     1160     1960      549      259       95      308      100      100      102
 20       123      131      121     2030      142      363      259       95      308      100      100      102
 
 21       144      131      121      740      152      178      259       95      308      100      100      102
 22       135      131      120      187      863      179      259       95      308      100      100      102
 23       117      131      124      961     2580      180      259       95      308      100      100      101
 24       117      132      119     3130     4390     1160      259       95      307      100      100      101
 25       120      131      119     2670     4580     2260      259       98      228      100      100      101
 
 26       117      131      119      963     4540     1010      259       95      181      100      100      101
 27       117      115      119      148     4530      653      229       95      182       99      100      101
 28       116      115      119      489     4550     1210      175       96      182      100      100      100
 29       116      117      116     1030      ---     1210      174      147      147      100      100       97
 30       116      115      112     2120      ---      902      173      181      106      100      100       96
 31       122      ---      109     3290      ---      523      ---      182      ---      100       99      ---
 
TOTAL    2451     3853     3621    21010    72320    27345    10009     3990     8278     3118     3099     3021
MEAN     79.1      128      117      678     2583      882      334      129      276      101      100      101
MAX       144      139      124     3290     5300     4500      525      182      313      102      100      104
MIN        28      115      109       84       90      136      173       94      106       99       99       95
AC-FT    4860     7640     7180    41670   143400    54240    19850     7910    16420     6180     6150     5990
 


STATISTICS OF MONTHLY MEAN DATA FOR WATER YEARS 1984 - 1998, BY WATER YEAR (WY)                                 
 
          OCT      NOV      DEC      JAN      FEB      MAR      APR      MAY      JUN      JUL      AUG      SEP
MEAN     79.5      157      199      462      533      405      174     94.7      115      118      110     89.5
MAX       120      524     1501     1986     2583     1494      948      265      276      274      169      122
(WY)     1997     1984     1984     1997     1998     1995     1995     1995     1998     1987     1987     1996
MIN      7.70     50.8     49.8     49.3     73.3     25.0     23.0     26.1     25.1     27.0     42.0     39.0
(WY)     1984     1986     1986     1986     1988     1985     1985     1985     1985     1985     1985     1985
 
SUMMARY STATISTICS           FOR 1997 CALENDAR YEAR        FOR 1998 WATER YEAR           WATER YEARS 1984 - 1998
 
ANNUAL TOTAL                      112884                     162115                                             
ANNUAL MEAN                          309                        444                        210                  
HIGHEST ANNUAL MEAN                                                                        512              1995
LOWEST ANNUAL MEAN                                                                          46.0            1985
  HIGHEST DAILY MEAN                  3990     Jan  8            5300     Feb 11            5300       Feb 11 1998
  LOWEST DAILY MEAN                     28     Oct  7              28     Oct  7               6.1     Oct 21 1983
  ANNUAL SEVEN-DAY MINIMUM              28     Oct  7              28     Oct  7               6.3     Oct 18 1983
  INSTANTANEOUS PEAK FLOW                                        5590     Feb 11            5590       Feb 11 1998
  INSTANTANEOUS PEAK STAGE                                         10.38  Feb 11              10.38    Feb 11 1998
ANNUAL RUNOFF (AC-FT)             223900                     321600                     152000                  
10 PERCENT EXCEEDS                   189                        947                        226                  
50 PERCENT EXCEEDS                   116                        121                        100                  
90 PERCENT EXCEEDS                    96                         95                         40