10336610  UPPER TRUCKEE RIVER AT SOUTH LAKE TAHOE, CA

LOCATION.--Lat 38°55'21", long 119°59'26", in NW 1/4 SE 1/4 sec.4, T.12 N., R.18 E., El Dorado County, Hydrologic
   Unit 16050101, on left bank 200 ft downstream from U.S. Highway 50 Bridge, 1.0 mi northeast of South Lake
   Tahoe Post Office, and 1.4 mi upstream from Lake Tahoe.

DRAINAGE AREA.--54.9 mi2.

                                               WATER-DISCHARGE RECORDS

PERIOD OF RECORD.--October 1971 to September 1974, October 1976 to June 1977, October 1977 to June 1978,
   March 1980 to current year.

GAGE.--Water-stage recorder.  Datum of gage is 6,229.04 ft above sea level.  Prior to Apr. 26, 1984, at datum
   2.00 ft higher.  Prior to Oct. 19, 1993, at site 200 ft upstream at same datum.

REMARKS.--Records fair including estimated periods.  Two small dams may cause slight regulation at times.  Some
   small diversions for domestic use upstream from station.  Echo Lake conduit (station 11434500) diverts from
   Echo Lake (station 10336608), to South Fork American River basin.  See schematic diagram of Truckee River
   basin.

EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 2,740 ft3/s, Mar. 8, 1986, gage height, 9.08 ft; maximum gage
   height, 10.12 ft, present datum, Feb. 16, 1982; minimum daily, 0.70 ft3/s, Aug. 22 to Sept. 5, 1994.

EXTREMES FOR CURRENT YEAR.--Peak discharges greater than base discharge of 300 ft3/s, or maximum:

                       Discharge       Gage height                              Discharge       Gage height
 Date       Time        (ft3/s)           (ft)            Date       Time        (ft3/s)           (ft)

Dec. 12     1315          562             5.02           Apr. 16     1500           497            4.74
Jan. 16     1815          351             4.06           May  16     1345          1780            7.97


                  DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1995 TO SEPTEMBER 1996
                                               DAILY MEAN VALUES

DAY       OCT      NOV      DEC      JAN      FEB      MAR      APR      MAY      JUN      JUL      AUG      SEP

  1     e41        9.2       11      106      e71       88      190      454      334      143       29     12
  2     e40      e12         12       82      e70       86      206      490      382      132       27     12
  3      39      e12         11       72      e70       94      170      477      455      129       26     12
  4      34       10         33       64     e200      e94      158      423      539      130       26     11
  5      34       10         44       58     e600      e94      160      398      541      122       25     10

  6     e34        9.7       28       53     e400      e94      175      419      512      113       25     11
  7      33        9.7       28       51      303      e95      203      410      547      112       24     12
  8     e32        9.8       26       50      242       95      246      461      553      109       23     11
  9      29       10         24       48      210       99      285      434      498      102       23     10
 10     e28        9.8       21       48      183      107      272      452      433       97       22     10

 11      23       10         47       45      165      126      246      487      372       89       22     10
 12      17        9.6      410       43      157      121      234      571      337       92       24     10
 13      14        9.6      223       42      154      107      208      631      370      100       28     10
 14      13        9.6      138       40      151       97      208      677      356       90       28     13
 15      12        9.6      101       48      149       97      248      822      319       82       25     14

 16      11        9.4       84      168     e148      105      419     1430      294       74       24     15
 17      10        9.7       76      144     e145      116      297     1060      265       66       22     14
 18       9.9      9.6       60       94     e142      136      289     1000      239       60       21     13
 19       9.7      9.5       56      e93     e140      159      216      657      232       56       20     13
 20       9.3      9.1       56      e91     e137      186      195      472      226       53       19     12

 21       8.6      9.1       67      e90     e134      200      173      426      221       51       18     11
 22       7.7      9.3       66      e88     e131      199      163      492      198       49       18     11
 23       8.2      9.3       54      e87     e128      171      182      450      186       48       17      9.9
 24       8.0      9.8       53      e85     e126      145      260      398      188       45       17      9.9
 25       8.6     10         48      e83     e123      132      313      352      197       37       18      9.4

 26       9.0     16         44      e81     e120      125      350      345      208       36       17     10
 27       8.7     12         41      e79     e110      141      395      389      192       35       16     10
 28       8.8     11         40      e77     e100      205      365      352      155       35       16     11
 29       8.6     11         37      e76      e90      150      329      307      143       35       16      9.9
 30       8.4     11         94      e74      ---      143      402      312      143       32       14      9.7
 31       9.5      ---      153      e73      ---      148      ---      306      ---       31       13      ---

TOTAL   567.0    306.4     2186     2333     4899     3955     7557    16354     9635     2385      663    336.8
MEAN     18.3     10.2     70.5     75.3      169      128      252      528      321     76.9     21.4     11.2
MAX        41       16      410      168      600      205      419     1430      553      143       29       15
MIN       7.7      9.1       11       40       70       86      158      306      143       31       13      9.4
AC-FT    1120      608     4340     4630     9720     7840    14990    32440    19110     4730     1320      668

  e Estimated.


                        10336610  UPPER TRUCKEE RIVER AT SOUTH LAKE TAHOE, CA--Continued

STATISTICS OF MONTHLY MEAN DATA FOR WATER YEARS 1972 - 1996, BY WATER YEAR (WY)

          OCT      NOV      DEC      JAN      FEB      MAR      APR      MAY      JUN      JUL      AUG      SEP

MEAN     15.8     41.3     49.6     51.6     70.9      107      164      302      253     89.5     21.5     13.3
MAX      72.1      225      218      165      307      305      300      567      795      448      102     55.3
(WY)     1983     1984     1982     1974     1986     1986     1982     1982     1983     1995     1983     1983
MIN      2.60     7.36     8.07     8.00     10.5     21.2     64.0     55.3     23.5     4.65     1.15     1.39
(WY)     1989     1991     1991     1991     1991     1977     1977     1977     1992     1994     1994     1988

SUMMARY STATISTICS           FOR 1995 CALENDAR YEAR        FOR 1996 WATER YEAR           WATER YEARS 1972 - 1996

ANNUAL TOTAL                       74570.4                    51177.2
ANNUAL MEAN                          204                        140                        101
HIGHEST ANNUAL MEAN                                                                        203              1983
LOWEST ANNUAL MEAN                                                                          29.2            1988
HIGHEST DAILY MEAN                  1180     May  1            1430     May 16            2010       Feb 16 1982
LOWEST DAILY MEAN                      7.7   Oct 22               7.7   Oct 22                .70    Aug 22 1994
ANNUAL SEVEN-DAY MINIMUM               8.4   Oct 21               8.4   Oct 21                .70    Aug 22 1994
INSTANTANEOUS PEAK FLOW                                        1780     May 16            2740       Mar  8 1986
INSTANTANEOUS PEAK STAGE                                          7.97  May 16              10.12    Feb 16 1982
ANNUAL RUNOFF (AC-FT)             147900                     101500                      72930
10 PERCENT EXCEEDS                   621                        398                        276
50 PERCENT EXCEEDS                    84                         80                         38
90 PERCENT EXCEEDS                    10                          9.9                        7.1

                        10336610  UPPER TRUCKEE RIVER AT SOUTH LAKE TAHOE, CA--Continued

                                              WATER-QUALITY RECORDS

PERIOD OF RECORD.--Water years 1972-74, 1978, 1980 to current year.

PERIOD OF DAILY RECORD.--
  SPECIFIC CONDUCTANCE:  March 1981 to September 1983.
  WATER TEMPERATURE:  October 1971 to June 1974, October 1977 to June 1978, March 1980 to September 1992.
  SUSPENDED-SEDIMENT DISCHARGE:  October 1971 to June 1974, October 1977 to June 1978, March 1980 to
   September 1992.

REMARKS.--In October 1992, station was incorporated into the expanded Lake Tahoe Interagency Monitoring Program
  to monitor tributary contributions of nutrients and sediment to Lake Tahoe.  In May 1994, station was
  incorporated into the National Water-Quality Assessment Program (NAWQA) to monitor water-quality conditions in
  the Pyramid and Winnemucca Lake Basin.  These data are reviewed and provided by the Nevada District Office,
  U.S. Geological Survey.


                          WATER-QUALITY DATA, WATER YEAR OCTOBER 1995 TO SEPTEMBER 1996

	                       DIS-              PH                        BARO-            OXYGEN,   NITRO-
	                     CHARGE,   SPE-     WATER                      METRIC             DIS-     GEN,
	                      INST.    CIFIC    WHOLE                      PRES-             SOLVED  NO2+NO3
	                      CUBIC    CON-     FIELD   TEMPER-  TEMPER-    SURE   OXYGEN,   (PER-     DIS-	
	                       FEET    DUCT-   (STAND-   ATURE    ATURE     (MM      DIS-     CENT    SOLVED
	    DATE      TIME     PER     ANCE      ARD      AIR     WATER      OF     SOLVED   SATUR-   (MG/L
	                      SECOND  (US/CM)   UNITS)  (DEG C)  (DEG C)    HG)     (MG/L)   ATION)   AS N)
	                     (00061)  (00095)  (00400)  (00020)  (00010)  (00025)  (00300)  (00301)  (00631)

	OCT
	  12...       1040     21          51      7.7     12.0      8.5      605      9.0       97    0.014	
	NOV
	  21...       1125      9.4        93     --       11.5      6.0     --       --       --      0.018
	DEC
	  11...       1410     35          60     --        4.5      3.5     --       --       --      0.036
	  12...       1320    562          35     --        3.0      3.0     --       --       --      0.020
	  14...       1200    135          34     --        3.0      3.0     --       --       --      0.024
	JAN
	  12...       1100     43          57     --        5.5      1.5     --       --       --      0.018
	  16...       1325    174          58     --        4.0      2.0     --       --       --      0.023
	  17...       1410    123          53     --        1.5      2.0     --       --       --      0.019
	FEB
	  04...       1445    226          61     --        4.5      0.5     --       --       --      0.031
	  05...       1500    506          36     --        7.0      0.5     --       --       --      0.019
	  09...       1400    204          50     --        9.0      3.0     --       --       --      0.021
	MAR
	  08...       1015     93          74      7.3      2.0      1.0      609     10.6       93    0.032
	  20...       1040    173          63     --       11.0      3.0     --       --       --      0.023
	APR
	  05...       1300    149          66     --       11.5      6.0     --       --       --      0.023
	  12...       1735    226          49      7.5      4.0      7.0      601      9.6      100    0.009
	  16...       1550    492          47     --        4.0      3.5     --       --       --      0.014
	  17...       1110    286          49     --        3.5      2.5     --       --       --      0.018
	  25...       1215    297          43     --       12.0      6.0     --       --       --      0.010
	MAY
	  02...       0830    517          29     --        9.0      3.0     --       --       --      0.008
	  06...       1100    423          30     --       15.0      4.0     --       --       --      0.009
	  06...       1925    385          31     --       10.0      6.5     --       --       --      0.008
	  11...       1240    472          28     --       17.0      6.5     --       --       --      0.008
	  14...       0830    716          23      7.6     13.0      5.5      603      9.7       97    0.003
	  15...       0920    795          22     --       14.0      6.0     --       --       --      0.007
	  15...       1520    906          23     --       15.0      8.5     --       --       --      0.005
	  16...       1445   1750          22     --       10.0      7.0     --       --       --      0.007
	  17...       1900    923          22     --        6.5      5.0     --       --       --      0.009
	  18...       1430   1100          24     --        8.0      7.0     --       --       --      0.007
	  21...       1140    412          31      7.5      9.5      5.0     --       --       --      0.008
	  30...       1315    294          33     --       15.0      7.0     --       --       --      0.008
	JUN
	  03...       1625    391          29     --       26.0     12.0     --       --       --      0.007
	  06...       0930    522          24      7.4     17.0      8.0      608      9.8      104    0.006
	  06...       2100    491          25     --       16.5     12.5     --       --       --      0.004
	  12...       1210    331          27     --       17.0     11.0     --       --       --      0.006
	  18...       1150    239          30     --       17.5     10.5     --       --       --      0.007
	  26...       1105    201          33     --        9.0      8.0     --       --       --      0.007
	JUL
	  03...       1110    130          35     --       23.5     13.5     --       --       --      0.008
	  19...       1320     57          51      7.8     20.0     16.0      609      8.4      107    0.002
	AUG
	  16...       1030     24          77     --       23.0     17.0     --       --       --      0.003
	SEP
	  06...       1115     11          96      7.8     14.0     12.0      605      9.4      110    0.008



                        10336610  UPPER TRUCKEE RIVER AT SOUTH LAKE TAHOE, CA--Continued

                          WATER-QUALITY DATA, WATER YEAR OCTOBER 1995 TO SEPTEMBER 1996

	             NITRO-   NITRO-                     PHOS-    IRON,             SEDI-     SED.	
	              GEN,   GEN,AM-            PHOS-   PHORUS    BIO.              MENT,     SUSP.
	            AMMONIA  MONIA +   PHOS-   PHORUS    ORTHO,   REACT-   SEDI-     DIS-    SIEVE
	              DIS-   ORGANIC  PHORUS     DIS-    DIS-      IVE     MENT,   CHARGE,    DIAM.
	             SOLVED   TOTAL    TOTAL    SOLVED  SOLVED    TOTAL    SUS-      SUS-   % FINER	
	    DATE     (MG/L    (MG/L    (MG/L    (MG/L   (MG/L    (UG/L     PENDED   PENDED    THAN
	             AS N)    AS N)    AS P)    AS P)   AS P)     AS FE)   (MG/L)  (T/DAY)  .062 MM
	            (00608)  (00625)  (00665)  (00666)  (00671)  (46568)  (80154)  (80155)  (70331)

	OCT
	  12...       0.001     0.07    0.015    0.009    0.004      215       12     0.68     --
	NOV
	  21...       0.002     0.12    0.015    0.009    0.009      289        1     0.02     --
	DEC
	  11...       0.027     0.15    0.044    0.025    0.017      470       14     1.3      --
	  12...       0.013     0.70    0.222    0.031    0.021     1770      124   188        --
	  14...       0.003     0.18    0.022    0.009    0.002      445       15     5.5      --
	JAN
	  12...      <0.001     0.10    0.013     --      0.005      276        2     0.23     --
	  16...      <0.001     0.73    0.221     --      0.009     3270      137    64        --
	  17...       0.006     0.24    0.029     --      0.004      543       20     6.6      --
	FEB
	  04...       0.008     0.18    0.048     --      0.004      912       34    21        --
	  05...       0.006     0.17    0.113     --      0.009     1530      458   626        --
	  09...       0.002     0.17    0.028     --      0.007      647       17     9.4      --
	MAR
	  08...       0.015     0.08    0.024     --      0.006      637       25     6.3      --
	  20...       0.005     0.13    0.032     --      0.004      514       28    13        --
	APR
	  05...      <0.001     0.06    0.017     --      0.006      353        7     2.8      --
	  12...       0.001     0.15    0.023     --      0.004      265        8     4.9      --
	  16...       0.005     0.16    0.055     --      0.010     2500       77   102        --
	  17...       0.002     0.18    0.027     --      0.005      676       34    26        --
	  25...       0.001     0.15    0.034     --      0.005      444       22    18        --
	MAY
	  02...       0.003     0.10    0.048     --      0.005     1890       44    61        --
	  06...        --       --      0.023     --      0.003     --         47    54        --
	  06...       0.003     0.14    0.034     --      0.004      463       18    19        --
	  11...       0.001     0.34    0.025     --      0.005      621       14    18        --
	  14...       0.004     0.18    0.056     --      0.003     1380       46    89        --
	  15...       0.004     0.16    0.041     --      0.005      445       61   131        --
	  15...       0.005     0.30    0.060     --      0.011      911       56   137        --
	  16...       0.008     0.36    0.133     --      0.014     2100      118   558          34
	  17...       0.001     0.23    0.060     --      0.005      901       55   137        --
	  18...       0.002     0.15    0.043     --      0.008      463       21    62        --
	  21...       0.002     0.20    0.036     --      0.004      507       19    21        --
	  30...       0.001     0.12    0.027     --      0.005      295       14    11        --
	JUN
	  03...       0.004     0.25    0.030     --      0.004      250       19    20        --
	  06...       0.002     0.16    0.021     --      0.004      251       28    39        --
	  06...       0.002     0.20    0.024     --      0.005      323       33    44        --
	  12...       0.002     0.18    0.026     --      0.005      459       15    13        --
	  18...      <0.001     0.10    0.026     --      0.005      526       10     6.5      --
	  26...       0.002     0.13    0.029     --      0.005      317        6     3.3      --
	JUL
	  03...       0.001     0.11    0.028     --      0.006      318       12     4.2      --
	  19...      <0.001     0.07    0.038     --      0.006      228        7     1.1      --
	AUG
	  16...      <0.001     0.05    0.019     --      0.004       53       11     0.71     --
	SEP
	  06...      <0.001     0.13    0.028     --      0.003      352        6     0.18     --