STATION NAME:  RIO GRANDE RIVER AT FOSTER RANCH NEAR LANGTRY, TDRAINAGE AREA
STATION NUMBER:  08377200           
STATE: TEXAS                      
COUNTY: VAL VERDE
                         



               STATISTICAL SUMMARY OF SELECTED WATER QUALITY DATA COLLECTED FROM OCT  1973 TO  AUG   1994


                                                                                       PERCENT OF SAMPLES IN WHICH VALUES
                                              DESCRIPTIVE STATISTICS                  WERE LESS THAN OR EQUAL TO THOSE SHOWN
 ------------------------------------- --------------------------------------  ------------------------------------------------------
                                       SAMPLE                                                          (MEDIAN)
     #WATER-QUALITY CONSTITUENT         SIZE    MAXIMUM    MINIMUM       MEAN      95 %       75 %       50 %       25 %        5 %
 ------------------------------------- --------------------------------------  ------------------------------------------------------
 FIELD MEASUREMENTS

 00061 DISCHARGE, INST. CFS              104  13000.000     26.000   1975.596    6872.500   2395.000   1115.000    807.000    467.750
 00095 SPECIFIC CONDUCT US/CM @ 25C      176   1840.000    444.000   1184.017    1640.000   1320.000   1150.000   1010.000    781.700
 00010 WATER TEMPERATUR (DEGREES)        137     31.000      3.500     20.901      28.500     27.000     22.000     15.000     11.450
 00400 PH, WH, FIELD    (STANDARD UNIT   176      8.500      7.100      7.882       8.315      8.100      7.900      7.700      7.400
 00410 ALKALINITY,WH,FE (MG/L AS CACO3   154    190.000     95.000    151.636     179.250    164.000    151.500    142.500    117.500
 00453 BICARBONATE,DIS, (MG/L AS HCO3)    28    215.000    133.000    180.536     211.850    196.500    182.500    165.750    138.850
 00452 CARBONATE,DIS,IT (MG/L AS CO3)     28      9.000      0.000      2.000       8.550      5.000      0.000      0.000      0.000
 39086 ALKALINITY,DIS,I (MG/L AS CACO3    20    186.000    109.000    149.750     185.500    163.750    151.500    138.000    109.550
 00300 OXYGEN DISSOLVED (MG/L)           136     12.800      6.600      8.961      11.515      9.600      8.800      8.200      7.400
 00301 OXYGEN DIS. PERC % OF SATURATIO   135    141.000     71.000    102.526     125.400    110.000     99.000     96.000     84.800

 BACTERIA

 31625 COLIFORM FECAL 0 COLS./100 ML     113   8400.000      1.000    912.177    5020.004    620.000    180.000     24.000      5.400
 31673 FECAL STRPT KF A COLS./100 ML     113  10000.000      6.000   1032.823    5220.004    820.000    250.000     52.000     11.700

 NUTRIENTS

 00631 NO2 + NO3 DISSOL (MG/L AS N)      108      1.900      0.072      0.808       1.355      1.000      0.830      0.592      0.173
 00608 NITROGEN AMMONIA (MG/L AS N)       76      0.240     <0.010      0.037*      0.120      0.040      0.020      0.010     <0.010
 00613 NITROGEN,NITRITE MG/L AS N         35      0.020     <0.010      0.005*      0.020     <0.010     <0.010     <0.010     <0.010
 00671 PHOSPHORUS ORTHO (MG/L AS P)       54      0.070     <0.010      0.012*      0.050      0.020     <0.010     <0.010     <0.010
 00666 PHOSPHORUS DISS. (MG/L AS P)      101      0.360     <0.010      0.023*      0.070      0.020      0.010     <0.010     <0.010
 00625 NITROGEN A+O TOT. (MG/L AS N)     136     13.000      0.100      1.202       4.590      1.000      0.700      0.400      0.200
 00665 PHOSPHORUS TOTAL (MG/L AS P)      136      5.800     <0.010      0.449*      2.600      0.360      0.100      0.030     <0.010

                                                                                                                         
 CFS          = CUBIC FEET PER SECOND                                 A+O          = AMMONIA PLUS ORGANIC
 US/CM @ 25C  = MICROSEIMENS PER CENTIMETER AT 25 DEGREES CELSIUS     N            = NITROGEN
 MG/L         = MILLIGRAMS PER LITER                                  NO2          = NITRITE
 CACO3        = CALCIUM CARBONATE                                     NO3          = NITRATE
 HCO3         = BICARBONATE                                           P            = PHOSPHORUS
 CO3          = CARBONATE                                             
 COLS./100 ML = COLONIES PER 100 MILLILITER                          
 %            = PERCENT                                              
 <            = LESS THAN



 Unless otherwise noted, all nutrients results are from filtered samples.

 *VALUE IS ESTIMATED BY USING A LOG-PROBABILITY REGRESSION
 #TO SEE COMPLETE NAME OF CONSTITUENTS, CLICK ON HIGHLIGHTED TEXT ABOVE