Station list     Available data
ILLINOIS RIVER BASIN


05586100       ILLINOIS RIVER AT VALLEY CITY, IL



LOCATION.-- Lat 39°42'12", long 90°38'43", in SE1/4NW1/4 sec.34, T.15 N., R.14 W., Scott County, Hydrologic Unit 07130011, on upstream side of Norfolk & Southern Corporation Railroad bridge at Flints Creek, 0.4 mi east of Valley City, 1.8 mi downstream from Mauvaise Terre Creek, and at mile 61.3.

DRAINAGE AREA.-- 26,743 mi2, does not include diversion from Lake Michigan through the Chicago Sanitary and Ship Canal, which has occurred since Jan. 17, 1900.

PERIOD OF RECORD.--
SURFACE-WATER DISCHARGE AND STAGE
 

DISCHARGE: October 1938 to current year. Prior to October 1960, at site 0.2 mi upstream at same datum. Prior to October 1989, published as "at Meredosia." Records are considered equivalent.
 

STAGE: Water years 1994-2000.
SURFACE-WATER QUALITY
 

CHEMICAL: Water years 1975-93 and 1996 to current.
 

SEDIMENT: Water years 1980-99.
 

SPECIFIC CONDUCTANCE: Water years 1975-81.
 

WATER TEMPERATURE: Water years 1975-81.
 

MISCELLANEOUS: Contaminants in streambed sediments, October 1996; contaminants in fish tissue, October 1996.
BIOLOGICAL: Algae, water years 1980-81; Benthic macroinvertebrates, September 1997, September 1998; fish, August 1998.

GAGE.-- U.S. Army Corps of Engineers water-stage recorder, satellite telemeter and rain gage. Datum of gage is 418.00 ft above sea level (levels by U.S. Army Corps of Engineers).

REMARKS.-- Occasional regulation at low flow by navigation dam at La Grange. Since Jan. 17, 1900, flow has included diversion from Lake Michigan through Chicago Sanitary and Ship Canal. Suspended-sediment samples were collected by a local observer twice weekly with additional samples collected during high runoff periods. Since February 1994, samples used to compute sediment record have been collected at upstream side Rt. 106 bridge at Florence at mile 56.

EXTREMES FOR PERIOD OF RECORD.--
SURFACE-WATER DISCHARGE AND STAGE: Maximum discharge, 123,000 ft3/s, May 26-28, 1943; maximum gage height, 28.61 ft, May 26, 1943; minimum daily discharge, 1,330 ft3/s, Sept. 2, 1984.
SUSPENDED-SEDIMENT CONCENTRATIONS: Maximum daily, 3,720 mg/L, Apr. 14, 1981; minimum daily, 14 mg/L, Dec. 26, 1984, July 21, 1993.
SUSPENDED-SEDIMENT LOADS: Maximum daily, 410,000 tons, June 4, 1980; minimum daily, 172 tons, Sept. 2, 1984.

REMARKS FOR CURRENT YEAR.-- Records poor.
DISCHARGE, IN CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1999 TO SEPTEMBER 2000
DAILY MEAN VALUES
DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP
 
1 13200  5350  7340  6300  e4800  18000  9520  25600  21000  43000  11300  7180 
2 10700  4380  7170  7010  e4500  17400  8290  24700  e22300  42200  11300  6750 
3 9700  5760  6800  6070  e4500  17300  7640  23800  24200  41300  11800  6360 
4 9610  5840  5910  5750  e4700  16900  6650  e22000  25200  40100  13400  6310 
5 9890  5440  7000  6280  e5000  16500  8900  e21000  25500  41200  14000  6620 
 
6 9900  5490  10200  6670  e4700  15800  7240  19500  25800  42200  12600  7550 
7 9870  5480  11900  5890  e4700  14800  6440  16100  25900  42900  11000  7040 
8 8880  5110  10900  6150  e4800  12400  7120  13100  25700  42500  12800  6630 
9 5110  5390  9570  6480  e4800  9450  8290  12100  25200  41500  13900  7000 
10 5490  5440  9380  6370  e4800  8990  6910  13100  24600  40500  15100  7310 
 
11 6180  5150  10300  5510  5640  10800  6760  15600  24100  41100  15300  7830 
12 7220  5750  9700  6860  6830  12200  8160  16200  23900  41200  12900  7960 
13 7200  5470  7840  7940  6440  9640  9250  16100  23300  40900  11000  10300 
14 8080  5070  6510  8700  6150  7570  7610  16400  23000  40600  8720  12400 
15 7520  5270  6980  7610  7100  6980  6170  17400  23000  40200  6910  13600 
 
16 4980  5690  6540  5300  5620  7180  6790  17800  23300  40000  6600  14700 
17 4760  5840  6720  6240  6590  9770  7770  17800  24100  39600  8690  14400 
18 5210  6840  7040  5860  7550  11500  10000  18200  24600  38600  8170  13400 
19 5530  5890  7600  5610  7110  8710  11400  17700  25100  37400  8230  12300 
20 5360  5230  6330  4850  7780  8580  12100  17300  25700  36600  8200  11000 
 
21 5630  6420  4950  5500  7850  9920  12800  17700  27900  35400  8320  10800 
22 4730  5960  5500  6230  7380  10500  18200  18100  29900  33400  6440  11900 
23 4910  5720  5840  4990  7410  11000  e20000  18300  32300  31500  6100  10400 
24 5380  5400  5610  5210  7750  11000  23300  21100  33600  29300  8490  10800 
25 5760  6370  e5400  4630  9620  9910  24200  23000  35700  26800  9260  12600 
 
26 5280  5630  e5370  5480  13500  9400  25600  e21500  38800  22700  8400  13700 
27 5800  6030  5350  e4800  14800  9260  26500  22000  39900  18400  7090  14200 
28 5350  6480  5390  e4600  17300  8580  26800  22400  40800  15200  7180  13100 
29 5960  7350  5610  e4400  18900  10300  26800  e22600  41900  13000  6250  13000 
30 5720  6270  5950  e4500  ---  11000  26400  e21900  42900  11400  5970  12500 
 
31 5780  ---  6240  e4700  ---  10500  ---  e21200  ---  11300  6960  --- 

TOTAL 214690 171510 222940 182490 218620 351840 393610 591300 849200 1062000 302380 309640
MEAN 6925 5717 7192 5887 7539 11350 13120 19070 28310 34260 9754 10320
MAX 13200 7350 11900 8700 18900 18000 26800 25600 42900 43000 15300 14700
MIN 4730 4380 4950 4400 4500 6980 6170 12100 21000 11300 5970 6310

e Estimated
STATISTICS OF MONTHLY MEAN DATA FOR WATER YEARS 1939 - 2000, BY WATER YEAR (WY)
MEAN 12730 14330 17860 19890 24280 33460 37560 36480 29940 21750 13830 11450
MAX 54840 48900 78130 59540 67060 94940 93800 78160 87690 60820 50850 62870
(WY) 1994 1986 1983 1993 1974 1985 1979 1970 1974 1993 1981 1993
MIN 4258 5519 5923 4808 4144 10870 10010 11170 6207 6649 5709 5164
(WY) 1965 1957 1963 1963 1963 1964 1956 1988 1988 1988 1941 1976

SUMMARY STATISTICS FOR 1999 CALENDAR YEAR FOR 2000 WATER YEAR WATER YEARS 1939 - 2000
ANNUAL TOTAL 8474960  4870220         
ANNUAL MEAN 23220  13310          22780         
HIGHEST ANNUAL MEAN 46810          1993
LOWEST ANNUAL MEAN 8977          1940
HIGHEST DAILY MEAN 61500      Feb 4 43000              Jul 1 123000          May 27 1943
LOWEST DAILY MEAN 4380      Nov 2 4380              Nov 2 1330          Sep 2 1984
ANNUAL SEVEN-DAY MINIMUM 5160      Oct 17 4570              Jan 28 2290          Oct 8 1964
INSTANTANEOUS PEAK FLOW 43800      A     Jun 30 123000      B C
INSTANTANEOUS PEAK STAGE 12.86 D     Jun 29 28.61 B May 26 1943
INSTANTANEOUS LOW FLOW 4060              Oct 22
10 PERCENT EXCEEDS 52700  26800          47700         
50 PERCENT EXCEEDS 11900  8940          16100         
90 PERCENT EXCEEDS 5450  5350          6500         
A - Gage height, 12.74 ft.
B - At meredosia.
 C - May 26-28, 1943.
 D - Discharge, 41,300 ft3/s.


Table of Contents

Introduction

Station Descriptions

Surface-Water Data

Ground-Water Data

Meteorological Data

Biological Data