05586100 DATA: Discharge Tables, 2001

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 1995-2001.

SURFACE-WATER QUALITY

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

SEDIMENT: Water years 1980 to current.

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: Water years 1997-98.

FISH: Water year 1998.

HABITAT: Water years 1997 and 1998.

GAGE.-- U.S. Army Corps of Engineer's water-stage recorder, satellite telemeter and rain gage, crest-stage gage, and water-quality monitor. 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.

EXTREMES FOR CURRENT YEAR.--
SUSPENDED-SEDIMENT CONCENTRATIONS: Maximum daily, 1,300 mg/L, June 6; minimum daily, 36 mg/L, May 16.
SUSPENDED-SEDIMENT LOADS: Maximum daily, 140,000 tons, June 6; minimum daily, 925 tons, Nov. 1.

DISCHARGE, IN CUBIC FEET PER SECOND, WATER YEAR OCTOBER 2000 TO SEPTEMBER 2001 DAILY MEAN VALUES
DAY	OCT	NOV	DEC	JAN	FEB	MAR	APR	MAY	JUN	JUL	AUG	SEP

1	11300	8910	13600	e7100	32400	70200	36900	25500	27500	21300	11200	10700
2	10100	8200	13300	e7100	37500	72500	35500	23400	28600	19800	9860	10600
3	9090	7450	13500	e7100	39800	73000	34200	20600	29300	17200	9920	10600
4	11200	8280	12900	e7100	41000	73300	32600	18900	e31000	15800	10800	9530
5	13700	9120	11000	e7000	41000	72500	31200	18600	e34000	15000	12200	9860

6	14000	10700	11000	e7000	41100	71100	29600	e18200	e40000	16200	12900	10200
7	14500	9650	10700	e7000	40500	69300	27700	e18000	e46000	16300	12100	8430
8	14600	9230	9790	e6900	39800	66800	24900	e17600	e49000	15500	10200	7010
9	14400	11200	10200	e6900	42600	63800	21900	e17200	e51000	14900	9370	7400
10	14100	14600	10200	e6800	45200	61100	23800	e17200	e52000	14800	8220	8860

11	13100	17500	10600	e6900	47100	58600	28100	e17600	e53000	14700	8320	9820
12	13500	18900	9880	e7100	50200	56400	32000	e17800	e54000	14300	8290	10200
13	12700	19900	e9500	e7300	53500	54000	34000	e18000	e54000	13900	8330	9810
14	11300	20100	e8500	e7600	57500	51900	35500	e18300	54100	12900	7870	9700
15	11300	20500	e7000	e8200	60600	50400	36300	e19000	53500	11900	6920	9720

16	12000	20500	e6200	e9000	62600	49900	36000	e19800	52600	10200	6720	9020
17	11700	20100	e7200	e10000	62900	50200	35600	e21000	51800	8600	6230	7560
18	11200	20300	e7500	e11400	63200	49600	35200	e22600	49900	8880	6360	6910
19	9810	20000	e7400	e12500	62900	48600	34400	e24500	47600	8910	5950	8080
20	9440	18500	e7000	e14000	61900	48300	33700	e26500	45400	9530	6160	8270

21	8900	17800	e6400	e15200	60800	48200	32800	e28000	43900	8860	7460	12500
22	8930	16500	e7200	e17600	59500	47900	31900	e27500	42300	8620	7090	13800
23	9560	14700	e8000	e17000	57900	47500	32000	e26500	40700	8480	14700	14200
24	9700	12400	e8800	16500	57000	46800	31200	e25500	38600	8360	19200	14600
25	9310	12300	e9600	13200	59400	45700	30500	e24000	36500	9210	18000	15700

26	8720	12800	e9500	12600	61200	44500	29400	21700	34400	11400	17000	15800
27	9020	12200	e9200	10300	63200	43200	28900	21200	32400	13400	16900	15300
28	9440	12100	e8300	10500	66600	42000	28100	21300	30400	14100	15600	14100
29	10500	11900	e7700	16900	---	40700	27200	21700	28900	13000	13900	12800
30	10500	12600	e7400	28700	---	39500	26700	23500	24900	12000	13900	11600

31	10200	---	e7200	29000	---	38400	---	25800	---	11800	13000	---

TOTAL	347820	428940	286270	351500	1468900	1695900	937800	667000	1257300	399850	334670	322680
MEAN	11220	14300	9235	11340	52460	54710	31260	21520	41910	12900	10800	10760
MAX	14600	20500	13600	29000	66600	73300	36900	28000	54100	21300	19200	15800
MIN	8720	7450	6200	6800	32400	38400	21900	17200	24900	8360	5950	6910

e Estimated

STATISTICS OF MONTHLY MEAN DATA FOR WATER YEARS 1939 - 2001, BY WATER YEAR (WY)
MEAN	12710	14330	17730	19750	24730	33800	37460	36240	30130	21600	13780	11440
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 2000 CALENDAR YEAR		FOR 2001 WATER YEAR		WATER YEARS 1939 - 2001
ANNUAL TOTAL	5324110		8498630
ANNUAL MEAN	14550		23280		22790
HIGHEST ANNUAL MEAN					46810	1993
LOWEST ANNUAL MEAN					8977	1940
HIGHEST DAILY MEAN	43000	Jul 1	73300	Mar 4	123000	May 27 1943
LOWEST DAILY MEAN	4400 A	Jan 29	5950	Aug 19	1330	Sep 2 1984
ANNUAL SEVEN-DAY MINIMUM	4570	Jan 28	6540	Aug 15	2290	Oct 8 1964
MAXIMUM PEAK FLOW			74600 B	Mar 4	123000 C	D
MAXIMUM PEAK STAGE			18.49 E	Mar 2	28.61 C	May 26 1943
INSTANTANEOUS LOW FLOW			5710	Aug 19
10 PERCENT EXCEEDS	26800		51900		47900
50 PERCENT EXCEEDS	11200		15300		16100
90 PERCENT EXCEEDS	6220		7580		6520

	A- Estimated due to backwater from ice.
	B- Gage height, 18.33 ft.
	C- At Meredosia .
	D- May 26-28, 1943.
	E- Discharge, 72,300 ft³/s.