05586100 DATA: Discharge Tables, 2002

Station list Available data
ILLINOIS RIVER BASIN

05586100 ILLINOIS RIVER AT VALLEY CITY, IL


LOCATION.-- Lat 39°42'12", long 90°38'43" (NAD of 1927), 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 1994-2002.
SURFACE-WATER QUALITY
	CHEMICAL: Water years 1975-93 and 1996 to current.
	SEDIMENT: February 1980 to current year.
	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 NGVD of 1929 (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 fair except those for estimated daily discharges, which are poor.

DISCHARGE, in CFS, WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 DAILY MEAN VALUES
DAY	OCT	NOV	DEC	JAN	FEB	MAR	APR	MAY	JUN	JUL	AUG	SEP

1	10800	33600	14900	e14500	26100	34200	29900	54500	71700	34200	10200	14200
2	8980	33600	14800	e13800	27300	34200	29900	56200	69100	31800	8620	12000
3	7890	33800	15500	e13000	30100	33600	29700	57300	66300	29700	8460	10000
4	7450	33700	16900	e15000	32000	33400	29800	57400	62900	25900	8340	9830
5	7460	33100	16600	e14000	33500	33100	29800	56700	60100	22000	7300	9860

6	8430	32300	16200	e13500	34600	33400	29800	54900	57900	19400	8880	8520
7	9680	31400	16500	e13000	35300	33800	29800	51800	56500	17400	9210	7380
8	10400	30300	16600	e14000	35600	34500	30200	49600	54900	15300	8200	7180
9	10300	29100	16900	e12500	35700	34800	32400	50200	53200	13700	7310	6930
10	10200	27900	17200	e12000	35400	35800	34700	54100	51000	12900	8050	6190

11	8520	26800	17000	12900	35100	37800	36000	55800	49400	13000	7310	6250
12	10700	25500	16900	13800	34800	39400	36600	62200	48300	13400	7350	6700
13	12400	24000	16300	14200	34200	40800	37300	68900	52800	13800	7370	6480
14	14100	22600	15600	13700	33400	42000	38200	70900	56800	13800	7640	6380
15	16300	e18300	16200	12800	32300	43000	38800	81000	58200	13200	8240	6010

16	e21600	14200	16300	12900	31400	43600	39300	90800	60400	11500	8000	5950
17	24500	12100	17100	12600	30700	43800	39200	99400	62600	9830	9310	6130
18	25500	11100	18100	12000	29900	43800	39200	104000	64300	8630	10800	6330
19	26500	10000	e19400	12000	28900	43200	38500	105000	64500	7460	12700	6010
20	27400	9870	e22400	11900	28400	42500	38000	106000	63500	7310	13400	6200

21	27900	10500	24100	10600	28600	41400	37700	105000	60900	8430	12500	6190
22	28400	10100	25400	9730	29900	40200	39000	102000	57200	8660	12000	5290
23	29100	10200	26200	9850	31100	39100	40100	99600	54500	8720	15800	6170
24	30000	11800	26900	9830	32300	38100	41000	96400	51900	8500	23700	7440
25	30000	11200	27000	10900	33100	37000	42400	93300	49200	8530	26400	7680

26	30200	11900	26200	11300	33600	35600	43700	90200	46300	8310	28500	6260
27	30800	13600	e23200	10700	34100	34400	44100	87600	43900	10200	28800	4650
28	31800	13900	19800	9930	34400	33200	48800	84300	41100	12200	27800	5100
29	32500	14500	18300	10400	---	32300	51100	80500	38500	12500	26100	5600
30	32800	14300	17400	11400	---	31000	52800	77300	36200	12500	22000	5490

31	33400	---	e16000	e21500	---	30300	---	74300	---	11600	17800	---

TOTAL	616010	615270	587900	390240	901800	1153300	1127800	2377200	1664100	444380	418090	214400
MEAN	19870	20510	18960	12590	32210	37200	37590	76680	55470	14330	13490	7147
MAX	33400	33800	27000	21500	35700	43800	52800	106000	71700	34200	28800	14200
MIN	7450	9870	14800	9730	26100	30300	29700	49600	36200	7310	7300	4650

e Estimated

STATISTICS OF MONTHLY MEAN DATA FOR WATER YEARS 1939 - 2002, BY WATER YEAR (WY)
MEAN	12820	14430	17740	19640	24840	33850	37460	36870	30530	21490	13780	11370
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 2001 CALENDAR YEAR		FOR 2002 WATER YEAR		WATER YEARS 1939 - 2002
ANNUAL TOTAL	9254780		10510490
ANNUAL MEAN	25360		28800		22880
HIGHEST ANNUAL MEAN					46810	1993
LOWEST ANNUAL MEAN					8977	1940
HIGHEST DAILY MEAN	73300	Mar 4	106000	May 20	123000	May 27 1943
LOWEST DAILY MEAN	5950	Aug 19	4650	Sep 27	1330	Sep 2 1984
ANNUAL SEVEN-DAY MINIMUM	6540	Aug 15	6010	Sep 16	2290	Oct 8 1964
MAXIMUM PEAK FLOW			106000 A	May 19	123000 B	C
MAXIMUM PEAK STAGE			25.56 D	May 19	28.61 B	May 26 1943
INSTANTANEOUS LOW FLOW			4340	Sep 27
10 PERCENT EXCEEDS	51900		57000		48000
50 PERCENT EXCEEDS	19200		26200		16100
90 PERCENT EXCEEDS	8330		8030		6540

	A- Gage height, 25.52 ft.
	B- At Meredosia.
	C- May 26-28, 1943.
	D- Discharge, 105000 ft³/s.