05525000 DATA: Discharge Tables, 2001

Station list Available data
ILLINOIS RIVER BASIN

05525000 IROQUOIS RIVER AT IROQUOIS, IL

LOCATION.-- Lat 40°49'22", long 87°34'53", in NE1/4SE1/4 sec.15, T.27 N., R.11 W., Iroquois County, Hydrologic Unit 07120002, on left bank at upstream side of bridge on U.S. Highway 52 in Iroquois, 500 ft upstream from a railroad bridge, 4.5 mi downstream from Indiana-Illinois State line, and at mile 50.4.

DRAINAGE AREA.-- 686 mi².

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

DISCHARGE: October 1944 to current year.

STAGE: Water years 1994-2001.

SURFACE-WATER QUALITY

CHEMICAL: Water years 1978-91. Additional chemical data for water years 1972-77 are published in Water-Resources Investigations 78-23 and 79-24 as site FL 04.

SEDIMENT: October 1978 to September 1980, January 1993 to December 1995.

GAGE.-- Water-stage recorder, phone telemeter, rain gage, and crest-stage gage. Datum of gage is 614.34 ft above sea level. Prior to Aug. 5, 1945, nonrecording gage at same site and datum.

EXTREMES FOR PERIOD OF RECORD.--
SURFACE-WATER DISCHARGE AND STAGE: Maximum discharge, 10,400 ft³/s, June 13, 1958, gage height, 26.31 ft; minimum, 5.2 ft³/s, Sept. 13, 1964.
SUSPENDED-SEDIMENT CONCENTRATIONS: Maximum daily, 2,280 mg/L, June 2, 1980; minimum daily, 3 mg/L, Dec. 23, 24, 27-31, 1978.
SUSPENDED-SEDIMENT LOADS: Maximum daily, 12,200 tons, June 3, 1980; minimum daily, 0.45 ton, Dec. 28, 1978.

REMARKS FOR CURRENT YEAR.-- Records good except those for estimated daily discharges, which are poor.

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	36	44	108	e55	e800	3360	345	308	416	158	127	46
2	34	43	121	e57	e1100	2920	333	308	641	141	115	45
3	33	42	126	e60	e1050	2470	320	299	838	132	121	42
4	37	43	123	e64	e900	2010	309	279	879	229	123	38
5	42	42	115	e66	e750	1590	301	265	1920	757	101	36

6	49	42	e118	e68	e600	1210	309	257	4180	897	82	32
7	58	43	e120	e68	e500	910	367	254	4240	726	69	29
8	61	45	e110	e66	e700	695	435	250	3980	489	60	29
9	59	53	e100	e63	1870	581	424	240	3620	455	50	36
10	55	87	e90	e60	2880	520	588	230	3150	670	43	49

11	52	143	e100	e59	3150	484	1250	226	2640	631	40	71
12	49	161	e110	e60	3100	461	1820	219	2140	435	37	73
13	47	145	e110	e64	2870	461	1830	207	1660	288	37	65
14	46	141	e100	e70	2630	458	1650	197	1240	210	35	53
15	44	151	e95	e75	2540	444	1350	196	904	168	34	41

16	45	149	e85	e85	2370	441	1080	202	654	141	35	34
17	46	135	e75	e95	2110	482	893	207	505	122	34	30
18	47	119	e70	e105	1810	584	709	214	421	126	40	29
19	46	107	e66	e130	1480	639	582	224	371	232	49	32
20	46	100	e63	e125	1150	630	518	231	333	280	59	45

21	45	93	e60	e120	852	593	484	229	312	220	58	79
22	45	89	e57	e115	636	546	467	222	321	161	50	83
23	45	81	e54	e105	533	502	492	219	329	181	46	70
24	45	80	e51	e100	601	465	500	219	300	321	45	56
25	45	80	e48	e95	2420	431	462	225	265	457	69	47

26	47	84	e47	e92	3420	402	418	235	238	507	83	44
27	48	89	e46	e91	3660	381	387	317	218	674	75	42
28	48	94	e46	e90	3630	365	360	434	203	539	64	41
29	48	98	e48	e90	---	357	331	485	190	335	55	38
30	46	100	e50	e200	---	352	313	462	174	221	50	37

31	45	---	e52	e400	---	347	---	405	---	162	50	---

TOTAL	1439	2723	2564	2993	50112	26091	19627	8265	37282	11065	1936	1392
MEAN	46.4	90.8	82.7	96.5	1790	842	654	267	1243	357	62.5	46.4
MAX	61	161	126	400	3660	3360	1830	485	4240	897	127	83
MIN	33	42	46	55	500	347	301	196	174	122	34	29
CFSM	.07	.13	.12	.14	2.61	1.23	.95	.39	1.81	.52	.09	.07
IN.	.08	.15	.14	.16	2.72	1.41	1.06	.45	2.02	.60	.10	.08

e Estimated

STATISTICS OF MONTHLY MEAN DATA FOR WATER YEARS 1945 - 2001, BY WATER YEAR (WY)
MEAN	242	337	527	629	814	1077	1086	839	744	431	138	183
MAX	2556	1878	1794	3030	2213	3462	3116	1944	3496	1958	595	2020
(WY)	1994	1986	1968	1950	1950	1982	1950	1981	1958	1951	1990	1993
MIN	10.6	18.0	16.9	20.6	27.7	94.8	249	141	53.7	23.4	11.4	11.7
(WY)	1957	1957	1964	1945	1963	1957	1946	1958	1988	1988	1988	1964

SUMMARY STATISTICS	FOR 2000 CALENDAR YEAR		FOR 2001 WATER YEAR		WATER YEARS 1945 - 2001
ANNUAL TOTAL	107347		165489
ANNUAL MEAN	293		453		586
HIGHEST ANNUAL MEAN					1323	1993
LOWEST ANNUAL MEAN					121	1964
HIGHEST DAILY MEAN	3550	Jul 4	4240	Jun 7	10200	Jun 14 1958
LOWEST DAILY MEAN	28	A	29	Sep 7, 8, 18	5.5	Sep 13 1964
ANNUAL SEVEN-DAY MINIMUM	28	Sep 4	35	Sep 3	6.6	Sep 8 1964
MAXIMUM PEAK FLOW			4350	Jun 6	10400	Jun 13 1958
MAXIMUM PEAK STAGE			19.76	Jun 6	26.31	Jun 13 1958
INSTANTANEOUS LOW FLOW			28	Sep 18	5.2	Sep 13 1964
ANNUAL RUNOFF (CFSM)	.43		.66		.85
ANNUAL RUNOFF (INCHES)	5.82		8.97		11.60
10 PERCENT EXCEEDS	687		1170		1600
50 PERCENT EXCEEDS	110		143		264
90 PERCENT EXCEEDS	41		44		33

A - Sept. 4-6, 9-11.