05525000 DATA: Discharge Tables, 2000

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 1994-2000.

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 1999 TO SEPTEMBER 2000 DAILY MEAN VALUES
DAY	OCT	NOV	DEC	JAN	FEB	MAR	APR	MAY	JUN	JUL	AUG	SEP

1	45	31	27	61	e44	478	185	329	684	469	198	31
2	48	34	27	64	e45	384	178	411	727	418	159	30
3	43	35	27	69	e46	325	181	524	660	2460	133	29
4	41	35	29	82	e47	286	182	516	540	3550	127	28
5	41	36	37	80	e48	260	176	452	453	3150	112	28

6	46	36	48	92	e49	238	171	391	426	2680	97	28
7	47	36	75	70	e50	219	170	357	444	2130	90	29
8	43	37	92	63	e52	205	211	338	412	1570	91	29
9	38	37	82	59	e54	199	291	334	362	1030	99	28
10	34	37	68	74	e58	195	304	608	320	1320	102	28

11	31	35	60	77	66	183	279	927	288	2470	91	28
12	32	35	57	77	74	170	256	910	267	2660	76	46
13	31	35	55	79	83	162	232	755	273	2390	66	61
14	28	35	58	75	94	156	215	587	332	1930	60	66
15	27	34	69	62	100	154	212	475	623	1410	57	69

16	27	34	87	57	102	160	208	402	875	895	52	60
17	28	33	105	51	103	166	209	369	806	490	50	52
18	30	33	106	63	114	163	217	356	593	321	48	47
19	34	33	97	56	161	156	218	462	423	264	50	41
20	35	32	86	e53	233	186	311	487	351	247	52	37

21	32	32	e70	e49	276	316	1020	416	784	226	49	36
22	29	32	e58	e45	322	381	1310	368	1300	197	46	36
23	27	35	e51	e41	466	355	1300	346	1370	170	45	39
24	27	37	e47	e38	538	322	1160	326	1330	152	43	42
25	28	35	e44	e36	482	301	939	295	1470	138	41	43

26	28	34	e43	e36	396	280	694	264	1440	124	40	46
27	27	33	e43	e37	365	261	534	261	1280	111	40	45
28	26	31	e45	e38	533	253	443	423	1090	102	38	43
29	26	29	e48	e39	575	244	381	665	862	102	35	40
30	26	28	52	e40	---	224	342	721	628	138	33	37

31	27	---	56	e42	---	201	---	674	---	198	32	---

TOTAL	1032	1019	1849	1805	5576	7583	12529	14749	21413	33512	2252	1202
MEAN	33.3	34.0	59.6	58.2	192	245	418	476	714	1081	72.6	40.1
MAX	48	37	106	92	575	478	1310	927	1470	3550	198	69
MIN	26	28	27	36	44	154	170	261	267	102	32	28
CFSM	.05	.05	.09	.08	.28	.36	.61	.69	1.04	1.58	.11	.06
IN.	.06	.06	.10	.10	.30	.41	.68	.80	1.16	1.82	.12	.07

e Estimated

STATISTICS OF MONTHLY MEAN DATA FOR WATER YEARS 1945 - 2000, BY WATER YEAR (WY)
MEAN	246	341	535	638	797	1081	1093	849	735	432	140	186
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 1999 CALENDAR YEAR		FOR 2000 WATER YEAR		WATER YEARS 1945 - 2000
ANNUAL TOTAL	172366		104521
ANNUAL MEAN	472		286		588
HIGHEST ANNUAL MEAN					1323	1993
LOWEST ANNUAL MEAN					121	1964
HIGHEST DAILY MEAN	4810	Jan 26	3550	Jul 4	10200	Jun 14 1958
LOWEST DAILY MEAN	19	Sep 27	26	A	5.5	Sep 13 1964
ANNUAL SEVEN-DAY MINIMUM	21	Sep 22	27	Oct 24	6.6	Sep 8 1964
INSTANTANEOUS PEAK FLOW			3660	Jul 4	10400	Jun 13 1958
INSTANTANEOUS PEAK STAGE			18.58	Jul 4	26.31	Jun 13 1958
INSTANTANEOUS LOW FLOW			25	B	5.2	Sep 13 1964
ANNUAL RUNOFF (CFSM)	.69		.42		.86
ANNUAL RUNOFF (INCHES)	9.35		5.67		11.64
10 PERCENT EXCEEDS	1410		687		1600
50 PERCENT EXCEEDS	105		91		267
90 PERCENT EXCEEDS	28		32		32

A - Oct. 28-30.
B - Oct. 29-30.