05525000 DATA: Discharge Tables, 1999

Station list Available data
ILLINOIS RIVER BASIN

05525000 IROQUOIS RIVER AT IROQUOIS, IL

LOCATION.--Lat 40°49'25", long 87°34'55", in NE1/4 SE1/4 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.--October 1944 to current year.

GAGE.--Water-stage recorder 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.

REMARKS.--Records good except those for estimated daily discharges, which are poor. Recording raingage and gage-height telemeter at station.

DISCHARGE, IN CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1998 TO SEPTEMBER 1999 DAILY MEAN VALUES
DAY	OCT	NOV	DEC	JAN	FEB	MAR	APR	MAY	JUN	JUL	AUG	SEP

1	45	62	70	e65	1970	1340	381	1930	315	359	61	36
2	44	61	76	e67	1610	1390	375	1760	405	593	54	33
3	46	57	86	e59	1360	1520	366	1520	562	693	51	32
4	50	58	87	e52	1170	1600	373	1250	580	625	47	31
5	60	66	84	e44	1020	1550	421	1020	511	463	44	32

6	62	66	82	e46	873	1660	447	847	435	332	43	28
7	62	59	81	e50	772	1780	422	718	376	255	43	25
8	77	55	86	e52	830	1750	386	624	335	212	42	24
9	99	53	103	e50	1150	1670	384	552	306	177	41	23
10	87	59	111	e49	1330	1480	396	501	284	150	47	22

11	70	72	103	e48	1370	1250	401	469	313	133	49	22
12	60	145	94	e47	1330	1040	439	455	336	118	52	23
13	52	176	87	e47	1210	880	463	527	444	105	139	24
14	48	145	83	e47	1060	774	447	708	625	94	180	23
15	46	120	81	e47	904	713	452	778	713	84	131	23

16	46	110	79	e52	775	755	1100	750	619	73	86	23
17	46	103	76	e62	697	1080	2300	668	463	71	62	23
18	47	95	75	e80	656	1240	2750	589	360	77	50	24
19	49	89	77	e120	611	1240	2830	515	305	75	44	25
20	51	82	78	e250	557	1140	2660	455	270	80	41	26

21	52	79	e80	e420	501	999	2360	414	244	105	41	26
22	49	77	e80	773	453	842	2050	409	224	184	41	24
23	47	74	e76	1790	423	702	1800	402	209	163	40	23
24	46	71	e73	3250	409	605	1680	402	198	115	39	22
25	44	70	e68	4320	390	540	1620	413	214	100	40	21

26	42	70	e63	4810	375	490	1560	388	265	103	43	20
27	42	70	e59	4580	594	455	1440	348	301	91	42	19
28	45	70	e58	4120	1150	435	1550	316	522	81	39	20
29	46	70	e60	3570	---	418	1910	296	519	77	37	24
30	55	70	e61	2990	---	396	2000	280	386	72	35	29

31	62	---	e63	2440	---	383	---	277	---	69	36	---

TOTAL	1677	2454	2440	34397	25550	32117	35763	20581	11639	5929	1740	750
MEAN	54.1	81.8	78.7	1110	912	1036	1192	664	388	191	56.1	25.0
MAX	99	176	111	4810	1970	1780	2830	1930	713	693	180	36
MIN	42	53	58	44	375	383	366	277	198	69	35	19
CFSM	.08	.12	.11	1.62	1.33	1.51	1.74	.97	.57	.28	.08	.04
IN.	.09	.13	.13	1.87	1.39	1.74	1.94	1.12	.63	.32	.09	.04

e Estimated

STATISTICS OF MONTHLY MEAN DATA FOR WATER YEARS 1945 - 1999, BY WATER YEAR (WY)
MEAN	250	347	544	649	808	1096	1106	856	735	420	141	188
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 1998 CALENDAR YEAR		FOR 1999 WATER YEAR		WATER YEARS 1945 - 1999
ANNUAL TOTAL	335885		175037
ANNUAL MEAN	920		480		593
HIGHEST ANNUAL MEAN					1323	1993
LOWEST ANNUAL MEAN					121	1964
HIGHEST DAILY MEAN	5680	Mar 22	4810	Jan 26	10200	Jun 14 1958
LOWEST DAILY MEAN	42	Oct 26, 27	19	Sep 27	5.5	Sep 13 1964
ANNUAL SEVEN-DAY MINIMUM	45	Oct 23	21	Sep 22	6.6	Sep 8 1964
INSTANTANEOUS PEAK FLOW			4890	Jan 26	10400	Jun 13 1958
INSTANTANEOUS PEAK STAGE			20.53	Jan 26	26.31	Jun 13 1958
INSTANTANEOUS LOW FLOW			19	Sep 27	5.2	Sep 13 1964
ANNUAL RUNOFF (CFSM)	1.34		.70		.86
ANNUAL RUNOFF (INCHES)	18.21		9.49		11.75
10 PERCENT EXCEEDS	2530		1410		1620
50 PERCENT EXCEEDS	415		120		270
90 PERCENT EXCEEDS	54		40		32