05573540 DATA: Discharge Tables, 2004

Station list Available data
ILLINOIS RIVER BASIN


LOCATION.-- Lat 39°49'52", long 88°58'35" (NAD of 1927), in NE1/4NE1/4 sec.21, T.16 N., R.2 E., Macon County, Hydrologic Unit 07130006, on right upstream side of bridge on State Highway 48 in Decatur, 1.2 mi downstream from Lake Decatur Dam, 2.5 mi upstream from Stevens Creek, and at mile 129.0.

DRAINAGE AREA.-- 938 mi².

PERIOD OF RECORD.--
SURFACE-WATER DISCHARGE AND STAGE
	DISCHARGE: October 1982 to current year.
	STAGE: Water years 1994 to current year.
SURFACE-WATER QUALITY
	CHEMICAL: Water years 1979-91.

REVISED RECORDS.-- WDR IL-94-2: 1992

GAGE.-- Water-stage recorder, phone telemeter, and crest-stage gage. Datum of gage is 583.43 ft above NGVD of 1929.

REMARKS.-- Flow regulated by Lake Decatur Dam, 1.2 mi upstream.

EXTREMES FOR PERIOD OF RECORD.--
SURFACE-WATER DISCHARGE AND STAGE: Maximum discharge, 31,800 ft³/s, May 12, 2002, gage height, 24.33 ft; no flow in some years.

REMARKS FOR CURRENT YEAR.-- Records fair except those for Oct. 1-6, June 12 to July 1, July 12-23, and estimated daily discharges, which are poor.

Discharge, cubic feet per second, WATER YEAR OCTOBER 2003 TO SEPTEMBER 2004 DAILY MEAN VALUES
DAY	OCT	NOV	DEC	JAN	FEB	MAR	APR	MAY	JUN	JUL	AUG	SEP

1	12	22	954	1670	171	339	5780	590	1340	288	16	1060
2	10	25	807	1490	e165	311	4600	485	1270	411	16	546
3	8.8	25	702	1330	e155	286	3500	324	1590	453	14	248
4	8.3	26	582	1850	e140	441	3950	215	1770	398	14	110
5	9.2	35	557	3250	e130	1140	2960	47	2130	381	21	131

6	34	33	532	2210	e115	1740	1810	35	2740	232	18	129
7	120	32	499	1930	e100	1610	1730	337	1930	396	11	196
8	282	30	479	1930	e80	1720	1650	394	704	469	10	220
9	289	29	327	1470	e66	1380	1370	325	246	363	13	91
10	133	30	39	885	e50	1160	813	292	762	895	10	44

11	25	33	544	865	e34	1080	341	300	1390	1330	6.0	40
12	17	36	750	837	e20	871	827	283	1750	747	4.9	40
13	14	34	612	764	e45	726	708	384	2520	917	4.5	23
14	33	32	505	840	e80	635	499	2430	2030	750	4.5	15
15	13	30	457	815	e110	349	498	2890	4420	775	4.9	12

16	11	30	413	586	e135	55	505	2090	5960	784	5.7	12
17	9.6	33	417	767	154	26	497	1310	4520	668	6.2	11
18	9.0	742	418	741	179	26	435	1600	4200	567	8.4	13
19	8.4	1200	374	663	265	33	426	1840	3490	375	6.2	14
20	30	1830	352	394	376	85	462	2020	2760	204	18	13

21	20	1980	313	389	421	180	337	1930	1730	91	6.1	9.1
22	17	1680	303	557	417	455	666	1680	1350	71	4.8	6.8
23	14	1830	620	521	459	442	799	1370	1320	207	5.9	6.6
24	13	2260	963	487	498	309	693	969	826	251	16	6.1
25	16	2260	1150	477	497	386	596	1190	699	197	8.6	5.9

26	19	1990	1410	406	454	2700	559	1740	599	91	e200	5.7
27	18	1710	1410	257	366	4620	272	2030	607	27	e1800	5.7
28	19	1540	1110	174	317	5740	43	2040	599	16	2290	5.8
29	19	1390	740	170	315	6360	202	1960	556	8.0	2310	6.9
30	20	1150	110	172	---	6150	500	1890	372	14	1370	7.8

31	22	---	1310	172	---	6090	---	1760	---	9.7	1230	---

e Estimated

STATISTICS OF MONTHLY MEAN DATA FOR WATER YEARS 1983 - 2004, BY WATER YEAR (WY)
MEAN	213	529	739	624	899	1115	1078	1464	967	376	124	117
MAX	2217	4041	2294	3087	2803	2802	3674	4027	3131	1947	515	1736
(WY)	1994	1986	1991	1993	2001	1998	1994	1995	1998	1993	1985	1993
MIN	0.24	3.67	2.21	1.23	13.6	165	83.8	108	17.3	2.69	0.33	0.18
(WY)	1995	1983	1990	2003	2003	2000	1986	2001	1988	1989	1996	1998

SUMMARY STATISTICS	FOR 2003 CALENDAR YEAR		FOR 2004 WATER YEAR		WATER YEARS 1983 - 2004
ANNUAL TOTAL	126932.08		281769.1
ANNUAL MEAN	348		770		686
HIGHEST ANNUAL MEAN					1511	1993
LOWEST ANNUAL MEAN					164	2000
HIGHEST DAILY MEAN	2910	May 10	6360	Mar 29	19600	May 12 2002
LOWEST DAILY MEAN	0.10	A	4.5	Aug 13, 14	0.00	B
ANNUAL SEVEN-DAY MINIMUM	0.10	A	5.2	Aug 11	0.00	B
MAXIMUM PEAK FLOW			6740	Mar 28	31800 C	May 12 2002
MAXIMUM PEAK STAGE			15.82	Mar 28	24.33	May 12 2002
INSTANTANEOUS LOW FLOW			4.2	Aug 13, 23
10 PERCENT EXCEEDS	1150		1940		2000
50 PERCENT EXCEEDS	85		388		212
90 PERCENT EXCEEDS	0.46		11		1.5

	A - Estimated, several occurrences.
	B - At times in some years.
	C - From rating curve extended above 17,000 ft³/s.