05573540 DATA: Discharge Tables, 2003

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 Aug. 19 to Sept. 30, and estimated daily discharges, which are poor.

Discharge, cubic feet per second, WATER YEAR OCTOBER 2002 TO SEPTEMBER 2003 DAILY MEAN VALUES
DAY	OCT	NOV	DEC	JAN	FEB	MAR	APR	MAY	JUN	JUL	AUG	SEP

1	e0.10	4.6	16	2.9	e0.45	e48	127	e0.10	254	260	143	495
2	e0.10	4.6	27	2.6	e0.50	e44	2.0	0.49	327	14	201	1120
3	0.35	5.0	35	2.6	e0.56	e22	e0.10	2.7	350	e0.10	184	1270
4	5.7	5.6	28	2.4	e0.60	3.4	31	159	196	e0.10	172	1150
5	e0.10	9.6	26	2.6	e0.45	21	85	640	148	e0.10	225	690

6	0.38	9.5	24	2.4	0.35	49	89	796	167	e0.10	368	347
7	0.59	9.3	22	2.3	e0.10	53	49	995	175	e0.10	474	331
8	0.76	9.7	18	2.0	e0.10	52	0.43	867	139	32	318	274
9	0.79	11	15	2.0	e0.10	48	471	716	142	401	271	217
10	1.1	14	15	1.6	e0.10	45	662	2910	143	1190	236	122

11	1.4	16	15	1.3	e0.10	45	560	2210	215	1270	62	55
12	1.6	17	14	1.2	e0.10	74	450	1440	1330	1240	11	54
13	1.5	17	14	1.2	e0.10	237	386	1610	1790	1440	3.9	51
14	1.9	18	14	1.1	e0.46	257	169	1300	2870	2090	3.7	50
15	1.9	19	14	e1.0	e0.44	16	19	1600	2570	2270	3.7	41

16	1.8	18	14	e0.94	e0.41	239	104	1230	1680	2150	3.8	33
17	1.8	18	15	e0.86	e0.38	517	301	954	1690	1080	3.1	28
18	11	18	67	e0.80	e0.37	183	284	876	1070	515	3.1	27
19	16	20	42	e0.74	e0.38	504	208	613	1160	542	3.7	26
20	3.3	20	14	e0.68	e0.42	619	194	610	748	525	3.9	24

21	1.4	24	6.1	e0.63	e0.47	618	85	717	472	908	3.9	23
22	0.89	25	3.9	e0.58	e0.60	597	1.5	493	440	855	3.8	22
23	11	23	2.4	e0.53	e40	324	0.34	362	276	702	3.5	19
24	10	21	2.2	e0.49	e86	7.5	21	282	220	479	3.7	18
25	8.1	21	2.3	e0.45	e76	e0.10	194	229	180	331	3.9	15

26	3.2	19	1.8	e0.40	e62	e0.10	202	255	347	175	4.1	25
27	2.0	19	1.5	e0.35	e57	e0.10	144	362	454	168	4.2	22
28	2.4	18	1.6	e0.33	e53	96	131	298	275	168	3.7	18
29	9.0	19	2.1	e0.32	---	463	58	278	220	166	18	15
30	4.3	18	3.5	e0.36	---	486	0.42	181	429	165	3.7	15

31	4.3	---	3.3	e0.40	---	370	---	179	---	164	50	---

e Estimated

STATISTICS OF MONTHLY MEAN DATA FOR WATER YEARS 1983 - 2003, BY WATER YEAR (WY)
MEAN	221	520	744	609	932	1095	1069	1477	924	375	116	118
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 2002 CALENDAR YEAR		FOR 2003 WATER YEAR		WATER YEARS 1983 - 2003
ANNUAL TOTAL	298868.91		84882.14
ANNUAL MEAN	819		233		682
HIGHEST ANNUAL MEAN					1511	1993
LOWEST ANNUAL MEAN					164	2000
HIGHEST DAILY MEAN	19600	May 12	2910	May 10	19600	May 12 2002
LOWEST DAILY MEAN	0.10	A	0.10	A	0.00	B
ANNUAL SEVEN-DAY MINIMUM	0.10	A	0.10	A	0.00	B
MAXIMUM PEAK FLOW			5940	May 10	31800 C	May 12 2002
MAXIMUM PEAK STAGE			16.34	May 10	24.33	May 12 2002
INSTANTANEOUS LOW FLOW				D
10 PERCENT EXCEEDS	2630		708		2010
50 PERCENT EXCEEDS	136		21		205
90 PERCENT EXCEEDS	0.24		0.43		1.4

	A - Estimated, many days.
	B - Many days in some years.
	C - From rating curve extended above 17,000 ft³/s.
	D - Minimum unknown.