05437500 DATA: Discharge Tables, 2003

Station list Available data
ROCK RIVER BASIN

05437500 ROCK RIVER AT ROCKTON, IL


LOCATION.-- Lat 42°26'55", long 89°04'11" (NAD of 1927), in SW1/4NE1/4 sec.24, T.46 N., R.1 E., Winnebago County, Hydrologic Unit 07090005, on right bank 750 ft downstream from State Highway 75 in Rockton, 1.0 mi downstream from Pecatonica River, and at mile 156.1.

DRAINAGE AREA.-- 6,363 mi².

PERIOD OF RECORD.--
SURFACE-WATER DISCHARGE AND STAGE
	DISCHARGE: June 1903 to July 1906, October 1906 to November 1907, January 1908 to March 1909, July 1914 to September 1919, October 1939 to current year. Published as "below mouth of Pecatonica River at Rockton" 1903-9; as "at Rockford" 1914-19. Monthly discharge only for some periods for 1903-1950, published in WSP 1308.
	STAGE: Water years 1994 to current year.
SURFACE-WATER QUALITY
	CHEMICAL: Water years 1978-91.

REVISED RECORDS.-- WSP 325: 1903-9. WSP 895: 1904(M). WSP 1508: 1915, 1916-17(M). WDR IL-75-1: Drainage area. WDR IL-97-1: 1996 (Dec. 10-23).

GAGE.-- Water-stage recorder, U.S. Army Corps of Engineers satellite telemeter and raingage, and crest-stage gage. Datum of gage is 707.94 ft above NGVD of 1929 (levels by U.S. Army Corps of Engineers). Prior to Oct. 1, 1906, nonrecording gage at site 800 ft upstream at datum about 1 ft higher. Oct. 1, 1906, to Mar. 31, 1909, nonrecording gage at site 800 ft upstream at datum about 2 ft higher. July 30, 1914, to Apr. 30, 1919, nonrecording gage at site at Rockford about 21 mi downstream, at different datum. Oct. 1, 1939, to Aug. 10, 1973, at site 800 ft upstream at same datum.

REMARKS.-- Low flow regulated by power-plant upstream from station.

EXTREMES FOR PERIOD OF RECORD.--
SURFACE-WATER DISCHARGE AND STAGE: Maximum discharge, 32,500 ft³/s, Mar. 30, 1916, gage height, 13.06 ft, site and datum then in use; minimum daily, 501 ft³/s, Sept. 14, 1958.

EXTREMES OUTSIDE PERIOD OF RECORD.--
SURFACE-WATER DISCHARGE AND STAGE: Flood in February 1937 reached a stage of 14.6 ft (backwater from ice), from floodmark.

REMARKS FOR CURRENT YEAR.-- Records good except those for 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	2800	3460	2880	e2800	2220	e2300	3400	3060	4810	2320	1850	e980
2	4020	3450	2910	e2700	2200	e2300	3340	3750	4430	2310	1870	e950
3	4120	3430	2820	e2600	e2400	e2300	3310	4620	4000	2320	1840	e990
4	4760	3320	2540	e2600	e2600	e2200	3250	5110	3920	2190	1970	922
5	5630	3450	2750	e2600	e2800	e2100	3290	5660	3930	2420	1950	900

6	5540	3320	2720	e2800	e2900	e2100	3260	5870	3440	2370	1810	876
7	5230	3010	2900	e2800	e2800	e2100	3220	5820	3410	2430	1850	834
8	5310	2780	3090	e2700	e2700	e2200	3310	5650	3280	2630	1930	741
9	5210	3110	2960	e2600	e2600	e2200	3150	6410	3240	3370	1910	894
10	4710	3320	2840	e2600	e2600	e2200	3070	7020	3430	3510	1840	855

11	4220	3280	3090	e2600	e2500	e2200	3160	7360	3180	3420	1780	870
12	3680	3260	2990	2590	e2500	e2200	3070	6960	2900	3050	1760	882
13	3520	3200	3070	e2500	e2500	e2200	3130	7060	3120	2930	1770	952
14	3470	3150	3090	e2500	e2600	2150	3090	7260	3000	2840	1780	1880
15	3440	3280	3090	e2500	e2700	e2300	2820	7700	3180	3500	1740	1860

16	3420	3300	3060	2710	e2700	e2400	2460	7930	3050	3440	1690	1470
17	3350	3210	3160	2780	e2600	e2500	2570	e7400	3170	2870	1550	1470
18	3410	3250	3200	2730	e2400	e2600	2340	e6800	3280	2780	1530	1990
19	3400	3210	3500	2740	e2400	e2800	1920	e6200	3380	2840	1480	1690
20	3330	3140	3490	2630	e2400	e3000	2430	e6200	3130	2500	1410	1170

21	3310	3220	3520	e2500	e2400	3020	2720	6860	2650	2350	e1400	1190
22	3390	3200	3500	e2400	e2400	3160	2800	6780	2550	2730	e1300	1390
23	3390	3090	3320	e2300	e2400	3140	2920	6590	2490	2520	e1100	1260
24	e3300	3140	3010	e2200	e2400	3060	3190	6360	2130	2450	e1070	990
25	e3200	3130	3010	e2100	e2400	3230	3330	5970	2060	2280	e1100	1200

26	3280	3070	3000	e2100	e2400	3510	3210	5660	2840	2110	e1000	1200
27	3250	2910	3010	e2100	e2400	3210	3320	5410	2140	1980	e1000	1000
28	3310	3100	e3000	e2100	e2300	3340	2990	5200	2350	1970	e970	1110
29	3560	3060	e3000	e2100	---	3440	2650	4890	2440	1950	e980	1230
30	3670	3110	e3000	e2100	---	3440	2610	4830	2370	1890	e1000	1070

31	3520	---	e2900	e2100	---	3500	---	5150	---	1880	e1000	---

TOTAL	119750	95960	94420	77180	70220	82400	89330	187540	93300	80150	47230	34816
MEAN	3863	3199	3046	2490	2508	2658	2978	6050	3110	2585	1524	1161
MAX	5630	3460	3520	2800	2900	3510	3400	7930	4810	3510	1970	1990
MIN	2800	2780	2540	2100	2200	2100	1920	3060	2060	1880	970	741
CFSM	0.61	0.50	0.48	0.39	0.39	0.42	0.47	0.95	0.49	0.41	0.24	0.18
IN.	0.70	0.56	0.55	0.45	0.41	0.48	0.52	1.10	0.55	0.47	0.28	0.20

e Estimated

STATISTICS OF MONTHLY MEAN DATA FOR WATER YEARS 1940 - 2003, BY WATER YEAR (WY)
MEAN	3139	3525	3286	3210	3879	7194	7299	5388	4555	3688	2886	2880
MAX	13340	11320	9049	9432	8365	13920	18530	17770	16960	17000	9039	7753
(WY)	1987	1986	1983	1960	1997	1974	1993	1973	2000	1993	1993	1972
MIN	857	1100	1004	800	1000	1692	2476	1103	1248	1056	793	780
(WY)	1965	1940	1959	1940	1940	1954	1958	1958	1977	1965	1958	1958

SUMMARY STATISTICS	FOR 2002 CALENDAR YEAR		FOR 2003 WATER YEAR		WATER YEARS 1940 - 2003
ANNUAL TOTAL	1703280		1072296
ANNUAL MEAN	4667		2938		4243
HIGHEST ANNUAL MEAN					9484	1993
LOWEST ANNUAL MEAN					1568	1958
HIGHEST DAILY MEAN	11800	Jun 9,10	7930	May 16	29700	Mar 25 1975
LOWEST DAILY MEAN	2140	Aug 11	741	Sep 8	501	Sep 14 1958
ANNUAL SEVEN-DAY MINIMUM	2270	Sep 13	850	Sep 6	622	Oct 2 1958
MAXIMUM PEAK FLOW			8000	May 16	30000	Mar 25 1975
MAXIMUM PEAK STAGE			6.26	May 16	15.54	Mar 25 1975
INSTANTANEOUS LOW FLOW			606	Sep 12
ANNUAL RUNOFF (CFSM)	0.73		0.46		0.67
ANNUAL RUNOFF (INCHES)	9.96		6.27		9.06
10 PERCENT EXCEEDS	7700		4660		8370
50 PERCENT EXCEEDS	3930		2820		3220
90 PERCENT EXCEEDS	2550		1450		1310