Station list     Available data
ROCK RIVER BASIN


05437500       ROCK RIVER AT ROCKTON, IL



LOCATION.-- Lat 42°26'55", long 89°04'11", 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 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 1994-2000.

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 sea level (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 fair 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
DAYOCTNOVDECJANFEBMARAPRMAYJUNJULAUGSEP
 
14550 2960 2800 e2400 e2200 8920 3770 4750 14000 8440 4850 3350 
24370 2920 2720 e2500 e2100 8820 3710 4560 18200 8110 4670 3320 
34240 2920 2980 e2600 e2050 8450 3700 4410 19900 10100 4530 3300 
44230 2880 3160 e2650 e2000 7610 3550 4360 20600 9620 4450 3280 
54100 2860 3660 e2700 e2050 6930 3460 4050 20900 9240 4360 3270 
 
63950 2740 3710 2740 e2100 6490 3570 4050 20800 8960 4870 3160 
74010 2520 3620 2920 e2300 6260 3690 3910 20400 8650 4720 3080 
83880 2550 3660 2880 2560 6100 3440 3820 20200 8170 5120 3040 
93530 2930 3670 2890 2630 5900 3250 4100 20000 7790 5430 2990 
103460 2870 3760 2990 2660 5870 3270 4590 19600 8450 5230 3000 
 
113370 2910 3700 3110 2680 5730 3360 4810 18800 8840 5130 3100 
123260 2880 3720 3220 2650 5560 3210 4860 19400 8430 4620 4630 
133250 2860 3640 3230 2600 5380 2970 4660 21500 8270 4270 5320 
143300 2900 3880 2930 2610 5270 3000 4400 22200 8010 4170 5480 
153130 2970 3990 2900 2600 5280 2980 4240 22000 7610 4050 5700 
 
163490 3050 3860 3100 2580 5260 3130 4450 21400 7150 3940 5400 
173450 2930 3770 3120 2590 5200 3190 4450 20200 6760 3830 4910 
183480 2510 3440 3050 2600 4920 3070 5200 18900 6410 3720 4490 
193510 2510 3340 3070 2620 4700 3250 7900 17500 6190 3710 4190 
203400 2310 3150 2840 2730 4660 4770 9430 16200 5980 3750 3870 
 
213300 2570 2570 2800 2760 4570 7110 9980 14900 5770 3760 3750 
223290 2580 e2600 3100 2830 4550 6750 10600 13600 5420 3690 4080 
233200 2700 e2500 e2900 3500 4480 6700 10900 12900 5180 3650 6150 
243170 2790 e2400 e2800 5150 4590 6570 10900 12300 4990 3660 7110 
253100 2910 e2300 e2700 6470 4540 6560 10100 11800 4910 3600 6930 
 
263070 2960 e2250 e2600 7480 4290 6140 9770 11200 4510 3560 6990 
273050 2980 e2200 e2500 8150 4280 5570 9820 10600 4230 3560 6100 
283040 2970 e2200 e2450 8440 4190 5210 10200 10100 4350 3490 5290 
293010 2930 e2200 e2400 8770 4140 5120 10200 9570 4230 3310 4750 
302990 2890 e2300 e2300 --- 4110 4840 9850 9020 4210 3430 4400 
 
313000 --- e2350 e2250 --- 3970 --- 10100 --- 4310 3400 --- 

TOTAL108180842609610086640102460171020128910209420508690213290128530134430
MEAN3490280931002795353355174297675516960688041464481
MAX455030503990323087708920711010900222001010054307110
MIN299023102200225020003970297038209020421033102990
CFSM.55.44.49.44.56.87.681.062.661.08.65.70
IN..63.49.56.51.601.00.751.222.971.25.75.79

e Estimated
STATISTICS OF MONTHLY MEAN DATA FOR WATER YEARS 1940 - 2000, BY WATER YEAR (WY)
MEAN308134913262321038447256734453314469370128842870
MAX1334011320904994328365139201853017770169601700090397753
(WY)198719861983196019971974199319732000199319931972
MIN85711001004800100016922476110312481056793780
(WY)196519401959194019401954195819581977196519581958

SUMMARY STATISTICSFOR 1999 CALENDAR YEARFOR 2000 WATER YEARWATER YEARS 1940 - 2000
ANNUAL TOTAL2067230         1971930         
ANNUAL MEAN5664         5388         4228     
HIGHEST ANNUAL MEAN9484     1993
LOWEST ANNUAL MEAN1568     1958
HIGHEST DAILY MEAN15600             Apr 2922200             Jun 1429700     Mar 25 1975
LOWEST DAILY MEAN1900      A    Jan 17-192000      A    Feb 4501     Sep 14 1958
ANNUAL SEVEN-DAY MINIMUM1970      A    Jan 132110      A    Jan 31622     Oct 2 1958
INSTANTANEOUS PEAK FLOW22500             Jun 1430000     Mar 25 1975
INSTANTANEOUS PEAK STAGE12.66        Jun 1415.54Mar 25 1975
INSTANTANEOUS LOW FLOW1860             Nov 18
ANNUAL RUNOFF (CFSM).89    .85    .66
ANNUAL RUNOFF (INCHES)12.09    11.53    9.03
10 PERCENT EXCEEDS10400         10000         8400     
50 PERCENT EXCEEDS4910         3860         3180     
90 PERCENT EXCEEDS2500         2600         1300     
A - Estimated due to backwater from ice.

Table of Contents

Introduction

Station Descriptions

Surface-Water Data

Ground-Water Data

Meteorological Data

Biological Data