LOCATION.-- Lat 41°44'01", long 88°20'00", (NAD 1927) in NW1/4SE1/4 sec.33, T.38 N., R.8 E., Kane County, Hydrologic Unit 07120007, on left bank at dam 0.4 mi upstream from Mill Street bridge in Montgomery, 3.2 mi upstream from Waubansee Creek, and at mile 45.9.

DRAINAGE AREA.-- 1,732 mi².

PERIOD OF RECORD.--

SURFACE-WATER DISCHARGE AND STAGE

DISCHARGE: October 2002 to current year.

STAGE: October 2002 to current year.

MISCELLANEOUS MEASUREMENTS: Water year 1976.

SURFACE-WATER QUALITY

CHEMICAL: Water years 1978 to 1990. Additional chemical data for water years 1964, 1972-77 are published in Water-Resources Investigations 78-23 and 79-24 as site DT 38.

GAGE.-- Water-stage recorder, phone telemeter, and concrete dam. Datum of gage is 603.52 ft above NGVD of 1929.

REMARKS.-- Flow regulated by Algonquin Dam, 36 mi upstream from station; Stratton Lock and Dam (previously known as McHenry Dam), 52 mi upstream from station; and occasionally affected by wind action.

EXTREMES FOR PERIOD OF RECORD.--

SURFACE-WATER DISCHARGE AND STAGE: Maximum discharge, 8,800 ft³/s, May 31, 2004; gage height, 13.92 ft; minimum discharge, 123 ft³/s, Aug. 26, 2003, Sept. 8, 2003.