Station list
05443500 ROCK RIVER AT COMO, IL
LOCATION.--Lat 41�47'00", long 89�44'58", in NE¼NE¼ sec.25, T.21 N., R.6 E., Whiteside County, Hydrologic Unit
07090005, on left bank, 1 mi upstream from Como, 3 mi downstream from Rock Falls, 3.5 mi upstream from Elkhorn Creek, and
at mile 69.2.
DRAINAGE AREA.--8,753 mi2.
PERIOD OF RECORD.--March to December 1905, October 1914 to September 1971, water years 1972-77 (annual maximums),
October 1977 to September 1986. Water years 1987-90, seven-month period (March to September). October 1990 to current
year. Published as "at Sterling" 1905-6 and as "at Lyndon" 1914-34. Records published for both sites December 1933 to
September 1934. Monthly discharge only for some periods, published in WSP 1308.
REVISED RECORDS.--WSP 1308: 1915(M), 1917-18(M), 1922(M), 1924(M), 1926(M), 1928(M), 1931-32(M),
1934(M). WDR IL-79-1: Drainage area. WDR IL-97-l: 1996 (Dec. 12-23).
GAGE.--Water-stage recorder and crest-stage gage. Datum of gage is 606.83 ft above sea level. Jan. 6, 1905, to Feb. 17, 1906,
nonrecording gage at Sterling, 3 mi upstream, at different datum. Nov. 24, 1914, to Sept. 30, 1934, nonrecording gage at Lyndon,
16.5 mi downstream at datum 22.46 ft lower.
REMARKS.--Records good except those for Nov. 17-21, which are fair, and those for estimated daily discharges , which are poor.
Some diurnal fluctuation caused by powerplants upstream from station. Gage-height telemeter at station.
EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 59,700 ft3/s, Apr. 21, 1973, gage height, 15.66 ft, from rating
curve extended above 41,200 ft3/s; maximum gage height, 17.51 ft, Feb. 7, 1938, backwater from ice; minimum daily discharge,
440 ft3/s (498 ft3/s, site then in use), Aug. 20, 1934.