LIRB Pages
Home
LIRB NAWQA
Basin Information
Ground Water
Surface Water
Bed Sediment & Fish
   Tissue
    Site Descriptions
       Blyton
       Colmar
       Decatur
       Easton
       El Paso
       Glenarm
       Green Valley
       Greenview
       Hardin
       Havana
       Henry
       Kingston Mines
       Leonore
       Lincoln
       Marseilles
       Monticello
       Niantic
       Oakford
       Valley City
       Wyoming
Ecology
Maps
Illustrations
Survey Data
Aerial Photography
Publications
Staff
Data Retrieval
Glossary

 Parent Pages
USGS Home
NAWQA Home
Illinois Water Science Center Home

QUADRANGLE: Petersburg, 15' series

LOCATION: Lat 40 41'46", long 89 51'40", in NE1/4NW1/4 sec. 26, T.21 N., R.7 W., on right bank at downstream side of highway bridge, 0.1 mile downstream from confluence of Hardin and Central ditches, 1.2 miles upstream from Samuels ditch, and 1.2 miles northwest of Easton.

ESTABLISHMENT: Wire-weight gage installed Oct. 25, 1949; graphic water-stage recorder installed Mar. 30, 1950; digital water-stage recorder installed Apr. 19, 1966.

DRAINAGE AREA: 28.7 sq. mi.

GAGE: Digital water-stage recorder in 48" corrugated steel shelter. Inside gage is a graduated tape by which a float operates the gage. Outside gage is a Type-A wire-weight gage attached to downsteam handrail of bridge. Correct check bar reading is 14.64 ft., gage datum.

GAGE DATUM: Datum of gage is 486.78 ft above MSL, datum of 1929. On July 1, 1958, Herreid and Hood ran levels to R.M. #1 from a bench mark: A chiseled square on north end of east headwall of concrete culvert (USGS BM in Bull. 930-C, page 805) elevation 504.53 ft above MSL. datum of 1929. R.M. #1 was found to be 5.458 ft lower than starting B.M. (closed loop 2.5 miles with error of closure of 0.006 ft).

CHANNEL: The bed of the stream is composed of very fine sand and clay. The channel has been deepened and straightened for about 5 miles below the gage.

DISCHARGE MEASUREMENTS: Wading measurements may be made at the bridge up to about 3.5 ft gage height. The bottom is soft mud and velocity is medium. Handline measurements can be made from the bridge. The upstream and downstream handrails are both marked off in 2-ft increments starting with zero at the left abutment.

FLOODS: Sept. 20. 1955, maximum discharge, 500 cfs Mar. 4, 1963; maximum gage height, 9.09 ft Feb. 10, 1959.

WINTER FLOW: There will be backwater from ice during winter periods.

REGULATION AND DIVERSION: None known.