USGS Water-Year Summary 2024

05590800 LAKE FORK AT ATWOOD, IL

LOCATION - Lat 39°48'22.7", long 88°28'34.4" referenced to North American Datum of 1983, in NE 1/4 NW 1/4 sec.36, T.16 N., R.6 E., Piatt County, IL, Hydrologic Unit 07140201, on left bank at downstream side of bridge, 0.9 mi northwest of Atwood and at mile 9.0.

DRAINAGE AREA - 149 mi².

REVISIONS HISTORY -

WDR IL-93-1: 1989(M), 1990-92. WDR IL-94-1: 1989.

On May 22, 2020, discharge for Jan. 4, 2017, was revised due to a database error.

Revisions: Gage datum was updated to 643.99 ft NAVD88 on June 6, 2023, as determined by a GNSS Level II survey. Gage datum was previously published as 644.58 ft NGVD29 (644.35 ft NAVD88) from levels.

Small sections of discharge from June 26, to October 23, 2023 were revised to keep estimated discharge lower than original raw data due to a backwater affect from beaver dams.

SURFACE-WATER RECORDS

PERIOD OF RECORD -
SURFACE-WATER DISCHARGE AND STAGE
  DISCHARGE: October 1972 to current.
  STAGE: Water years 1994 to current.

GAGE - Water-stage recorder, satellite telemeter, and crest-stage gage. Datum of gage is 643.99 ft above North American Vertical Datum of 1988. 

REMARKS - Diurnal fluctuations occur during low-flow periods due to effluent from the Bement Sanitary plant 10 mi. upstream. Accuracy of records is discussed in the annual Station Analysis archived at the USGS IL Water Science Center.

EXTREMES FOR PERIOD OF RECORD -
SURFACE-WATER DISCHARGE AND STAGE: Maximum discharge, 4,120 ft³/s, Dec. 29, 2015, gage height, 15.82 ft; no flow for many days in most years.