USGS Water-Year Summary 2023
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.
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.
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.
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.