USGS Water-Year Summary 2024
421120088281801 HUNT-09-03
Sand and gravel aquifers (glaciated regions)
Quaternary System
LOCATION - Lat 42°11'19.94", long 88°28'18.14" referenced to North American Datum of 1983, in NW 1/4 NW 1/4 SW 1/4 sec.19, T.43 N., R.7 E., McHenry County, IL, Hydrologic Unit 07090006, 144 feet east of northern-most building at end of Diekman Road in McHenry County Henming Parcel Conservation Area, 0.3 miles west of South Branch Kishwaukee River, 0.4 miles northeast of County Highway 12 (Harmony/Huntley Road), 2.7 miles northwest of Huntley. Owner: Illinois State Geological Survey.
REVISIONS HISTORY - Revisions: Land-surface datum was updated to 881.12 ft NAVD88 on May 30, 2023, as determined by a GNSS Level II survey. Land-surface datum was previously published as 878 ft NAVD88 from LiDAR. Discrete water-level measurements prior to May 30, 2023, are referenced to the original datum.
GROUNDWATER RECORDS
WELL CHARACTERISTICS - Depth 150.7 ft. Upper casing diameter undefined; top of first opening 145.4 ft, bottom of last opening 150.4 ft. Well-casing includes 2-inch schedule 40 PVC pipe, 5.5 in. diameter borehole sealed with benseal grout, observation well.
DATUM - Land-surface datum is 881.12 ft above North American Vertical Datum of 1988. Measuring point: unknown, 3.0 ft above land-surface datum, Sep. 11, 2009 to present; unknown, 881.0 ft above land-surface datum, Sep. 11, 2009 to present.
PERIOD OF RECORD -
GROUND-WATER LEVELS: September 2009 to current. Prior to September 2009,
observation well readings available from the Illinois State Geological Survey.
GROUND-WATER QUALITY:
CHEMICAL: Water year 2011.
GAGE - Water level recorder and satellite telemeter.
EXTREMES FOR PERIOD OF RECORD - Highest water level, 21.46 ft below land-surface datum, May 25, 2020; lowest, 31.92 ft below land-surface datum, November 14, 2012.