USGS Water-Year Summary 2024
422142088303102 7-HRT-I
Sand and gravel aquifers (glaciated regions)
Quaternary System
LOCATION - Lat 42°21'42.2", long 88°30'31.5" referenced to North American Datum of 1983, in SW 1/4 NW 1/4 SW 1/4 sec.23, T.45 N., R.6 E., McHenry County, IL, Hydrologic Unit 07120006, 20 feet northeast of northeast corner of Valley Hi Nursing Home parking lot, 0.1 mi. east of County Highway 26 (Hartland Road), 0.1 mi. south of Nelson Road, 0.15 mi. southwest of Hartland, 140 ft. southeast of detention basin for Valley Hi Nursing Home, 0.6 mi. west of tributary to Nippersink Creek and 1.9 mi. east of South Branch Kishwaukee River. Owner: McHenry County.
REVISIONS HISTORY -
Revisions: Land-surface datum was updated to 924.30 ft NAVD88 on May 30, 2023, as determined by a GNSS Level II survey. Land-surface datum was previously published as 924.14 ft NAVD88 (furnished). Discrete water-level measurements prior to May 30, 2023, are referenced to the original datum.
GROUNDWATER RECORDS
WELL CHARACTERISTICS - Depth 114.9 ft. Upper casing diameter undefined; top of first opening 109.9 ft, bottom of last opening 114.4 ft. Well-casing includes 2-inch schedule 40 PVC pipe, 8 in. diameter borehole with bentonite seal, observation well.
DATUM - Land-surface datum is 924.3 ft above North American Vertical Datum of 1988. Measuring point: Top of PVC Casing; High point marked, 2.46 ft above land-surface datum, Nov. 11, 2008 to Sep. 24, 2019; Top of PVC Casing; High point mark, 2.49 ft above land-surface datum, Sep. 23, 2019 to Apr. 1, 2021; Top of PVC Casing; High point mark, 2.47 ft above land-surface datum, Apr. 1, 2021 to present.
PERIOD OF RECORD -
GROUND-WATER LEVELS: February 2009 to current.
GROUND-WATER QUALITY:
CHEMICAL: Water year 2011.
GAGE - Water level recorder and satellite telemeter.
EXTREMES FOR PERIOD OF RECORD - Highest water level, 30.35 ft below land-surface datum, May 24, 2020; lowest, 43.18 ft below land-surface datum, December 19, 2012 and January 9, 2013.