USGS Water-Year Summary 2025
414948074035001 U-1619, at Tillson NY
Sand and gravel aquifers (glaciated regions)
Glacial Delta Deposits
LOCATION - Lat 41°49'48", long 74°03'50" referenced to North American Datum of 1983, Ulster County, NY, Hydrologic Unit 02020007, Grist Mill Road, at Tillson.
GROUNDWATER RECORDS
WELL CHARACTERISTICS - Depth 41 ft. Upper casing diameter 2 in; top of first opening 32 ft, bottom of last opening 37 ft. Well filled in from original depth of 42.3 ft, cased to 32 ft (screen, 32 ft to 37 ft).
DATUM - Land-surface datum is 236.41 ft above North American Vertical Datum of 1988. Measuring point: Top of casing, 3.41 ft above land-surface datum, Jul. 29, 2002 to Jul. 14, 2012; Top of shelter shelf, 3.45 ft above land-surface datum, Aug. 20, 2013 to Oct. 17, 2023; Top of shelter shelf, 3.47 ft above land-surface datum, Oct. 17, 2023 to present.
PERIOD OF RECORD - July 2002 to current year.
GAGE - Water-stage recorder--15 minute; periodic manual measurements by USGS personnel.
EXTREMES FOR PERIOD OF RECORD - Highest water level, 13.71 ft below land-surface datum, Sept. 13, 2011; lowest water level, 20.76 ft below land-surface datum, Oct. 10, 11, 2002.