Maryland Department of Natural Resources

Queen Anne's County Observation-Well Network

The Queen Anne's County water-level network is one of three county observation-well networks maintained by MGS and funded through county cooperative agreements. Other counties include Anne Arundel and Charles counties.

The primary objective of these networks is to monitor the effects of water-supply withdrawals on groundwater levels at both a local (well field) and regional scale. More specifically the water-level data are used to help assess (1) long-term sustainability of the water supply; (2) well interference (drawdown at each well in a multiple-well system added to drawdowns at the other wells); (3) potential for increased development of the aquifers; (4) potential for salt-water intrusion, where applicable; and (5) the role of ground-water extraction in land subsidence.

The Queen Anne's County observation-well network is currently funded through a cooperative agreement between Maryland Geological Survey and Queen Anne's County Department of Public Works. The network consists of 27 wells located mainly in the western (Kent Island) portion of the County. Aquifers monitored include the Surficial (Columbia) (2 wells), Aquia (17 wells), Magothy (1 well), Upper Patapsco (3 wells), Lower Patapsco (3 wells), and Patuxent (1 well). Frequency of measurement ranges from 12 times a year to semiannual (spring and fall).



Current Water Level Trends


Surficial aquifer

Water levels were measured in two wells in the unconfined surficial aquifer (at Barclay and Grasonville). Water levels fluctuate seasonally up to approximately five feet, and tend to be very responsive to precipitation and drought. Current water levels range from 68.09 ft above sea level at Barclay (QA Cg 69) to 16.52 ft above sea level at Grasonville (QA Ec 1). Water-level trends show a continuing increase at Barclay (QA Cg 69) while remaining flat at Grasonville (QA Ec 1).

Aquia aquifer

Water levels were measured in seventeen wells in this aquifer, thirteen of which are located on Kent Island. Most wells show less than 2 feet of seasonal fluctuation, with the lower water levels recorded in late summer and higher water levels in spring. Current water levels range from 17.13 ft above sea level at Kingstown (QA Be 17) to 24.46 ft below sea level at Prospect Plantation (QA Fc 7). Recently, water levels at Centerville (QA De 27) have fluctuated by as much as 12 feet, likely as a response to regional irrigation withdrawals. Overall, long-term trends are stable to slightly increasing.

Magothy aquifer

Water levels were measured in one well in the Magothy aquifer (Natural Resources Academy in Matapeake [QA Ea 27]). The most recent water level was 20.81 ft below sea level. Water levels in this well appear have stabilized since about 2014.

Upper Patapsco aquifer

Water levels were measured in three wells completed in this aquifer. Current water levels range from about 19.34 ft below sea level at Kingstown (QA Be 16) to about 24.50 ft below sea level at QA Ef 29 (Tuckahoe State Park). Overall water levels continue to decline at a rate of approximately 1 foot per year due to regional pumping in Anne Arundel, Queen Anne’s, and Talbot (Easton) counties.

Lower Patapsco aquifer

Water levels were measured in three wells completed in this aquifer. Current water levels range from about 7.64 ft below sea level at Kingstown (QA Be 15) to about 40.61 ft below sea level at Stevensville (QA Eb 182). Two of the wells, located at Kingstown (QA Be 15) and Chester (QA Eb 112), continue to decline at a rate of approximately 1 foot per year. The water level trend at Stevensville (QA Eb 182) is relatively flat; however, the well is likely affected by local withdrawals, making an assessment of trends difficult.

Patuxent aquifer

Water levels were measured in one well in the Patuxent aquifer at Chester (QA Eb 110). The current water level was about 14.81 ft below sea level. The steep decline starting in 2012 was a result of withdrawals from the Arnold well field in Anne Arundel County. Recently, water levels have declined about 3 feet since 2019.