Maryland Department of Natural Resources

Queen Anne's County Observation-Well Network

Project Details

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 was initiated in 2000 and is currently funded through a cooperative agreement between Maryland Geological Survey and Queen Anne's County Department of Public Works. The network consists of 26 wells located mainly in the western (Kent Island) portion of the County. Aquifers monitored include the Surficial (Columbia) (2 wells), Aquia (16 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). In the past year, water levels fluctuated four to seven feet seasonally, with the higher value recorded in the Grasonville well (QA Ec 1). Current water levels range from 66.46 ft above sea level at Barclay (QA Cg 69) to 12.70 ft above sea level at Grasonville (QA Ec 1). Water-levels at Barclay (QA Cg 69) and Grasonville (QA Ec 1) continued to exhibit a generally flat trend.

Aquia aquifer

Water levels were measured in fifteen wells in this aquifer, thirteen of which are located on Kent Island. Most wells continued to fluctuate seasonally by less than 3 feet with the exception of Centerville (QA De 27), where levels fluctuated as much as 17 feet due to regional irrigation withdrawals. Current water levels range from 15.04 ft above sea level at Kingstown (QA Be 17) to 27.99 ft below sea level in Centreville (QA De 27). Overall, water levels in the Aquia aquifer continued to exhibit a slightly increasing trend on Kent Island, and a flat trend at Kingstown and Centreville. On November 12, 2024, the Aquia observation well at Mylander Farm (QA Db 35) was abandoned and removed from the network due to shoreline erosion and the resulting risk of being flooded by Chesapeake Bay.

Magothy aquifer

Water levels were measured in one well in the Magothy aquifer at the Natural Resources Police Academy in Matapeake (QA Ea 27). The most recent water level was 22.79 ft below sea level. Recent water levels in this well have continued to show a flat trend.

Upper Patapsco aquifer

Water levels were measured in three wells completed in this aquifer. Current water levels range from 22.57 ft below sea level in Chester (QA Eb 111) to 34.50 ft below sea level in Kingstown (QA Be 16). Over the past year, water levels in the well at Kingstown (QA Be 16) fluctuated seasonally as much as 11 feet. Overall water levels continued to exhibit a declining trend which is most likely due to regional pumping in Anne Arundel, Queen Anne’s, and Talbot counties.

Lower Patapsco aquifer

Water levels were measured in three wells completed in this aquifer. Current water levels range from 10.17 ft below sea level at Kingstown (QA Be 15) to 42.77 ft below sea level at Stevensville (QA Eb 182). Water levels in the Stevensville well (QA Eb 182) are affected by local pumping and do not reflect a long-term trend, but water levels in two of the wells, located at Kingstown (QA Be 15) and Chester (QA Eb 112), continue to decline at approximately one foot per year.

Patuxent aquifer

Water levels were measured in one well in the Patuxent aquifer at Chester (QA Eb 110). The most recent water level was about 18.73 ft below sea level. A steep decline starting in 2012 was a result of withdrawals from the Arnold well field in Anne Arundel County. In recent years, the water levels have continued to decline.