Queen Anne's County Observation-Well Network
The Queen Anne's County water-level network is one of five observation-well networks maintained by MGS and funded through cooperative agreements with Anne Arundel, Calvert, Charles, Queen Anne’s, and St. Mary’s 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
Water levels are measured in two wells in the Surficial aquifer (Barclay and Grasonville). Water levels fluctuate seasonally up to nine feet, with no long-term decline. Current water levels range from about 68 ft above sea level (QA Cg 69) to 13 ft above sea level (QA Ec 1).
Water levels are measured in seventeen wells in the Aquia aquifer, most of which are located on Kent Island. Most wells show seasonal variation, with the lower water levels recorded in late summer and higher water levels in spring. Long-term trends are stable or show a slight rise in water levels. Current water levels range from the highest at about 16 ft above sea level (QA Be 17) to the lowest at about 18 ft below sea level (QA Fc 7).
One well (QA Ea 27) is completed in the Magothy aquifer. The water level has shown a steady decline of about 0.6 ft per year over the last several decades. Since 2015, water levels have leveled off. Current water levels are about 21 ft below sea level.
Upper Patapsco aquifer
Three wells are completed in the Upper Patapsco aquifer. These wells, which are located in Tuckahoe State Park (QA Ef 29), Kent Island (QA Eb 111), and Kingstown (QA Be 16), show fairly steady water-level declines of between 1.0 to 1.5 ft per year over the past twenty years, reflecting pumping effects in Anne Arundel County and Easton. Current water levels range from the highest at about 18 ft below sea level (QA Be 16) to the lowest at about 23 ft below sea level (QA Ef 29).
Lower Patapsco aquifer
Three wells are completed in the Lower Patapsco aquifer. Water levels in two of the wells (QA Be 15 and Eb 112) have declined less than 1 ft per year over the past 15 years. The water level in well QA Eb 112 appears to be leveling off over the last three years. The long-term trend in the third well (QA Eb 182) can’t be determined due to the spotty record. Current water levels range from the highest at about 7 ft below sea level (QA Be 15) to the lowest at about 32 ft below sea level (QA Eb 182).
One well (QA Eb 110, near Chester on Kent Island) is completed in the Patuxent aquifer. The water level in this well had been declining steadily (~0.4 ft/year) between about 1988 and 2012. Beginning in 2012, the water level has been declining by about 1.25 ft/year, likely due to pumpage from the Arnold well field in Anne Arundel County, located about 12 miles west of QA Eb 110. Current water levels are about 11 ft below sea level.