Anne Arundel County Observation-Well Network
Project Details
- Latest Data Report:Hydrographs and tables showing ground-water level and pumpage records for selected observation wells in Anne Arundel County, Maryland and hydrograph showing surface-water flow in Sawmill Creek, 2022 report [3.4 MB])
- Project Data:Explore an interactive map with links to current water levels
Continuous water-level data - Project Staff:Isabel Glasman
The Anne Arundel County water-level network is one of three county observation-well networks maintained by MGS and funded through county cooperative agreements. Other counties include Charles and Queen Anne’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 Anne Arundel County observation-well network, initiated in 1986, is currently funded through a cooperative agreement between Maryland Geological Survey and Anne Arundel County Department of Public Works. The network consists of 41 wells located mainly in the central and northern part of the County. Aquifers monitored include the Patuxent (7 wells), Lower Patapsco (19 wells), Upper Patapsco (8 wells), Magothy (6 wells), and Aquia (1 well). Frequency of measurement is 6 times a year, semiannual (spring and fall), or continuous.
Current Water-Level Trends
Aquia aquifer
Water levels were measured in one well in this aquifer. The water level in Southern Anne Arundel County at the Deale Athletic Field (AA Fe 92) was 31.96 ft below sea level in September, 2021. While fluctuating seasonally by as much as ~5 feet as a result of local pumpage, the overall water-level trend since about 2006 has been relatively flat. The flattening of the trend is largely a result of the reduction of withdrawals from the Aquia aquifer in St. Mary’s County as pumpage was shifted to the deeper Upper Patapsco aquifer to avoid elevated arsenic concentrations in the Aquia aquifer.
Magothy aquifer
Water levels were measured in 6 wells in this aquifer. Current levels range from 3.47 ft above sea level west of Annapolis (AA Dd 42) to 23.65 ft below sea level in Broad Neck (AA Cf 99). Overall, water levels show a relatively flat trend with seasonal fluctuation due to water use over the last ten years.
Upper Patapsco aquifer
Water levels were measured in 8 wells in this aquifer. Current levels range from 72.35 ft above sea level in northern Anne Arundel County (AA Ad 108) to 30.98 ft below sea level at the Broad Creek Water Treatment Plant (AA De 95). Overall, water-levels in the Upper Patapsco aquifer exhibit a flat to slightly increasing trend in most of the county.
Lower Patapsco aquifer
Water levels were measured in 19 wells in this aquifer. Current levels range from 76.93 ft above sea level in northern Anne Arundel County (AA Bd 160) to 66.70 ft below sea level in the Arnold well field (AA Cf 167). Recent pumpage in Crofton ranged from 4.66 million gallons per day (Feb 2022) to 6.75 million gallons per day (Sept 2021). In Arnold, recent pumpage ranged from 3.54 million gallons per day (March 2022) to 7.18 million gallons per day (July 2021). Overall, water level trends are flat to slightly increasing in all wells except at Kings Heights (AA Cc 82), where a slightly declining trend is observed.
Patuxent aquifer
Water levels were measured in 7 wells in this aquifer. Current levels range from 17.14 ft above sea level south of Ft. Meade (AA Cb 1) to 110.50 ft below sea level in the Arnold well field (AA Cf 166). Recent pumpage in Crofton ranged from 5.53 million gallons per day (Oct 2021) to 6.40 million gallons per day (June 2022). Recent pumpage in Arnold ranged from 1.03 million gallons per day (March 2022) to 3.79 million gallons per day (July 2021). Overall, water levels in wells in the Patuxent aquifer have declined in the last 10 years, with the exception of those at Glen Burnie (AA Ad 90) and Arnold (AA Cf 166) which have shown a flat and increasing trend, respectively.