Assessment of the Transport of Nutrients in Ground-Water Discharge to the Coastal Bays Adjacent to Assateague Island National Seashore, Maryland
WRD PROJECT #: MD191
PROJECT CHIEF: Dillow, Jonathan J.A.
BEGIN DATE: 01-October-1998
END DATE: 30-September-2001
Customers currently supporting the project:
U.S. Geological Survey
Problem
The delivery of excessive nutrients to the estuaries of the Mid-Atlantic Coastal Plain is a regional problem for the management of natural resources because of the potential for adversely impacting the estuarine ecosystems. The coastal bays behind the Fenwick and Assateague barrier islands in Maryland and Virginia are particularly susceptible to environmental degradation from the accumulation of nutrients because of their physical and hydrological characteristics. Recent surveys of the biotic resources of the coastal bays have documented measurable stress to the system and significant changes in community structure.
Objectives
The proposed project is a three-year intensive study to estimate the total flux of nutrients transported by ground water to tidal streams and the coastal bays system. This information can be used by the resource managers of the National Park Service and the State of Maryland to develop strategies for controlling or mitigating the effects of excessive nutrients on the natural ecosystem. The study objectives are:
- Quantify the total flux of nutrients from ground-water discharge into Chincoteague, Newport, and Sinepuxent bays.
- Relate spatial differences in discharge of ground-water nutrients to land
Approach
The design of the field study includes three main components: (1) a series of synoptic surveys of the streams in the coastal bays watershed to measure water quality under base-flow conditions; (2) installation of monitoring wells to measure ground-water properties (including water quality, hydraulic gradients, and age/residence time) at five representative transects next to the bay shoreline or tidal tributaries; and (3) measurements to evaluate the spatial and temporal distribution of ground-water discharge directly to the estuaries by sampling a dense mini-piezometer grid immediately offshore from the monitoring-well sites. The data set will be used to develop an interpretive map of the distribution of the flux of nutrients from ground water discharge to the coastal bays system. The distribution of nutrient fluxes can be compared directly with other spatial databases available to the NPS as GIS coverages to infer relationships between nutrient loads and the physical processes and biotic responses of the coastal bays ecosystem.
For More Information
For more information about this project, please contact the Maryland-Delaware-D.C. District. The District can be reached by email by clicking here, by telephone at 443-498-5500, or by mail at U.S. Geological Survey, 5522 Research Park Drive, Baltimore MD, 21228.
