USING GIS TO PLAN AND MANAGE WATER QUALITY ISSUES
A CASE STUDY OF CHOPTANK WATERSHED

Choptank Watershed
The Choptank River is a major tributary of the Chesapeake Bay and is located on the Delmarva Peninsula. The Choptank watershed includes portions of Caroline, Dorchester, Queen Anne's and Talbot Counties in Maryland and Kent County in Delaware. The river originates in Kent County, Delaware, and flows southwest; the river becomes tidally-controlled near Greensboro, Maryland. Other large water bodies in this watershed include the Choptank, Little Choptank, Tred Avon River, Broad, Harris, and Tuckahoe Creeks. The river is tidal for most of its length and includes an ecologically delicate estuarine ecosystem. The soils in the region are poorly-drained and the topography is flat; therefore, farmers have traditionally  utilized networks of drainage ditches to facilitate the movement of water into streams. The 2000 census population for the Maryland portion of the Choptank River watershed was 71,000. Cambridge is one of the biggest cities in the watershed with a population of in 12,503  and a population change  of +14.6% since 2000.

Map 1: The map below shows the Choptank Watershed and the subwatersheds that are discussed in this module.