Delaware's Watersheds

Technical Monitoring Sites

Click link below for site information and monitoring data

Appoquinimink Watershed - The Appoquinimink watershed drains 47 square miles in southern New Castle County with 3 municipalities; Middletown, Odessa, and Townsend, located within the watershed.  Historically this watershed has been rural and agricultural in land use. However in the past 5 years, a tremendous amount of growth and development has occurred. This has resulted large numbers of housing developments built in the watershed and changing the balance of land use from agricultural to suburban/residential. The sites being monitored were chosen to monitor the water as it enters the watershed from four different tributaries of the Appoquinimink and one site downstream of most of the development not too far upstream of where it enters the bay.


Brandywine Creek Watershed - The Brandywine Creek watershed is part of the larger Christina Basin, which flows into the Delaware River. While most of the 325 square mile Brandywine Creek watershed lies in Pennsylvania, the mouth of creek is located in Delaware. The area is known for its historic significance, as the location of the Revolutionary War's Battle of the Brandywine and as the birthplace of the DuPont Company. The Brandywine is also noted for its beauty, especially from a canoe. Many private and public park areas protect the rolling hills of the Delaware piedmont adjacent to the stream. All of the Technical Monitoring sites are located in these park areas and are second or third order streams.


Christina River Watershed - The Christina River encompasses 78 square miles in Delaware and Maryland and is one of the four sub-basins that make up the larger Christina Basin watershed. The other three sub-basins empty into the Christina River before it enters the Delaware River. The lower portion is tidal. The Christina River runs through downtown Wilmington and is the home of the Kalmar Nyckel, the tall ship of Delaware, which is a replica of the original ship that brought Swedish settlers to Delaware. It is also a critical part of the Riverfront revitalization in Wilmington and is the site of the Port of Wilmington, an important shipping link. All but two of the monitoring sites are located on the mainstem spread at fairly equal distances from the upper watershed to lower end near the mouth. The remaining two sites are located on small tributaries in the upper part of the watershed.


Mispillion Watershed - The Mispillion watershed is 73 square miles and approximately 50% agriculture and 24% forested. It serves as the boundary between Kent and Sussex counties. Milford is the largest town located within the watershed. There are four major water bodies in this watershed; Blairs Pond, Griffiths Lake, Haven Lake, and Silver Lake. These are all formed by damming the Mispillion. It is tidal up into the town of Milford. All monitoring sites are located on tributaries of the Mispillion.


Red Clay Creek Watershed - The Red Clay Creek sub-watershed covers 54 square miles in Delaware and Pennsylvania and has a long industrial history, having served as the site of several mills. The Wilmington and Western Railroad, which winds through the valley following the creek, once brought goods from the mills to the ports in Wilmington. The watershed was also the recipient of the Red Clay Valley Scenic Byway designation in April 2005. This designation recognizes that the quality of the remaining natural and scenic resources in this area is extremely significant. Four of the eight sites are on the mainstem while the other four are located on tributaries with one site being located on the state line.


White Clay Creek Watershed - The White Clay Creek watershed encompasses 107 square miles in Delaware and Pennsylvania and is one of four sub-basins that make up the larger Christina Basin watershed. The White Clay Creek was designated a National Wild and Scenic River by an act of Congress in October 2000. This designation preserves its free flowing waters and highlights the importance of its natural resources to the public. Only one of the nine monitoring sites is located on the mainstem of the river. Four of the remaining sites are all located on a single tributary (Pike Creek) where extensive streamside restoration has been implemented.