Title: Analysis of Surface Waters and Surrounding Wetland Habitats in the Lake Mercer Watershed

The Assunpink Creek Watershed is one of the most developed watersheds in New Jersey and, along with its tributaries (e.g., Shipetauken Creek, Shabakunk Creek, and Miry Run), has been determined to be moderately impaired (NJDEP, 1998) most likely as a result of urbanization. During development in the watershed, flooding became a problem (mainly in Trenton, NJ) and the Mercer County Board of Chosen Freeholders petitioned the United States Department of Agriculture, Soil Conservation Service to prepare the Assunpink Creek Watershed Work Plan (USDA, 1979). That plan recommended flooding be controlled with the installation of flood control basins in the headwaters of the Assunpink Creek. As a result, several were constructed including Robert L. Martin Lake impounding Pond Run (Veterans Park, Hamilton, NJ), Assunpink Lake impounding the Assunpink Creek (Millstone, NJ), and Lake Mercer (Mercer County Park, West Windsor, NJ) impounding Assunpink Creek.

Stream modification and non-point source pollutants associated with urban and agricultural land use, which combined cover 70-80% of the watershed, are likely contributors to the watershed impairments. However, we suspect that the configuration of the impoundments in the headwaters may also contribute to the problem. Recent investigations performed by the participants from the summer of 2000 WWNFF Environmental Science Program revealed that water quality in Pond Run of the Assunpink Watershed is most likely being impacted by the presence of the Robert L. Martin impoundment. For example, the benthic community located immediately downstream of the Martin Lake weir was categorized as poor while the community in the stream leading into the lake was categorized as fair.

The 2001 project will characterize the water quality of surface waters and the habitats surrounding them in the Lake Mercer Watershed which impounds Assunpink Creek. Land use in this watershed is primarily urban and agricultural. This project is part of a larger project underway by Kertes & Browne of all impoundment watersheds within the larger Assunpink Watershed to document the impact of these impoundments on the overall health of the Assunpink Watershed.

For the Lake Mercer Watershed, the WWNFF's participants will:

  • define current land use;
  • characterize water quality of surface waters;
  • characterize habitats in wetlands surrounding surface waters.

Participants electing this project should read the following prior to our first meeting. Other materials will be distributed on the first day.