U.S. Geological Survey cooperative water-resources programs in Chester County, Pennsylvania

Since 1969, the U.S. Geological Survey (USGS) has had a cooperative water-resources investigation program with Chester County to measure and describe the water resources of the County. Generally, the USGS provides one-half of the program funding, and local cooperators are required to provide matching funds. Cooperation has been primarily with the Chester County Water Resources Authority (CCWRA), with participation from the Chester County Health Department and funding from the Chester County Board of Commissioners. Municipalities and the Red Clay Valley Association also have provided part of the funding for several projects. This report describes how the long-term partnership between the USGS and Chester County, Pa., provides the County with the information that it needs for sound water-resources management.

The CCWRA was created in 1961, primarily for land acquisition and planning for flood-control and water-supply projects. With the backing of the Brandywine Valley Association, the CCWRA started its first cooperative project with the USGS in 1969. It was a study of the water-quality condition of Chester County streams with an emphasis on benthic macroinvertebrates and stream chemistry.

The kinds of projects and data collection conducted by the USGS have changed with the needs of Chester County and the mission of the CCWRA. Chester County is experiencing rapid population growth (it had the tenth-highest rate of growth in the nation from 1980 to 1990). This growth places considerable stress on water resources and has caused the CCWRA to broaden its focus from flood control to water-supply planning, water quality, and ground-water and surface-water management. The results of USGS studies are used by the CCWRA and other County agencies, including the Planning Commission, Health Department, and Parks and Recreation Department, for conducting day-to-day activities and planning for future growth. The results also are used by the CCWRA to provide guidance and technical assistance to municipalities, water suppliers, industrial dischargers, watershed and conservancy associations and other civic organizations, state and Federal agencies, river basin commissions, and the private sector.

The cooperative water-resources program, which is described in the following sections, benefits not only the citizens of Chester County but also serves the interests of the Federal Government. Innovative studies conducted in Chester County provide methods and interpretations that often can be used nationwide, and the headwaters of several interstate drainages lie within the County. Major program thrusts include collection of surface-water, ground-water, and water-quality data and interpretive studies. The use of this information also is described.