COS 160-3 - The State of Our Streams: Understanding Water Quality in the Headwaters of 3 Tributaries to the Delaware River in Southeastern Pennsylvania

Abstract: From 2018 through 2021, the Watershed Protection Program at Willistown Conservation Trust has conducted high frequency monthly water chemistry monitoring at ten sites in the headwaters of three tributaries to the Delaware River in Southeastern Pennsylvania. The goal of this study was to better understand the health and function of the headwaters of Ridley, Crum and Darby Creeks, to illuminate the impact of land protection efforts within the watershed and to motivate the public to support land protection and restoration efforts in the region.

Results from analysis of water chemistry data collected in Ridley, Crum and Darby Creeks indicate that water quality is moderately impaired at all sample sites. Elevated temperatures, chlorides, and specific conductivity presenting stressful conditions for many aquatic species, including freshwater mussels, are present in all three waterways. Elevated temperatures occur in the late spring and early summer, increasing stress levels for cold and cool water fish and macroinvertebrates. Increased chloride and conductivity levels are tightly linked to impervious surfaces within each watershed, with rapid increases in chloride concentrations and conductivity levels occurring in winter months. This data supports the critical role of land protection and open space management for maintaining and improving water quality in headwaters throughout the Delaware Basin as increases in development pressures and more frequent, high intensity storms call for better understanding of the cumulative effects on small order waterways.

Engaging the public in understanding the threats to headwater habitats is essential for future protection and restoration of sensitive aquatic ecosystems. The results and data from this study have been curated into a publication designed for a lay audience to engage residents in the Ridley, Crum and Darby Creek watersheds in order to create a scientifically literate public who are motivated to protect and restore their home watersheds. This case study presents a model of applied and inclusive practices for ecology for all people.