Watershed Conservation

The Conservancy works to understand threats to waterways and improve conditions. All streams in Lower Merion and Narberth are designated as impaired by the Pennsylvania Department of Environmental Protection, as are most streams in neighboring communities. Some of these impaired streams (including Mill Creek and Vine Creek) flow into the Schuylkill River upstream of drinking water intakes while others (including Cobbs Creek and its tributaries the East and West Branches of Indian Creek and Naylors Run) contribute to downstream flooding in Darby, Yeadon, and Eastwick.

The impairments are caused by our approach to development. Many buildings and roads are designed to channel rain water away as soon as it hits the ground. This water sweeps up pollutants – heavy metals, fertilizers, pesticides, motor oils, road salt, sediment, litter – before being funneled down a storm drain. From there the water is piped into a stream, untreated. The quantity of rain being channeled causes flooding on streets and in streams. The systemic nature of these issues calls for holistic solutions.

A better approach to handling rain is to create spaces for rain to percolate into the ground near where it lands, as it would in a natural setting, rather than piping it away. Rain gardens are a great way to capture water that would have otherwise run off from a roof or driveway. Planting trees and replacing pavement and lawns with native plant gardens also decreases runoff.   

The Conservancy installs projects ranging from residential scale native plant gardens to ecological restorations in parks to improve conditions wherever we can. To expand our reach, we worked with our partners at Pennsylvania Resources Council, Eastern Delaware County Stormwater Collaborative, and Darby Creek Valley Association to create the Growing Greener Communities website. The website walks through actions you can take at home to benefit your local stream.