RETTEW worked with West Hempfield Township to develop a comprehensive, cost-effective strategy to achieve required sediment reduction loads in compliance with their 2018-2023 MS4 Permit requirements. This strategy included a variety of green infrastructure best management practices to reduce stormwater rates and volumes, increase groundwater supplies, filter stormwater pollutants, increase biodiversity and habitat for native wildlife species, and restore ecological balance.
Murry Ridge Park includes two regulated outfalls that discharge stormwater runoff directly to a small unnamed tributary of the West Branch of the Little Conestoga Creek Watershed. Stormwater within the park is managed by a series of inlets, pipes, and a large dry detention basin that collectively discharge polluted stormwater directly into a small stream flowing through the middle of the park. To reduce stormwater pollution, the Township diverted stormwater runoff to a vegetated swale and bioretention basin prior to discharging to the stream, installed a riparian buffer and native meadow plantings, and retrofitted a dry detention basin into a dry extended detention basin. The Township also installed a pedestrian walkway and pet waste system, and plans to install educational signage. RETTEW worked with the Township to secure and administer a $75,000 Grant from the Lancaster County Clean Water Fund and the Township’s Public Works staff implemented this project.