The upper west branch Brandywine subwatershed is a 6.2 square mile catchment area in Honey Brook Township. The headwaters are in the Welsh Mountains near the Lancaster and Berks County borders and flow south through Honey Brook Township east of Route 322. PADEP has listed the stream as impaired by sediment, nutrients and agricultural pathogens. Land use is primarily agriculture with a focus on field crops and dairy. The upper west branch and its unnamed tributaries are classified by PADEP as High Quality-Trout Stocked Fishery/Migratory Fishery.
- With funding from the City of Wilmington and the Chester County Solid Waste Authority an Assessment Report and a Restoration Plan were completed in August 2010
- A PADEP Growing Greener Grant of $457,000 to the Chester County Conservation District in 2012 supported the design and permitting of three stream restorations on dairy farms. Funding was also provided by William Penn Foundation, the City of Wilmington, and the Chester County Solid Waste Authority.
- Construction of the three stream restorations took place from October 2014 to January 2016. Over 1,000 trees and shrubs were planted at the three restoration sites.
- 8,500 feet of stream fencing installed with livestock crossings.