The second portion of the Roxborough Reservoir Preserve is the Swale along Summit Avenue.
The outside has two narrow mown strips along Port Royal Avenue and Lare Street and two larger areas along Eva Street and Summit Avenue. The Summit section was the site of a Philadelphia Water Department storm management project in 2012 in which two large swales were dug and the nearby streets were recontoured to have rainwater flow into them.
This alleviated flooding problems in the immediate area and allows storm water to be filtered by the grasses planted in the swales before it is returned to the ground. Much of the soil dug from this project was placed in the second interior basin which was then also seeded and is now a developing native pollinator meadow.
The area along Summit Avenue is now jointly maintained by the Water Department and Parks and Recreation and the Roxborough Manayunk Conservancy, with the group doing most of the routine maintenance and improvements.