by Janet Pinkerton
Under the gathering leaves, in the shallow swale beside the Lombard Street side of the playground fence, a rain garden is growing at Independence Charter School.
The rain garden was planted in October by ICS seventh grade science students guided by ICS parent and Pennsylvania Horticultural Society (PHS) staffer Julie Snell. As the plants take root, the rain garden will help absorb the storm water runoff from the playground and also provide ICS students with a new micro-environment in which to play, learn and explore.
The rain garden is a part of ICS’s larger environmental plan, designed with the assistance of PHS and the Philadelphia Water Department’s Office of Watersheds, to minimize the amount of rainwater running off the playground and into the Philadelphia sewer system. Philadelphia is an old city with Combined Sewer Overflow (CSO) system. During dry conditions and light rainfall, the CSO system functions. But during heavy rainstorms, storm water runoff surges into the sewer system, and the system gets over loaded. At these times, storm water and sanitary wastewater are both dumped into local streams and rivers.
ICS’s playground includes key structures, including the rain garden, that reduce the amount of rainwater it shunts into the sewer system. Approximately 3,000 sq. ft. of pervious paving allows water to penetrate to the ground below. The recently dedicated brick walkway, leading to the playground gate and inset with bricks emblazoned with the names of donors and honorees, slopes gently to channel rainwater from the playground into the rain garden. When rainwater falls onto the brick area, it is directed to a rock river and into the rain garden’s shallow swale. There, the collected water filters down through the soil with the help of the rain garden plants.