Main Entrance Basin (at right) – recently cut cattails and residual pickerelweed, June 2018 (Photo by Robert Pace)
When Cutler and Ryan Homes built the Stony Creek Farms (SCF) community in Montgomery County, PA, over the last ten years, they were challenged with what all developers are faced with when they convert open land to a development … they must develop the area in such a way that minimizes the impact to stormwater and streams. When areas covered in forest or open field are transformed to rooftops, paved driveways, and streets and other impermeable surfaces they alter the natural flow of water after it rains, which can result in serious impacts to flooding and water quality in the receiving streams. All water flows downhill and SCF waters flow to Stony Creek.
SCF, where I am a resident, is located in the upper and a relatively undeveloped part of the Stony Creek Watershed. Stony Creek meanders through our community as a minor stream, enlarges as it is joined by other branches and follows its course through the Norristown Farm Park, past the Elmwood Park Zoo until it ultimately flows a through a network of concrete channels in Norristown where it reaches the Schuylkill River. Eventually, these waters reach the Delaware Bay, one of the most environmentally and commercially important water bodies in our region. The 8 large basins in our community and the many rain gardens interspersed throughout were built by the developers to meet local, state, and federal stormwater management regulations that are intended to minimize flooding and protect the health of our streams. The vast majority of water that runs off of our driveways, parking lots, streets, and even lawns finds its way to one of our basins or rain gardens, either through storm drains on our streets or simply by flow over the land surface.
Our basins and rain gardens work to accomplish two things: First, they collect and detain the water that would otherwise flow unchecked to Stony Creek. In fact, our system is designed to handle the most commonly-occurring storms and rainfall based on statistical records of our area. If these waters otherwise reached Stony Creek unimpeded, they would cause severe erosion, undercut the stream channel and its banks, thus increasing its sediment load, and destroying valuable animal and fish habitat. Secondly, our basins and rain gardens work to ever-so-slowly filter the water through the marvelous vegetative buffers we created along their slopes and through the naturally-occurring and carefully planted vegetation and soil medium at the basin bottoms. By doing so, these features naturally remove pollutants such as oil and grease and dissolved metals that come from our road surfaces, nitrogen and phosphorus from application of fertilizers, and pathogens from natural and domestic animal waste. So ultimately, the water that runs off of SCF reaches Stony Creek in a relatively clean state, and is appreciably slowed and lessened, decreasing the potential for damaging flooding in downstream communities.
I have encouraged SCF residents that when they drive through or walk the trails by our basins and rain gardens, to take a moment to enjoy how lovely they are (and we are working to improve their look and effectiveness), but more importantly, to think about the important function that they serve. Much work goes into keeping these basins functional and appealing including annual inspections, maintenance, and enhancement activities. My role as the Chair of our community’s Stormwater Management and Basin Committee and as a Penn State Master Watershed Steward is to continue to look at ways to maintain and protect our basins and rain gardens so that they work as intended and provide an aesthetically pleasing amenity for our community. These experiences and techniques are “exportable” to other existing and developing communities around Pennsylvania.
Robert Pace – Master Watershed Steward, Montgomery County
For more information about stormwater management, go to the Stormwater Basics web page.