These lovely gardens reduce stormwater runoff
T he average rainfall per storm in Western Pennsylvania is about 1/4 inch, while as little as 1/10 inch can cause sewage and storm drains to overflow. Audubon Society of Western Pennsylvania is a founding member of the Three Rivers Rain Garden Alliance – a collaborative of nonprofit organizations, corporate entities, education institutions, and government agencies working together to encourage and facilitate the installation of rain gardens as one method of addressing the combined sewage overflow (CSO) and other wet weather runoff issues that plague our region.
A rain garden is natural-looking area built in a depression and designed to capture and filter runoff from impervious surfaces such as roof tops, driveways, and roads. Utilizing native perennials that “don’t mind getting their feet wet,” they are attractive, landscaped areas that help address storm water runoff while provide excellent habitat and food for native wildlife such as birds and butterflies.
Additional information on rain gardens can be found at Three Rivers Rain Garden Alliance, including tools to help you size and design your garden and a garden registration system that will keep track of the amount of water your garden retains.
Sample Rain Garden designs
These sample rain garden designs are for gardens sized to accommodate one inch of rain fall on an 800 sq foot roof area. They have a six inch depth and can hold up to 500 gallons per rain fall event. Your garden size, shape, and depth may be different depending on your garden location and the amount of water you are trying to retain.
Full sun garden
Click image to download the Full Sun plan
Partial shade Rain Garden
Click to download the Partial Shade plan
Other rain rater resources
These other topics are not strictly part of a rain garden. However, many people include them in their overall planning.
