Parking lots get tiny parks, to be 'rain gardens'

There is a whole lot of asphalt on the western end of the Rowan University campus in Glassboro.

They didn't recently pave paradise to put up a parking lot. The lots that serve Richard Wacker Stadium, nearby university buildings, and Glassboro High School across the street are from decades ago.

But Jess Everett's civil engineering classes, along with the engineering firm Princeton Hydro and the Gloucester County and Camden County Soil Conservation Districts, are trying to turn the nondescript parking areas "green" - in a pilot program that involves planting "rain gardens."

"It seems like a small project, but boy, will we notice a difference," said Clay Emerson, the lead resource engineer on the project for Princeton Hydro and a 2000 Rowan engineering graduate. "By spring, it will all be beautiful and have a great effect."

Asphalted land, noted Everett, a Rowan professor of civil and environmental engineering, is typically just drained by a storm sewer at a low corner of a lot.

The water from a rainstorm collects there and is moved underground through pipes into a stream or river - in this case Chestnut Creek, then onward to Mantua Creek, and eventually to the Delaware River.

The problems with that, Everett said, are myriad.

The water contains pollutants from cars - oil drippings, chemicals off tires - and the surge that comes from the pipes during a rainstorm can cause "flash," as in flash flooding, suddenly accelerating the stream flow.

"If you are an organism or a fish in that stream, that means you can get a load of sludge on you or be pushed along too swiftly and could die," he said. "It is just not ecologically sound."

For students such as senior Brett Hoffmann of Colonia, N.J., the project has been a semester-long hands-on class. They have been helping Princeton Hydro measure water tables, determine proper gradings for drainage ditches, and plant vegetation that includes switch grasses, purple-cone flowers, hibiscus, black-eyed Susans, and asters.

"All these plants are suited for the environment," Hoffmann said.

It is not quite what a student of civil engineering, who might prefer building highways or skyscrapers, expects in a practicum, he said, "but it is really beneficial to getting the environment healthy."

The plantings are primarily inside newly created medians in the parking lots. These rain gardens' job is to intercept rainwater and let it slowly percolate into the ground rather than flood and run off into storm sewers.