Stormwater solution: Rain gardens green a church parking lot

A church parking lot sent runoff into a nearby creek. Now it contains rain gardens to absorb and treat the stormwater.

When Gerald Winegrad was a kid, he played baseball on grassy fields behind St. Mary's Catholic Church and School in downtown Annapolis. Over the years, as the church congregation and school enrollment grew, those grounds were paved over and turned into parking lots. Those parking lots serve as a highway for rainwater, sending it rushing into nearby Spa Creek, where it deposits chemicals, nutrients, and sediment and fouls the water.

Now there's been effort to undo some of that damage. With a grant from the state government, a partnership installed nine rain gardens to absorb and treat the stormwater.

"This is hopefully just the beginning," says Anne Guillette, of Pasadena-based Low Impact Design Studio, who drew up the plans for the rain gardens.

Curbs were cut away to direct water into the scooped-out areas, which were filled with water-loving plants. The rain gardens allow the stormwater to percolate gradually into the groundwater, just as it did before the area was paved over.

"They will capture the runoff," says Mr. Winegrad, a former state senator who heads the St. Mary's environmental stewardship committee.

The work was largely being paid for with a $104,000 grant from the state's Chesapeake Bay 2010 Trust Fund. Initially called the "green fund," the fund is a pot of money for on-the-ground pollution-control projects.

The church also kicked in at least $5,000, besides volunteer labor. Students at the school water and maintain the plants.

The parking lot at St. Mary's was identified as a potential project during a study of the creek watershed that was commissioned by the Spa Creek Conservancy. It's large and therefore sends a significant amount of pollution to the creek.

Volunteers with the conservancy worked on the project with the St. Mary's environment committee, the Redemptorists who own the land, and the folks who operate the historic Charles Carroll House next door, where one of the rain gardens will be located.

There also were additional layers of approval because of the site's historic nature. Another complicating factor was that the church needed to make sure no parking spaces would be lost in the project.

Shepherding the project through all the approvals was Spa Creek Conservancy volunteer Mel Wilkins. He says that in urban cities and towns like Annapolis, doing these kind of "retrofits" is the best way to help the environment.

The project at St. Mary's is one of several retrofits coordinated by Spa Creek Conservancy volunteers. Heritage Baptist Church on Forest Driver already has rain gardens, and projects are in the works with The Rockfish restaurant in Eastport and the St. Anne's Parish House up the street from St. Mary's.

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