Weekend Project: Plant a Rain Garden

Lately, DC has received its fair share of rain. Ordinarily, this rain runs off of impervious surfaces like buildings, streets, sidewalks, etc. and flows into drains built at the bottom of slopes and in depressions. Those drains dump the rain into streams and rivers, carrying chemicals, oil and toxins with it.

Back in 1990, a developer in Prince George’s County came up with a solution to stop rain water from flowing into rivers and streams. He advocated planting gardens that are slightly depressed from the surrounding land, so water can flow down into the garden when it rained. He began integrating these “rain gardens” into properties in the Somerset subdivision he was developing. The idea was cost-effective and the gardens reduced stormwater runoff by 75-80%.

The secret to the success of rain gardens is soil. Soil is highly absorbent and great at redistributing water. As an added benefit, the layers of soil and the plants’ roots help filter pollution from rain water as it seeps into our groundwater supply, leaving us all with cleaner drinking water.

Planting your own rain garden is relatively easy.

First, identify areas in your yard or neighborhood where rain naturally flows. In your yard this will probably be near your roof’s drainpipe or a slope.

Second, carve a slight depression in the area where you’ll build your garden so water will naturally flow into the soil.

Third, make sure your soil is permeable enough to allow water to drain and filter properly. If it doesn’t, mix 60% sand, 20% compost and 20% topsoil to fill in the garden.

Finally, select native species of plants that are tolerant of both saturated and dry soil. Wildflowers, sedges, rushes, ferns, shrubs and small trees can be perfect for this use. Choose the right combination of plants and you could attract butterflies and birds.

If you’re curious to see a rain garden in action, visit the Chevy Chase Community Center and Library at 5601 Connecticut  Ave. NW. Friends of Rock Creek’s Environment build the rain garden as a demonstration project for the District Department of the Environment’s RiverSmart Homes Program. You can learn more about the Chevy Chase Rain Garden HERE and you can learn more about DDOE’s RiverSmart Homes Program HERE.

Photo Credit: Flickr CC User bobrpics