Home / Blogs / Rain gardens are effective tools to reduce stormwater runoff
June 28, 2022
Summer is here and with it, some of our favorite weather. Rising temperatures drive us to the water, where we enjoy a range of outdoor activities, including watching thunderstorms! While afternoon storms are often accompanied by welcome cooler air, they also bring sudden downpours and large volumes of water that come too fast for the ground to soak up.
What happens to all that water? In many cases, gutters empty along driveways or across short stretches of lawn where the water eventually finds its way into the closest storm drain. Heavy rain can drop water so fast that it doesn’t have time to soak into the ground before flowing into the nearest storm drain — or nearest creek.
Rainwater quickly flowing across the ground’s surface, or along paths and roads, often carries sediment, nutrients from lawns and crops, soaps from car washing, waste from livestock and pets, oil and litter from streets, and many more contaminants. All of that ends up in the closest waterway, and eventually the Chesapeake Bay itself.
Jordan Gochenaur, DC green infrastructure projects coordinator for the Alliance for the Chesapeake Bay, leads a tour of a newly installed rain garden at St. Catherine Laboure Catholic Church in Wheaton, MD. (Adam Miller/Alliance for the Chesapeake Bay)
From the far-reaching headwaters of Pennsylvania and New York to the Chesapeake, stormwater is a major source of pollution affecting the entire watershed. However, it also offers residents of the watershed great opportunities to get involved and make a difference, starting in their own backyards.
Rain gardens are effective tools to reduce stormwater runoff. Rain gardens come in all shapes and sizes, depending on the amount of water expected to enter them. A strategically placed rain garden acts as a bowl to temporarily collect and store stormwater runoff as it slowly drains into the underlying soil.
As with all plantings on your property, it’s best to use species native to the Bay region for your rain gardens. They not only provide habitat and food for native species as well as other ecosystem services, but typically require less maintenance than nonnatives. Because they are adapted to the climate and soil, they generally require little or no water, fertilizer or pesticides. They are also more likely to attract valuable native pollinators, from bees and birds to butterflies and beetles.
The rain garden at St. Catherine Laboure Catholic Church in Wheaton, MD, collects water after a rainstorm, allowing it to soak slowly into the ground. (Jordan Gochenaur/Alliance for the Chesapeake Bay)
Native plants can also decrease the amount of lawn that must be mowed, saving time and, if gas-powered mowers and trimmers are involved, reducing air pollution. If you think your property may benefit by installing a rain garden, you may want to consult a professional, or at least consider these recommendations:
Small steps to diffuse and slow rainwater before it can enter a storm drain can have a significant impact on the water quality of local streams and rivers. Imagine the benefits if everyone redirected the water flow from just one of their downspouts.
Green Infrastructure Program Director
(202) 210 1946