What are Best Management Practices?
Stormwater best management practices (BMP’s) are control measures or actions taken to mitigate changes or prevent the quantity and quality of stormwater runoff from causing water pollution. Stormwater BMP’s can be classified as “structural” or “non-structural” and can range from installations to changes in procedures. There are many ways to implement BMP’s, and methods of doing so vary based on the site and operation.
A raingarden is simply a garden with a depression planted with native plants designed to capture stormwater runoff from hard surfaces such as roofs, sidewalks, driveways, and your yard. Raingardens also provide a wildlife habitat and by soaking up the rainwater, it helps slow stormwater runoff, helps prevent erosion, and remove pollutants in the process. Think of it as a brita filter for stormwater runoff.
Two raingardens can be seen in this picture from the roof of the Delaware County Building. These raingardens capture all of the parking lot runoff and impervious cover runoff of the plaza. The raingardens also have retaining live walls with native plants growing in them, and four bump out infiltration strips on Walnut and Main Street. These BMP’s are designed to capture up to five 100 year flood events in a row before reaching it’s capacity.
Raingardens can be all shapes, depths and sizes. The can be designed to fit a residential or commercial property. Pictured here is a demonstration raingarden installed by workshop attendees at Minnetrista after doing a morning class with raingarden expert and author, Rusty Schmidt. This raingarden was designed to capture some of the stormwater runoff leaving a gravel parking lot at Minnetrista.
Residential raingardens can be designed to capture roof runoff, sump pump runoff or capture water flowing off your driveway or sidewalk. Designing the right size raingarden all depends on how much square foot of hard surface you are capturing. For more resources about designing a residential raingarden, visit our raingarden webpage.
Rain Barrels can be a very easy and affordable way to make an environmental impact in your community. Large amounts of stormwater runoff come off of your roof every time it rains and travels and picks up pollutants on the way to the stormdrain. Installing a rain barrel at the end of your downspouts has gotten easier and can also help prevent standing water in your yard.
Just imagine catching 65 gallons of rain during a 1 inch storm event instead of allowing it to flow as stormwater to a combined sewer system and eventually to the White River. The average roof collects an estimated 22,500 gallons of rain a year. That’s enough to fill over 345- 65 gallon rain barrels a year with free water! Capture all of this free rainwater to water house plants, flower gardens, vegetable gardens, mop your floor, wash your car, etc. Plants prefer rainwater instead of treated tap water.
Porous Pavement and Bioswales
Canan Commons, a new downtown performance park, offers an assortment of BMP’s including a porous pavement walkway that allows water to percolate through it instead of creating stormwater runoff. This new park also has a variety of native plants, flowers and trees planted in bioswales throughout the park. Stormwater runoff that falls in these swales is absorbed by the native plants and trees that are planted in them.
Curb cuts, like the one found at the Madison and Walnut Street roundabouts pictured here, allow stormwater runoff to enter green infrastructure to be absorbed by plants and other structures. Splash pads and entry points need to be maintained and cleaned out frequently because of the pollutants, sediment, and litter that is picked up through stormwater runoff.
Many buildings are now retrofitting there roofs to include green roofs and new builds are adding this best management practice in the original design. Green roofs can sometimes capture the first inch of rain that falls onto the roof, and in some cases more, before sending rainwater to downspouts that can also be diverted to other best management practices onsite. Here is a picture a newer green roof in Muncie, Indiana at the Open Door Health Clinic.
Best Management Practices can be found all around Muncie and Delaware County for citizens to check out and get ideas about you can do to incorporate some of these BMP’s on your property. We have put together a map showing some of the projects our Stormwater Department has worked on throughout the community.