HomeMy WebLinkAboutCityofEdinaFloodResilienceFactSheets-03-24-2020_Rain GardensFor more information on flood resilience, contact the Engineering Department at 952-826-0371.
1According to the Rain Garden Alliance, a do-it-yourself rain garden will cost about $3–$5 a square foot. If you use a landscaper to plan and install the garden, the cost will be
$10–$15 a square foot or more. Plants are the most costly consideration in a rain garden. Parts of the City of Edina are within the Nine Mile Creek Watershed District, which
offers cost-share grants for rain gardens. The minimum grant is $500 and requires a 25% match. To see if your home is located within the district and to learn more about the
grant program, go to https://www.ninemilecreek.org/.
Other considerations
• Rain gardens require partial to full sun. They should be built at
least 10 feet away from your home to prevent water damage to
foundations and basements.
• Rain gardens are typically 100 to 300 square feet, depending
on the slope of the surrounding landscape and the size of the
area draining to it; a garden will typically handle runoff from an
impervious area three times its size. More than one garden may be
needed to handle runoff from large surfaces (e.g., large rooftops).
• To prevent plants from drowning and mosquitoes from breeding,
a rain garden requires soil that is porous enough to soak up water
within 48 hours of a rainstorm. You can test your soil by digging a
wide 10-inch-deep hole, filling it with water, and observing whether
the water disappears within 48 hours.
• Before you dig, contact Gopher State One Call (811) or visit http://
www.gopherstateonecall.org/to locate electrical, gas, or telephone
lines.
What is a rain garden?
A rain garden is a tool used to decrease runoff and filter
pollutants from stormwater. These gardens, built in shallow
depressions, are filled with long-rooted grasses and plants
that soak up rainwater from impervious surfaces—before
the polluted flow enters lakes, rivers, and wetlands. Because
they decrease runoff, rain gardens are also useful in flood
prevention. Once established, they require little watering and
minimal maintenance.
In addition to decreasing runoff and filtering pollutants, rain
gardens also create habitat for birds and butterflies, recharge
groundwater, reduce mosquito breeding, and enhance
property value.
Actions for Flood Resilient Homes:
Rain Gardens
How do I plant a rain garden?
There are many online resources that provide
guidance on the construction and maintenance of
rain gardens, including:
Rain Garden FAQs, Rain Garden Alliance
Rain Gardens Provide a Healthy Corrective to Runoff Flooding,
WisContext
How and Why to Build a Rain Garden, U of M Extension
How Much Does a Rain Garden Cost?, Cost Helper
USDA Rain Garden Fact Sheet, USDA
Nine Mile Creek Watershed District Grants
How to Create an Effective Rain Garden, Habitat Network
Rain Gardens in Minnesota, Natural Resources Conservation Service
Who should use a rain garden?
Rain gardens are particularly beneficial for those who have a large amount of nearby impervious surface (rooftops, walkways,
driveways), have downspouts running into the lawn, or areas downhill from a downspout. They may also be helpful if you have
soil erosion. (With deep-rooted plants, rain gardens hold soil in place and prevent erosion).
image courtesy of Minnehahacreek.org
image courtesy Natural Shore:
http://www.naturalshore.com/rain-garden-project-album/
Reduces vulnerability
COST: VARIES1
Reduces exposure
Before flood action During flood action After flood action