A rain garden installed in the Powderhorn neighborhood of Minneapolis last year (Image courtesy of Metro Blooms)
A tornado in August 2009 knocked down trees and caused flooding at Phelps Park in the Bryant neighborhood of Minneapolis.
“That started some neighbors talking about bringing some aesthetics to the neighborhood,” said Bryant Neighborhood Organization board member Erin Schwarzbauer. “We were trying to just rethink how our backyards work, as well as our neighborhood as a whole.”
The neighborhood organization was looking for a solution to the flooding and loss of old trees. They were referred to Metro Blooms, a non-profit organization that promotes ecologically-friendly gardens and landscapes. Metro Blooms helped the Bryant neighbors plan about 15 rain gardens on the pathway of the new RiverLake Greenway, a bike boulevard that connects the Mississippi River to Lake Harriet.
“[It's] just kind of in an effort to make our small little neighborhood distinctive as people bike through and to bring that aesthetic of rain gardens to our neighborhood,” Schwarzbauer said.
A rain garden is a flat, bowl-shaped garden usually planted with native plants and grasses that’s used to prevent runoff from polluting nearby bodies of water.
Minneapolis has a goal of 3,000 rain gardens by 2015. Between 2009 and 2011, the number of rain gardens in the city jumped by almost 65 percent to 1,400, according to the city’s department of public works.
That growth has partly been fueled by neighborhood projects like in Bryant.
But the gardens are more than ornamental. They’re also designed to reduce the runoff to storm sewer systems, which often carries sediment and pollution into nearby bodies of water.
Last year Metro Blooms helped households in west Powderhorn plant 130 rain gardens to limit runoff to nearby Powderhorn Lake, said Metro Blooms Executive Director Becky Rice.
“It will capture the runoff before it leaves your property and allow it to infiltrate to the aquifers, so it can reach the rivers and the lakes and stream clean and cold,” Rice said.
Native plants are typically chosen for rain gardens because of their hardiness and deep roots, Rice said, making the gardens “relatively” easy to maintain.
“It’s a functional garden and it does require attention, but the plants can be fairly maintenance free,” Rice said. “Especially in an urban environment where people are planting in their front yard, they’re often looking for something [like a rain garden] that’s a little more controlled or a little more showy.”
Rain gardens also reduce impact on the city’s stormwater sewer systems, said Lois Eberhart, water resources administrator for the Minneapolis Public Works Department said.
“A lot of rain gardens are designed so the water soaks into the ground,” Eberhart said. “Soaking into the ground helps reduce the volume of stormwater runoff, so we have less stress on the system, less flooding, less erosion of creek banks.”
In Minneapolis, the effort of putting in a rain garden is rewarded by a reduction in stormwater utility fees that pay for stormwater infrastructure.
“Learning about rain gardens helps people think about other things they can do to improve lakes and the river,” Eberhart said. “When they have rain gardens and take pride in those, they’re more attentive to cleaning up pet waste, maybe sweeping up grass clippings to keep them out of the gutter.”
In Bryant, most neighbors who will receive rain gardens in June have already received their designs.
“They’re beautiful and people are excited to get them planted,” Schwarzbauer said. “There’s going to be an education piece during the installation, so other neighbors are able to watch the recipients getting their rain garden installed so they’ll be able to install their own.”