A project years in the making took a big step last week toward a cleaner, healthier Little Buffalo Creek.
A collaboration between the Crow Wing Soil and Water Conservation District (SWCD), city of Brainerd, University of Minnesota (U of M) Extension and Master Gardeners, the project's first phase includes planting rain gardens in areas identified as most beneficial to the stream, which runs through south Brainerd into the Mississippi River.
Rain gardens are shallow depressions planted with native grasses, shrubs, flowers and other flood-tolerant species. These gardens are designed to collect stormwater runoff and snow melt, naturally filtering the water and removing pollutants before returning it to the groundwater below.
Runoff management is important for homeowners and businesses in urban areas and near lakes or rivers, where water unable to penetrate the soil collects pollutants from impervious surfaces, like streets or driveways, and drains directly into surface water.
Pollution is not the only concern when it comes to runoff. Increasing amounts and increased speed of flow from large paved areas, such as parking lots, can create erosion issues. Hard surfaces also tend to heat the runoff, which, if allowed to enter bodies of water unchecked, can cause problems for aquatic life.
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Preventing direct runoff is particularly important with Little Buffalo Creek. Years of heavy stormwater runoff into the stream has led to erosion in several areas, most notably in an instance which SWCD district technician Beth Hippert identified as a catalyst for the restoration.
In 2009, Brainerd resident Charlie Cooper, who lived on the creek, lost nearly his entire backyard overnight after an eroded bank finally gave way.
"The changes had been happening over time," said Hippert, who is leading the project. "At one point, the tipping point comes."
Erosion is not the only problem faced by the stream. The Minnesota Pollution Control Agency has listed Little Buffalo Creek on its impaired waters list for possessing characteristics not conducive for thriving fish and invertebrate populations.
A lack of oxygen in the water due to high temperatures and sediment has an impact on aquatic plants and animals, Hippert said, and this has been demonstrated by samplings of the creek's ecosystem.
Temperature samples collected by Owen Baird, fisheries specialist with the Minnesota Department of Natural Resources, showed the creek could support trout except after it rained, when temperatures rose to levels too hot to sustain the species.
"To me, that really says it all," said Hippert. "To affect water that quickly - that's a lot of water - and the temperature difference is huge."
Hippert also noted a sampling of macroinvertebrates (such as insects or crustaceans) in the creek, which showed the populations were impaired. Beyond low oxygen levels, pollutants such as soap or road salt can also affect the breathing of these animals.
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"You need the larvae for the fish population," she said. "So many animals are dependent on those small microorganisms and people don't even notice."
Here's where the rain gardens come in. Instead of stormwater continuing down a paved street, accumulating chemicals on the road in its path and heating up, curb cuts will direct water into the gardens, where it will nurture plants that will nurture it back, returning it to the ground refreshed.
"You can't fix the stream if you aren't reconnecting the stormwater to the soil," Hippert said. "It's the natural system."
Plants used in the rain gardens all grow naturally within 100 miles of Brainerd.
"All these plants have lived and grown together for 10,000 years," she said. "The genotype is adapted to the soils and moisture and the temperatures we have here."
Last May, Hippert began canvassing Little Buffalo Hills, the neighborhood southwest of where the creek runs in culverts beneath South Sixth Street. Her task: convince homeowners to install these wild-looking gardens in their manicured front lawns.
Hippert said she targeted properties located upstream of storm drains with enough space to plant the gardens.
As part of a one-time grant from the Clean Water Fund established through the Legacy Amendment, the rain gardens, with an estimated value of $4,000 each, were offered free of charge to the homeowners. In exchange, 17 homeowners agreed to choose a planting design, provide labor at planting time and sign a contract with SWCD to maintain the gardens for 10 years.
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Whether greenhorns or green thumbs, the homeowners won't have to go it alone with their gardens. A team of 18 Master Gardeners and interns volunteered to assist with planting and will return throughout the following year to ensure the gardens are functioning as intended, to help identify weeds and instruct on maintenance.
Brainerd city employees will also help with maintaining the gardens, cleaning out filter boxes at the curb cuts that prevent large debris from floating in.
Dwight Simonson and wife Kathy live on Graydon Avenue and own one of the properties with a new rain garden.
"Our front lawn was a mess anyway, so I thought, 'Well, a garden will look good there,'" Simonson joked.
Simonson, a former township supervisor in the Leech Lake area, said he was more familiar with invasive species than with water runoff issues before getting involved in the project.
"People don't understand how the drainage works in the Mississippi," he said. "It's about keeping the environment safe and happy ... it's a good thing for everybody."
Down the street, Deb Hoffman of Brainerd was busy planting another new rain garden at the home of Tom and Marilee Larson. Hoffman and husband Louie, both Master Gardeners for eight years, volunteered for the project because they believe in rain gardens.
"The difference in the amount of chemicals and all the bad stuff going into the water was just amazing," said Deb Hoffman. "And it's all because you dig a hole and you make the water go in the direction it's supposed to go."
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At a property right next to the creek, Wayne Gutzman said he didn't know much about the ecology involved, but was convinced to plant a garden when Hippert visited his and wife Joan's home.
"Beth came along and put a sell job on me and said it was necessary," Gutzman laughed.
He said a tremendous amount of water flows downhill in front of his house during storms, and at times, the nearby storm drain overflows.
"This will absolutely settle the water," he said.
Hippert estimated the rain gardens will divert at least 15,000 gallons of stormwater in a one-inch rain event, or enough to fill more than 270 rain barrels.
Next summer, SWCD will continue with the second phase of the revitalization project, which involves working with homeowners on the stream on innovative approaches to bank stabilization to directly impact erosion issues.
Hippert said taking an ecologically beneficial approach to solving problems like those faced by Little Buffalo Creek yields better results.
"SWCD really goes for sustainability and resilience," she said.
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SIDEBAR: Planting a rain garden
Native plants work best for rain gardens, because they are adapted to the weather and soil conditions of the region. Plants range from those that tolerate standing water to those that prefer mesic (partially wet) or dry conditions.
Rain gardens aren't only for function; they can also be beautiful and attract pollinators.
Following is a list of plants that work well in rain gardens.
Butterfly weed - Orange or yellow clusters of flowers. Grows 1-2 feet, prefers dry or mesic conditions.
Narrow-leaved milkweed - Greenish-white clusters. Grows 1-3 feet, prefers dry or mesic.
Stiff tickseed - Long-lasting bright yellow flowers. Grows 1-2 feet, prefers dry or mesic.
Culver's root - Long spikes of white to blue flowers. Grows 3-5 feet, prefers dry or mesic.
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Obedient plant - A clump of pink or white flowers. Grows 1-4 feet, prefers mesic or wet.
Swamp milkweed - Pink to mauve clusters of flowers. Grows 3-4 feet, prefers mesic or wet.
Stiff goldenrod - Clusters of yellow flowers. Grows 1-4 feet, prefers mesic or wet.
Prairie dropseed - A prairie grass. Grows 1-2 feet, prefers dry or mesic.
Brown fox sedge - A sedge whose seed head resembles a fox tail. Grows 1 foot tall, prefers mesic or wet.
Blue-joint grass - One of the most abundant prairie grasses on the continent. Grows 2-5 feet, prefers mesic or wet.
Little bluestem - Grass with a blue tint. Grows 1-3 feet, prefers dry or mesic.
The U of M Extension office has several resources on rain gardens. For a more extensive list of rain garden plants, visit www.extension.umn.edu/garden/yard-garden/landscaping/best-plants-for-tou... .
For information on building your own, visit www.extension.umn.edu/environment/shoreland/lake-home-and-cabin-kit/docs... .
Adapted from information provided by SWCD.
