Major improvements to Mallets Creek shoreline under way along Washtenaw Avenue
Angela Cesere | AnnArbor.com
A $2.8 million restoration project along a roughly 1.5-mile section of Malletts Creek is most visible along Washtenaw Avenue, where crews have cleared 3 acres in order to create a natural storm water detention system called a wet meadow. This part of the project is west of the Meri Lou Murray Recreation Center and south of the Washtenaw Avenue bike path, within County Farm Park.
“The wet meadow has native vegetation. It's designed to store the water when it rains, hold it and release it slowly into the creek,” said Harry Sheehan, the environmental manager for Janis Bobrin, Washtenaw County’s water resources commissioner.
Workers have removed a handful of cottonwood trees and lots of woody shrubs, like the invasive species buckthorn, Sheehan said.
Crews will create a depression that will house native species and act like a slowly draining bath tub when it rains.
For drivers, the wet meadow portion of the restoration project means that a few hundred feet along Washtenaw Avenue could be closed for short periods of time through Dec. 1, when the brunt of the work on the wet meadow will be done. The lane closures will occur as crews move equipment in and out of the site on a temporary driveway. When the project is complete, the driveway will become a pathway that connects the Washtenaw Avenue bike path to County Farm Park.
Photo courtesy of the office of Water Resources Commissioner Janis Bobrin
Branches of Malletts Creek run above ground or in underground pipes in the Burns Park neighborhood, around Briarwood Mall and at the Ann Arbor Municipal Airport. The branches merge at Stone School and Eisenhower Parkway near Malletts Creek Branch of the Ann Arbor Public Library. The creek empties into South Pond and the Huron River, near Gallup Park.
The creek’s 11-square-mile, pavement heavy floodplain overloads the waterway, which causes erosion, Sheehan said. The erosion means sediments clog the creek, hurting aquatic species at the bottom of the food chain.
To help address the problem, workers are restoring the shoreline along the 1.5- mile section of the creek, Sheehan said. The creek’s sometimes-steep banks will be regraded, shored up with stones and planted with native species to help control harmful erosion.
Besides sediment from creek beds, phosphorus also washes into the creek. The environmental impact includes algae blooms in Ford and Bellville lakes that can kill fish and harm recreation, Sheehan said. Pollutants like oils, E. coli and heavy metals that wash from city surfaces directly into the creek pollute the Huron River every time it rains.
The project is funded by a combination of low-interest loans and grants from he Michigan Department of Environmental Quality’s green infrastructure program, Sheehan said.
The most recent project is part of a plan developed by the City of Ann Arbor and the Office of the Water Resources Commissioner in 2000 to improve the flow and quality of water in Malletts Creek with MDEQ-funded projects like this one.
Another recent result of the partnership is a wetland in Mary Beth Doyle Park completed in 2008 that can hold 15 million gallons of stormwater before releasing it into Malletts Creek.
Planners estimate the current project will prevent 685 tons of erosion annually and cut the amount of phosphorus entering the river by 15 percent each year.
- Download a pdf of the Malletts Creek streambank stabilization project..