Wetland park is a natural water filter

A new stormwater device will use thousands of grasses and blooming plants to clean water flowing through the center of Wilson in Hominy Creek.

The Park-Mercer Flow-Through Wetland, a 62,934-square-foot project, is under construction by the city of Wilson at the corner of Park and Mercer streets.

The N.C. Department of Environmental Quality funded a grant to build the stormwater and channel retrofits for the upper portion of Hominy Creek.

The N.C. State University Department of Biological and Agricultural Engineering designed the project, which pumps water out of the creek and allows gravity to move it through a channel with five deep ponds.

Some 50,000 plants will be placed in and around the device.

The plants include yellow pond lily, white waterlily, American bur-reed, broadleaf arrowhead, lizard’s tail, iris Virginica, common rush, yellow canna, sweet flag, marsh hibiscus, swamp milkweed, scarlet rosemallow, eastern bluestar, goldenrod, New Jersey tea, aromatic aster and tickseed.

Some 79 pounds of fescue and 23 pounds of annual rye grasses will cover the remaining ground.

“I think there are plugs going in anywhere from a 1-inch plug to gallon-sized pots,” said Davis Jones,  a corrective regional manager with Dragonfly Pond Works. “They will be placed based on where they are going to thrive. We will have water plants that will be in through the channel. We will have marsh plants that are going to be in the flat area that represent a marshy area, and then we will have grasses and everything stabilizing the slopes.”

The project has a series of deep pools that are guided through a marshy area with a channel through the entirety.

Jones said the device’s design is cutting-edge.

“This is one of the few devices that has been built like this,” he said. “I think there are maybe five to 10 max of devices of this type in the entire country, so this is something that is new for us.

“This is like the first one that N.C. State has designed of this type,” Jones added. “We do wetlands, wet ponds and bio retentions all the time, but this is kind of a unique one.”

This stormwater device will pull toxins out of the water, getting rid of oil, nitrogen and phosphorus.

“All the plants in the pond do that type of work,” Jones said.

The Dragonfly crew has used excavators to shape the channels and ponds.

“We are at the point where were are starting to do our fine grading,” Jones said.

Planting should begin by the end of May.

“Some of the plants that we are planting in here have really vibrant flowers,” Jones said. “One of our favorite ones is pickerelweed. It has a big purple flower that is almost like a bushel of small flowers that make up a bigger flower. It will be great.”

A pump will regulate the water level in the device. The water will constantly move in and out, so it won’t be a home for mosquitoes.

Once in the ground and rooted, the plants will begin to thrive.

“It usually takes one to two years and it looks pretty good,” Jones said. “It starts to fill in, and by three to five years, it has completely taken off.”

The area should be buzzing with dragonflies after planting.

“Dragonflies eat up to 150 mosquito larvae a day. Overall, dragonflies are beneficial to the ponds themselves,” Jones said. “Pickerelweed is a very, very sweet-smelling flower, and it attracts dragonflies. All of your irises, your sweet flag, your blue flag, those types of irises attract dragonflies as well. There will be a lot of them out here.”

Jones said a future plan involves adding a walking path and walking bridge across a section of the device.

For more information, visit the construction site, where the city has placed an artist rendering of the device plus six large placards that explain what is being constructed.

The post Wetland park is a natural water filter first appeared on Restoration NewsMedia .