The Stormwater Wetland in the City of Readlyn is a great example of a small community working to do their part in improving water quality. Also called the Readlyn Wetland, it provides a direct benefit and ecological uplift to the downstream agricultural communities and future generations.
The stormwater wetland idea was started because of available funding through the Clean Water State Revolving Fund (CWSRF). The City of Readlyn was undertaking a needed overhaul to its sewer treatment plant. The treatment plant project was financed with a loan from the CWSRF, which provided the City with an opportunity to participate in the Water Resource Restoration Sponsored Project funding. The City was interested in leveraging their investment in the treatment plant and the sponsored project funding was a great opportunity.
A stormwater wetland was chosen as that project. It captures stormwater runoff from over half of the City. As runoff travels through the wetland, it undergoes a decrease of nutrients, pollutant, and peak flowrates. The location identified for the wetland was a historically wet and low producing agricultural field on the south edge of town. The City worked with the private property owner to acquire the land so the wetland could be constructed.
The wetland features a sediment removal forebay and a 1.9-acre permanent pool with high marsh, low marsh, and pool microtopography. The wetland features 1,500 linear feet of meandered flow path. A planned maintenance path around the wetland will double as a public walking trail for recreational access. When complete, the project will provide treatment for 144,000 cubic feet of runoff from a 95-acre watershed. Anticipated nitrogen reduction is 30% or greater. Phosphorus reduction for a stormwater wetland is estimated at 15%-45%. The expected suspended solids reduction provided by the wetland is 50%-80%.
The buffer around the wetland will be planted with native wet prairie mix. School classes have already started education on wetlands and the local school received a grant award to plant plugs along the edge of the wetland in the spring of 2020. The wetland will serve as a location for field trips and other educational programming in the future.
Additionally, the wetland is adjacent to the trailhead for the Rolling Prairie Trail where trail users can stop for a walk. An important element of the project is the outreach presentations to the Upper Wapsipinicon Watershed Management Authority and the local school.