Barker's Island Site Improvements Project
This project is a big undertaking for the City! Please be patient and keep in mind that the project outcomes will include connecting trails, more trees, green infrastructure, and better accessibility to the water. Frequent updates will be posted to the City of Superior's Facebook pages as we traverse the different phases of construction.
Construction start date: April 11, 2022
Projected end date: September 2022
Location: Barker's Island, Superior, WI
Grant funding is provided by the National Fish and Wildlife Foundation (NFWF): Sustain Our Great Lakes (SOGL).
The City of Superior was awarded a National Fish and Wildlife Foundation (NFWF) grant. The main objective of the NFWF project is to install green infrastructure elements by decreasing impervious surfaces and increasing vegetation.
A Greener Barker’s Island
The National Fish and Wildlife Foundation grant funded project directly complement several other projects on Barker’s Island. These projects on Barker’s Island incorporate green infrastructure practices.
What is green infrastructure?
Green infrastructure projects involves stormwater best management practices (BMPs) designed to control flooding, reduce erosion, and improve water quality.
Projects that install stormwater BMPs have proven effective at reducing Total Suspended Solids (TSS) and excess nutrients going into surface waters, and increasing stormwater storage. For example, the bioinfiltration basins installed in the parking lot adjacent to Barker’s Island Inn, allow for treatment through a variety of physical, chemical, and biological processes before the water returns to the estuary.
Why slow the flow of stormwater?
Parking lots, sidewalks, and paved roads are great examples of impervious surfaces; water cannot infiltrate into the surface rather stormwater runs off. On Barker’s Island, runoff flows from impervious surfaces directly to the St. Louis River Estuary (in Ojibwe, Wekwaa-gichigamiziibi or “end of the lake river”) and eventually to Lake Superior (in Ojibwe, Gichigami or “a sea, or large lake”); our drinking water source.
Below is a cross-section illustration showing what an installation of permeable pavers looks like. Notice the spaces between the permeable pavers. These spaces allow for stormwater to seep through, which reduces stormwater runoff and in turn helps to prevent surface water pollution. Permeable pavers help to slow the flow of stormwater into our waterways.
Why native plants?
The National Fish and Wildlife Foundation (NFWF) grant funded project included native plantings along with a porous asphalt trail (cross-section illustration pictured below). Native plants provide a number of benefits for pollinators and the trail helps increase stormwater infiltration. Traditionally, lawns are composed of turf grass. A commonly used type of turf grass is Kentucky Bluegrass, which is a non-native species.
Unlike turf grass, native plants have long roots (pictured below), which increase the amount of stormwater that soaks into the soil and helps them survive droughts.
What are bioinfiltration basins?
Bioinfiltration basins and wet ponds are types of stormwater best management practices (BMPs). These basins are built to retain and redirect stormwater to the wet pond to continue the treatment process. These stormwater BMPs are planted with native species to help stabilize the soil and will also provide habitat for wildlife.
How does stormwater move through the basins?
- Stormwater infiltrates through the mulch and soil, where it is treated by a variety of physical, chemical, and biological processes before it percolates into the soil.
- As the basins fill up during rain events, the overflow structure will discharge water to the wet pond; regulating the maximum ponding depth of the basins.
- Additionally, the underdrain pipe will direct water to the wet pond where more settling and biological treatment occurs prior to returning to the estuary.