Implementing one of the largest restoration projects in the Great Lakes Area of Concern Program

Spirit Lake Restoration

Located in the St. Louis River Estuary in Duluth, Minnesota, Spirit Lake is the focus of one of the largest restoration projects to have been implemented in the Great Lakes Area of Concern Program. Between 2020 and 2024, the site underwent remediation and planting efforts to restore a combined 138 acres (56 hectares) of upland and aquatic habitat.

Our role on the project included upland restoration, erosion control, and invasive species treatment, in addition to the in-water installation of native plugs. We installed 342,000 aquatic plants in 2023 and another 20,000 in 2024. We are currently overseeing the monitoring phase of this effort.

To handle the volume of plants being delivered from Minnesota and Wisconsin nurseries, the project required a greenhouse to be constructed on-site. The space included holding areas for both submerged and emergent vegetation. A native plant specialist from our Walkerton, Indiana, nursery temporarily relocated to the project site to manage the deliveries, growth, maintenance, and tracking of plugs. Our team worked closely to execute the design while working with small plants in a dynamic system with large water level fluctuations.

Three aquatic monitoring events are planned, with one having been completed to date. As part of this, we’re surveying submerged aquatic native and invasive species and emergent species along the shoreline, following Minnesota Department of Natural Resources (MNDNR) Aquatic Plant Monitoring protocols.