Aerial view of the St. Louis River Estuary.
The St. Louis River Estuary is the confluence of the St. Louis River with Lake Superior; to the west is Duluth, and to the east is its twin port city, Superior, Wisconsin. At 12,000 acres, the St. Louis River Estuary is the largest freshwater estuary in North America and is the headwaters of the Great Lakes.
In estuaries, water flow and the natural movement of sediments combine to provide unique, productive, shallow water habitats. Over the past 100 years, a legacy of historic commercial uses of the estuary disrupted and altered these natural habitats as shorelines and near shore areas were dredged and developed, and chemical contamination impacted the waters.
Restoration and remediation projectsThis interactive story map describes the SLRAOC habitat restoration projects in Minnesota and Wisconsin, as well as the remediation projects located in Minnesota.
People recognized that legacy sediment contaminants needed to be remediated and damaged habitat needed to be restored. The St. Louis River Estuary was designated an international "Area of Concern" and a partnership of federal, state and tribal agencies is working together to restore the estuary.
The Minnesota Department of Natural Resources (DNR) is leading habitat restoration projects in the estuary intended to address harm to fish and wildlife populations and restore fish and wildlife habitat. The DNR and its partners have identified ecological targets to guide selection, design, construction, and monitoring of projects. These targets set goals for increasing diversity and area of wetlands, restoring aquatic vegetation, softening shorelines, increasing riparian connectivity, improving benthic macroinvertebrate communities, and reducing sediment loads.
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- Kingsbury Creek Watershed
An eroding bank on 68th Avenue West Creek that will be stabilized during construction.
MNDNR recently completed the restoration of Kingsbury Bay, an 80-acre shallow bay in the St. Louis River estuary that had received excessive sediment inputs from Kingsbury Creek & 68th Ave W Creek. Decades of sediment accumulation filled the bay’s open water wetlands, converting them to shallow stands of non-native cattail. MNDNR began restoring Kingsbury Bay in 2019 by dredging sediments to create open water and wetlands supporting native plants. Restoration of Kingsbury Bay is an element of the Natural Resource Damage Assessment (NRDA) settlement for the St. Louis River Interlake/Duluth Tar Superfund Site (SLRIDT). In order to increase the resiliency of this restoration work, the Trustees for the NRDA process consider it important to also address the underlying causes of excessive sedimentation in the Kingsbury Creek watershed.
Working on behalf of the Trustees, MNDNR began a process to assess the Kingsbury Creek watershed and select one or more projects to reduce future sediment loading in the creek, while also considering the ecological functions and biological habitat of the stream system. In 2019, Barr Engineering Co. completed a feasibility study of the Kingsbury Creek watershed. They identified stream reaches and watershed areas that are contributing excessive sediment and recommended conceptual plans for restoration or stabilization of these areas. In 2020, the NRDA Trustees worked with MNDNR and a team of local resource managers to review the feasibility study and select one or more projects to implement with current funding. Several project locations were chosen along 68th Ave W Creek and an unnamed tributary to Kingsbury Creek. Barr Engineering Co. completed the final plans and specifications for the project in 2021 and is now acquiring the necessary permits. Construction is anticipated to begin in late 2022 or 2023. The work will be funded through the SLRIDT NRDA settlement and the MN Outdoor Heritage Fund.
- Manoomin (Wild Rice)
Left: Manoomin flowering. Upper right: Manoomin floating on top of water. Lower right: Exclosures to protect emerging plants.
The St. Louis River estuary is the largest coastal freshwater wetland ecosystem on Lake Superior and is the most significant source of biological productivity for the western half of the lake, providing critical habitat for fish and wildlife communities. Historically, wild rice grew in abundance in shallow embayments and backwater areas of the St. Louis River estuary below Fond du Lac. Wild rice beds, which are a vital component of the river’s ecosystem, supply valuable wildlife habitat, improve water quality, and serve as a culturally significant source of food for human communities in this area. Wild rice beds provide valuable cover, food, and loafing sites for numerous bird species of conservation concern. They supply one of the most important waterfowl foods in North America largely because the maturation of wild rice seed coincides with fall migration. Rice beds also provide nursery areas for small fish, frogs, and other aquatic prey for common loons, great blue herons, and other piscivorous bird species.
The goal of the project is to increase the abundance and distribution of self-sustaining wild rice within the St. Louis River estuary, to increase opportunities for culturally significant rice harvest and to benefit fish and wildlife species. This includes contributing to the removal of the Loss of Fish and Wildlife Habitat impairment within the St. Louis River Area of Concern. To achieve this goal, the project partners plan to restore or enhance wild rice beds where habitat conditions are suitable and provide opportunities for harvest.
Wild rice restoration in the St. Louis River involves site preparation, seed collection, seeding, construction and maintenance of exclosures and monitoring of restoration success.
- Mud Lake
Opening in railroad causeway. Photo credit: MNDNR
Looking south over the railroad causeway bisecting Mud Lake. Photo credit: Sam Geer
The Minnesota DNR is working to restore fish and wildlife habitat at Mud Lake, a sheltered bay of the St. Louis River that is bisected by a railroad causeway. There is only one causeway opening that allows water to flow between the two sides, which limits the hydrologic connection of the west side to the estuary. The project goals are to restore deep water habitat, reestablish native wetland plants, and improve the flow of nutrients and sediment between both sides of Mud Lake and the St. Louis River.
This work is part of a greater effort by many local, state, and federal agencies to mitigate historic impacts to habitat in the St. Louis River under the Great Lakes Area of Concern Program. The MNDNR is working with the United States Army Corps of Engineers to design a project that will meet our goals and safely address any legacy contaminants found on site. Additional baseline sampling is occurring in the summer of 2022 to determine the composition and contaminant concentration of sediments that make up the lake bottom. The project design process will start in 2022 and continue through 2023. Project construction is anticipated to begin in 2024.
The project is estimated to cost $12 million and is being supported by the following:
Great Lakes Restoration Initiative, administered by the U.S. Environmental Protection Agency MN Outdoor Heritage Fund
- Perch Lake
Perch Lake restoration aerial view.
Minnesota DNR and the Minnesota Land Trust are working together to restore fish and wildlife habitat at Perch Lake. This work is part of a greater effort to mitigate historic impacts to habitat in the St. Louis River under the Great Lakes Area of Concern Program. Perch Lake was once a bay of the St. Louis River estuary. The construction of a railroad causeway and U.S. Highway 23 nearly eliminated this connection, drastically reducing the flows that flushed sediment from the lake and returned nutrients to it. The goal is to restore deep water habitat and improve flows between the Lake and the St. Louis River estuary.
Some of the baseline data needed to inform the designs of this project were collected in summer 2020 and required gathering sediment from Perch Lake and geological information from the highway crossing.
We worked with the United States Army Corps of Engineers to design phase one of this project. This phase is designed to remove sediment and organic material that has accumulated in Perch Lake, along with adding some fish spawning habitat and diversifying the wetland habitat by adding some hemi-marsh features. Implementation of this phase of the project began in July 2022 and will continue through approximately March of 2023.
We are currently working with a private consultant (SEH) to design phase two of this project. Phase two will improve the connection between Perch Lake and the St. Louis River estuary by installing 12 foot by 16 foot culverts under U.S. Highway 23 and the old railroad causeway (currently a section of the Waabizheshikana (Marten) Trail). Construction of phase 2 is anticipated to be begin in August of 2023.
This project is estimated to cost $7,000,000 and is being supported by the following:
- Great Lakes Restoration Initiative, administered by the U.S. Environmental Protection Agency
- MN Outdoor Heritage Fund
- Chambers Grove
Hardened shoreline at Chambers Grove (left), restored shoreline (right).
Chambers Grove Park is located on the upper end of the estuary near Duluth’s Fond du Lac neighborhood. This is a critical spawning area for Lake Superior’s migratory fish species including lake sturgeon, walleye, and longnose sucker, as well as resident species such as smallmouth bass and white sucker. The city park was built adjacent to the river in the 1960s and the shoreline was stabilized with a wall of steel sheet piling and a wooden boardwalk. Prior to restoration, the area lacked spawning habitat for lake sturgeon and the wall along the shoreline eliminated the shallow, slow-moving water important as fish rearing habitat.
Restoration included building instream rock riffles to establish spawning habitat for fish and creating a natural shoreline. The project also improved recreational access for fishing, canoeing, kayaking, and established ADA-compliant fishing platforms in several locations along shoreline. The DNR completed the project in 2015 with funding from the National Oceanic and Atmospheric Administration through the Great Lakes Restoration Initiative and by Minnesota’s Outdoor Heritage Fund. Following habitat restoration, the City of Duluth has invested significantly in the park, adding amenities such as restrooms and a playground, a pavilion, and picnic areas. Parking and wayfinding signs were also upgraded.
- Interstate Island (Phase I)
Construction of Phase I restoration at Interstate Island in 2015.Photo credit: The Minnesota DNR via Northern Images
Formed in 1934 when the St. Louis River navigation channel was dredged, the Interstate Island Wildlife Management Area rests on the Minnesota-Wisconsin border and is co-managed by both states. The island is federally listed as critical habitat for piping plover. It is also one of only two nest sites in the Lake Superior watershed for common terns, a species listed as endangered in Wisconsin and threatened in Minnesota. In 2015, the DNR rebuilt the height of the island to restore the sandy, wind-swept habitat needed by these uncommon birds. Fencing and string grids were improved to protect terns from predators. The DNR wildlife managers continue to monitor the island for tern reproduction rates and signs of attempted nesting by plovers. The project prevented the loss of crucial nesting habitat during a time of extremely high water levels in the St. Louis River Estuary and Lake Superior; it was funded by the US Fish and Wildlife Service and Minnesota’s Outdoor Heritage Fund.
The DNR and the Minnesota Land Trust have secured additional funding to implement Phase II restoration. They will completely repair the island from damage due to continued high water and ensure its long-term viability as a key nesting site for colonial waterbirds. Designs are underway and construction is estimated to be completed by November of 2020. The project will be funded by the Minnesota Outdoor Heritage Fund, NOAA, USFWS, and EPA.
- Interstate Island (Phase 2)
Restoration in progress; in the foreground, previously flooded portions of the island have been elevated and restored, the nesting area rebuilt, and new fencing installed. In the background, the island footprint is being expanded using sand from annual navigation channel dredging.
As the St. Louis River estuary was developed into a shipping harbor, habitat needed to support Common Terns was lost. Ironically, material dredged to form the shipping channels was stockpiled to create Interstate Island, which became one of only two remaining Common Tern nesting sites in Lake Superior and is a designated state Wildlife Management Area. In recent years, the water level in Lake Superior has been rising causing inundation of the island, loss of nesting area, and more predation of terns by gulls. Common Terns are listed as Threatened in Minnesota and Endangered in Wisconsin. Restoring habitat for this important species is being done under the St. Louis River Area of Concern program to address legacy impacts to wildlife populations.
In 2015, MNDNR completed Phase 1 restoration to protect the Common Tern nesting area from rising waters. MNDNR worked in partnership with the Minnesota Land Trust, Wisconsin DNR, the University of Minnesota Duluth’s Natural Resources Research Institute, U.S. Fish and Wildlife Service, and the U.S. Army Corps of Engineers to further restore, protect, and enhance this critical habitat. Phase 2 kicked off in spring of 2020, and was completed in spring of 2021. During Phase 2, we increased the island’s elevation to eliminate flooding and enhanced the Common Tern nesting area with rock, sand, cobbles, driftwood, and new fencing. Clean harbor dredge materials were placed to expand the island’s footprint, creating additional habitat for gulls and migratory shore birds. Lastly, we created a long-term management plan to maintain the island as suitable Common Tern nesting habitat into the future. Though the project is considered substantially complete, plantings of native dune vegetation may occur in 2021 and 2022.
This $2,800,000 project was completed with support from the following:
- Harbor Maintenance Trust Fund
- Great Lakes Fish and Wildlife Restoration Act, administered by the U.S. Fish and Wildlife Service
- Great Lakes Restoration Initiative, administered by the National Oceanic and Atmospheric Administration, the U.S. Fish and Wildlife Service, and the U.S. Environmental Protection Agency
- MN Coastal Program
- MN Outdoor Heritage Fund
- Kingsbury Bay and Grassy Point
New Grassy Point island constructed using legacy milling waste from adjacent river bottom and clean fill excavated from Kingsbury Bay.
Kingsbury Bay and Grassy Point – construction updates
Grassy Point was home to two sawmills in the late 1800s and early 1900s. Large expanses of thick wood waste remain and continue to impair aquatic habitat. The DNR will restore Grassy Point by removing wood waste, deepening shallow areas, and constructing beneficial habitat features to create a shallow sheltered bay. This work will enhance aquatic plant beds and provide warm-water fish spawning areas along the Keene Creek channel.
A comparison of Kingsbury Bay after removing invasive vegetation and dredging decades of excess sediment.
At nearby Kingsbury Bay, excessive sediment deposits have reduced wetland quality by significantly shallowing the bay and supporting non-native cattails. Removing excess sediment will help establish a variety of native wetland plants, create more open-water habitat, and increase recreational opportunities. Clean sediment removed from Kingsbury Bay will be used at Grassy Point to restore areas where wood waste was removed. Kingsbury Bay was selected for restoration through the Natural Resource Damage Assessment (NRDA) settlement process for the St. Louis River Interlake/Duluth Tar Superfund site. Future work upstream in the Kingsbury Creek watershed aimed at reducing excessive sediment loads into the creek and bay has been selected for funding through NRDA.
Why is this project being done?
The DNR will restore degraded wetlands at Grassy Point and Kingsbury Bay. At Grassy Point, sawmill waste deposited in the late 1800s and early 1900s is being removed. At Kingsbury Bay, excessive sediments supporting non-native vegetation will be excavated. At both sites, the DNR will create shallow sheltered bays and restore valuable wetland habitat. This habitat restoration project is one of many projects taking place in the St. Louis River estuary that will help get it delisted as an Area of Concern.
How long will this project last?
The project began in June 2019 and is currently scheduled for completion fall 2021.
Where is the funding coming from?
This $18M project is being completed with funding from Great Lakes Restoration Initiative, Minnesota Outdoor Heritage Fund, and St. Louis River/Interlake/Duluth Tar Superfund Site Natural Resources Damage Assessment and Restoration settlement.
What kinds of wildlife will benefit from this restored habitat?
Restored wetlands will support native emergent, floating-leaved, and submergent vegetation which provide fish spawning and nursery areas and feeding and nesting habitat for water birds. Deeper open water areas benefit overwintering fish, and softened shorelines create a natural transition for amphibian and reptile movement.
How will the construction schedule impact my neighborhood?
Barges will be used to excavate and transport most of the materials involved in this project. Large dump trucks will be required to bring in sand/gravel, haul away non-native vegetation, and transport some sediment from Kingsbury Bay for restoration use at Grassy Point. Hauling will be short-term, and routes may impact the Irving neighborhood, Indian Point Campground, and Grand Avenue. Frequent construction updates will include the most current haul routes.
What recreational trails and facilities will be impacted by the construction?
The City’s trail at Grassy Point will be closed in 2021. Portions of the Western Waterfront Trail at Kingsbury Bay will be closed temporarily during the restoration project. While restoration is in progress at Kingsbury Bay, the Munger Trail parking lot on Pulaski St. may be closed to the public with signs directing users to temporary alternate parking areas.
How can I get regular updates about this project?
Check this website regularly and sign up for St. Louis River Area of Concern updates via GovDelivery.
A video update on the project.
- Northern News Now, September 12, 2022
Minnesota DNR celebrates large habitat restoration in Duluth
- WDIO, September 12, 2022
Restoration of Kingsbury Bay and Grassy Point celebration
- FOX 21, August 21, 2019
Arman Rahman - Grassy Point, Kingsbury Bay Restoration to Complete December 2020
- Star Tribune, August 19, 2019
Pam Louwagie - St. Louis River estuary restoration starts to bring species home
- Northern News Now, September 12, 2022
- Knowlton Creek Stream Restoration
Pre and post-construction of the main stem (left) and tributaries (right).
Knowlton Creek is a designated trout stream and tributary to the St. Louis River. Developments within its watershed and a major flash flood in 2012 resulted in severe damage to the stream channel and a large sediment deposit near Tallas Island. Although Knowlton Creek historically supported trout and water temperatures were suitable, trout had been missing from the stream.
The DNR worked with the Spirit Mountain Recreation Area (SMRA) and City of Cloquet to re-design water systems and reduce erosion impacts to the creek and its tributaries. The DNR also repaired 6,500 feet of degraded stream channel, restored 8 acres of wetlands, reduced sediment inputs to the St. Louis River Estuary, and re-established a naturally reproducing brook trout population by creating suitable habitat and removing barriers to fish migration. Completed in 2017, this project was designed through a partnership between the Clean Water Legacy fund and the US Army Corps of Engineers.
Funding for construction was provided by US Environmental Protection Agency, Minnesota’s Outdoor Heritage fund and the National Fish and Wildlife Foundation.
- Radio Tower Bay
Wood waste in Radio Tower Bay (left), the bay post-restoration (right).
Radio Tower Bay was the site of two sawmills in the late 1800s. A railroad line once crossed the river there on wooden pilings. Concrete foundations from abandoned radio towers are found in the bay. The sawmills dumped waste slab wood and sawdust directly into the water, greatly reducing the quality of underwater habitat for fish. The waste wood made the bay nearly inaccessible for recreation.
Phase I of the project removed the wooden pilings that once supported the railroad line. Phase II removed 115,000 cubic yards of the century-old wood waste and restored 30 acres of sheltered bay habitat. Sheltered bay habitat is considered the most biologically productive habitat in the estuary. The bay was restored to a depth of approximately five feet, allowing for aquatic plant regrowth, improved aquatic habitat, and better recreational boating access. The project was funded by National Oceanic and Atmospheric Administration through the Great Lakes Restoration Initiative and Minnesota’s Outdoor Heritage Fund.
- Minnesota Saint Louis River Area of Concern Habitat Restoration and Protection
- St. Louis River Area of Concern Remedial Action Plan
- Lake Superior Lakewide Action and Management Plans and Associated Reports
St. Louis River websites
- MN Pollution Control Agency: St. Louis River Area of Concern Resources
- WI Department of Natural Resources: St. Louis River Area of Concern
- St. Louis River Alliance: About the AOC
- EPA: Great Lakes Areas of Concern
- St. Louis River Estuary: the Stories and the Science