Kawkawlin River Shoal: Supporting Coastal Resilience

Site: Kawkawlin River Mouth

Project: Build 0.75-acre nearshore fish spawning reef north of river mouth

  • Primary focus: Decrease frequency of dredging
  • Secondary focus: Increase diversity of fish habitat

Project status (as of March 2024): Feasibility and outreach

Why here?

  • Sedimentation at the Kawkawlin River mouth requires regular dredging to keep the channel open and safe for boats.
  • Modeling shows a strategically placed reef could reduce the amount of sediment entering the recreational navigational channel, reducing long-term dredging costs.
  • Reef could help reduce shoreline impact from exposure to wind and waves.
  • Structure would have a low risk of getting covered by sediment.
  • Healthy fish populations and diverse habitats are key to a strong, resilient Saginaw Bay
  • Site was identified through bottom mapping, sediment sampling, and computer models of wind, wave, and sediment movement.
  • Reef would promote successful spawning for multiple native fish species.


  • Pursue opportunities that incorporate coastal resilience and fish habitat needs.
  • Provide shoreline communities with protection and buffering from the impacts of flooding, erosion, and coastal habitat loss.
  • Improve habitats for fish and wildlife species for Saginaw Bay.
  • Work with communities to generate shared vision, support, and buy-in.


  • 2020-2022: MDNR and ECT Inc. developed an initial feasibility report exploring several additional reef restoration sites in Saginaw Bay to address coastal resiliency and restoration of critical reef habitat for fish and wildlife with funding from NFWF.
  • 2022: MDNR and the Great Lakes Fishery Commission (GLFC) received funding through a NOAA Regional Partnership to advance additional feasibility, engineering/design, and construction studies for options identified through the feasibility study.
  • 2023: Partners hosted a community workshop to gather input from local stakeholders.
  • 2024: Based on input gathered from local stakeholders, GLFC, MDNR, EGLE, ECT Inc., and Purdue University continued to gather and refine feasibility information for the Spoils Island and Kawkawlin River restoration sites.


How does dredging currently affect nearby communities?

This information is currently being collected and will be added here as it becomes available.

Will boating navigation at the Kawkawlin mouth be affected?

It is possible that the reef may pose a navigation risk to deep draft vessels when the bay is at low water conditions. Information is being gathered to understand exactly how far under the water surface the reef may be under different water levels. If constructed, the reef will be marked for navigation similar to how the mouth of the Kawkawlin River is currently marked.

Will current beaches be affected by the Kawkawlin River mouth sediment reef?

Additional information is being gathered to estimate the changes in deposition patterns down-drift from sediments deflected by the reef as identified in the stakeholder workshop.

Will the need to dredge be reduced at the Kawkawlin River mouth?

Project partners are continuing to build and refine models to estimate the potential changes in sediment deposit and the subsequent changes to dredging frequency.

Will there be obstructions to using the beaches?

Additional feasibility work will determine all measurable impacts. No restrictions to beach use are anticipated.

Who will pay for these projects?

A variety of grant funds from the National Fish and Wildlife Foundation– Coastal Resilience Program, the National Oceanic and Atmospheric Administration, and the Dow Chemical Natural Resources Damage Assessment will be used to fund feasibility studies and construction of feasible options.

Who is working on these projects?

Michigan Department of Natural Resources (MDNR), Michigan Department of Environment, Great Lakes, and Energy (EGLE), Great Lakes Fishery Commission (GLFC), NOAA, ECT Inc., LimnoTech, and Purdue University.

Where can I get more information about these projects?

The Great Lakes Fishery Commission has additional details about several Saginaw Bay restoration projects.