Swan Lake National Wildlife Refuge Mitigation Project – Hydraulic Modeling
Type of work: Water and Environmental,
To help offset environmental impacts from the proposed 2,350-acre Roy Blunt Reservoir, Allstate Consultants led hydraulic modeling and design for major restoration work at Swan Lake National Wildlife Refuge (SLNWR). Efforts were focused on restoring natural water flow and improving wetland habitat across much of the 17-square-mile refuge.
Key improvements will include:
- Removing five miles of levees to reconnect 0.74 square miles of historic floodplain along Yellow Creek.
- Lowering four miles of levees by 4–6 feet to allow natural flood movement across 4.5 square miles of wetland areas.
- Expanding and building new spillways to improve flow between the Grand River, Yellow Creek, Silver Lake, and Swan Lake Marsh.
- Upgrading or adding 10+ water control structures to better manage wetland levels.
Allstate developed and ran advanced hydrologic and hydraulic models to:
- Estimate ecological benefits across 8,251 acres of habitat,
- Provide critical design data for the restoration,
- Ensure no negative impacts to surrounding areas.
Allstate’s work included a 2D HEC-RAS model of the entire refuge and Grand River floodplain, continuous water simulations for key marshes, and detailed flow analysis using integrated SWMM-based modeling.