Fishies, Flooding and NHDES funding: A resilient stream crossing replacement story

After the Patriot’s Day floods of 2007, the Emerald Acres Housing Cooperative in Barrington, N.H., knew they had a problem. The Oyster River had exceeded the capacity of the 9-foot culvert supporting the only road providing access to this 100-plus home community, preventing residents and emergency response resources from leaving or entering the neighborhood for nearly a week (see video footage of the severe flooding event).

What they perhaps did not know was that this culvert had also been restricting wildlife passage (American brook lamprey, American eel, Eastern brook trout and the Blanding’s turtle are known inhabitants of the Oyster River) and contributing to water quality degradation (the Oyster River is impaired for dissolved oxygen, which can be exacerbated by erosion associated with the undersized culvert). An emergency repair was made to restore the road access and Emerald Acres has been working to identify funding for a long-term fix ever since. 

In the fall of 2023, thanks to a partnership between The Nature Conservancy, Emerald Acres Cooperative and the nearby Sterling Realty, with funding from NHDES’ Critical Flood Risk Infrastructure Grant, Aquatic Resource Mitigation Fund and Watershed Assistance Grant programs (among others), the undersized culvert was replaced with a 50-foot bridge. According to The Nature Conservancy’s November 2023 publication on this project, it “was truly a local affair: engineering was done by Streamworks of Madbury, and the bridge was built and installed by Hansen Bridge LLC of Springfield, New Hampshire using locally sourced wood for the decking.” This replacement opens up 5 miles of fish and turtle habitat, reduces water quality degradation and prevents flooding during larger storm events.