Northam Rd Culvert Replacement in Shrewsbury, VT

The Northam Rd Culvert was an undersized (43% bankfull width) culvert that crosses Northam Rd just south of the (now removed) Mountain School Road Dam, which was removed in 2026. This culvert was replaced in order to restore geomorphic function, aquatic organism passage, and increase flood resilience along the Cold River. This culvert was undersized, restricting flow and contributing to roadway overtopping and erosion during high flow events. It was expected that with the removal of the upstream dam, these flow issues would be exacerbated. The undersized culvert limited sediment and wood transport, altering the proper geomorphic function of the stream, causing increased nutrient inputs from streambanks and improperly managing waterflow from forested lands. Upsizing this culvert to restore stream geomorphology improved proper stream sediment transport and reduced nutrient inputs from streambank and from forested lands by properly managing flows, as well as improving flood resilience, reducing likelihood of future road washout, and restoring aquatic organism passage.

This culvert was replaced in 2026, funded by the Town of Shrewsbury's VTRANS grant, town tax payer funds, and the Vermont Department of Environmental Conservation Clean Water Initiative Program through a grant administered by Watersheds United Vermont, awarded to RNRCD.