Sargent is removing the Gonic Dam and Gonic Sawmill Dam on the Cocheco River in Rochester, New Hampshire, as part of a long-planned effort to restore the river. The project includes removing approximately 2,000 cubic yards of contaminated sediment, constructing a new river channel, and replacing riverbed material with large and small stone to create a naturalized riverbed. Sargent also installed scour protection around existing 10-inch and 14-inch cast iron sewer pipes beneath the river and used cofferdams to manage water flow during construction. Work required careful coordination around changing river conditions, with dam removal and river restoration progressing through summer 2026.
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