Demonstration projects showcase specific road stream crossing retrofits/replacements. Here are two examples from Massachusetts:
Bronson Brook Habitat Restoration, Worthington: A concrete double box culvert was replaced by an open bottom arch.
Tower Brook Continuity Pilot: A perched culvert on Tower Brook, a tributary of the Wild and Scenic Westfield River, was improved to allow fish passage.
Churchill Brook: In 2018 the City of Pittsfield replaced a stream crossing on Churchill Brook, a coldwater fish resource and productive trout stream. This crossing had been identified as a “severe barrier”. The Housatonic Valley Association, partnering with the Berkshire Environmental Action Team and the City of Pittsfield, coordinated the replacement which was funded by the Natural Resources Damages Fund and the City of Pittsfiel.. With funding from the Massachusetts Environmental Trust, HVA coordinated the installation of two rain gardens adjacent to the new crossing. These rain gardens have already prevented many pounds of sediment from reaching the brook!