HVA is checking out culverts in Washington and Roxbury to determine which ones are barriers to fish and wildlife movement, and those that would fail during a flood – causing damage to roadways by allowing water to flow over them.
To survive, fish and other aquatic life along with animals that live on river banks, such as muskrat, mink, otter, frogs, stream salamanders, turtles and snakes, need to move freely through rivers and streams to access habitats, avoid adverse conditions, and seek food and mates.
Having surveyed thousands of culverts and bridges in the Housatonic watershed, HVA has concluded that more than half of them are undersized and prone to blockage, and many are in disrepair. In addition to being barriers to fish and wildlife, they are a hazard for the traveling public, and can interfere with emergency response during flood events. They are also expensive for municipalities and the state to maintain.
“The good news is that the same design principles that ensure safe passage for fish and wildlife make for safer, more resilient crossings that require less maintenance,” said Mike Jastremski, HVA Watershed Conservation Director. “Fixing these problematic crossings is a real win-win for communities and the environment.”
HVA Executive Director Lynn Werner adds, “HVA launched this initiative in the Berkshires several years ago. We partnered with the Berkshire Environmental Action Team and trained an army of volunteers who have collectively examined more than one thousand stream-crossing culverts so far.”
HVA has identified 58% percent of non-bridge road stream crossings as “moderate or worse” barriers for fish and wildlife movement. A flood risk study conducted by HVA’s partners at the University of Connecticut indicates that 27 percent of non-bridge road stream crossings would fail during floods expected to occur regularly (the 25-year recurrence interval flood or larger).
According to Jastremski, a good crossing spans the stream and banks, does not change water velocity, has a natural streambed and creates no noticeable change in the river. He said that effective crossings include bridges, open bottom arches and culverts that span and are sunk into the streambed. Good culverts also make it easier for animals to avoid roads and the direct threat of being struck and killed by a vehicle. They also lessen the danger of people being injured when they try to avoid hitting an animal on the road.
The project was expanded into Northwest Connecticut in 2015 in the towns of Canaan, Colebrook, Cornwall, Kent, Norfolk, Salisbury, and Sharon. This spring and summer it’s being replicated in the watershed towns of Oxford, Seymour, Washington, and Roxbury, as well as Dover, New York.
This project helps communities identify highest-priority replacement projects based on conservation value, flood risk and maintenance need, encourages adoption of culvert design Best Management Practices, and seeks ways to finance replacement projects.
Funders for this project include Connecticut Community Foundation; the Northwest Connecticut Community Foundation; Housatonic River Natural Resource Damages Fund; National Fish and Wildlife Foundation’s New England Forests and Rivers Fund; Patagonia World Trout Initiative; Farmington River Coordinating Committee; and the Connecticut Institute for Resilience and Climate Adaptation.
HVA is partnering with the towns, UCONN Civil and Environmental Engineering Department, Princeton Hydro LLC, Connecticut Department of Energy and Environmental Protection-Inland Fisheries, Trout Unlimited, Aton Forest, North Atlantic Aquatic Connectivity Collaborative and Farmington River Watershed Association.