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| In Vermont, many species of fish and wildlife inhabit streams, wetlands and adjacent riparian lands. For reasons as simple as the need to escape extreme floods or as complex as maintaining genetic diversity, animals living in or along streams need to be able to move unimpeded through the watershed. Think about the roads you drive on every day. What if these roads were suddenly and permanently blocked so that you could not get to important places? This may sound absurd, but this is precisely the issue that faces species inhabiting streams throughout Vermont and elsewhere. Through the combined effects of dams and poorly designed stream crossings, we have blocked streams and forced fish and wildlife to cope with these restrictions. Many populations of stream-dependent species have been diminished or lost completely because of these barriers.
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| Impassable Culvert |
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| AOP Friendly Culvert Topsham, VT |
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In the past, stream continuity was not often considered in the design and construction of stream crossings. Many of Vermont’s existing stream crossings are barriers to movement of fish and wildlife. Some stream crossings that did not restrict passage when originally constructed have become barriers as the result of streambank erosion, stream channel changes or mechanical breakdown of the structure. A study conducted by the Vermont Fish & Wildlife Department (VFWD) of aquatic organism passage (AOP) through culverts provided some sobering results. Of 1,501 culverts surveyed between 2004 and 2007, less than six percent were found to provide full passage of aquatic organisms. View Chart of Results
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