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Written by ncclass
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Friday, 21 November 2008 |
The Problems at Road Stream Crossings
When roads were first built in the region, we focused on one thing: getting cars and trucks across the stream. We didn’t think about the effects that crossings have on our streams and fish. With over 1,000 road stream crossings in the Bad River Watershed, the cumulative effects of these crossings on our streams and fish are significant.
We’ve learned recently that culverts can pose two major problems in the watershed.
Fish passage problems:
Culverts can act as barriers to fish by blocking access to quality habitat upstream. There may be a drop at the outlet that prevents fish from getting into the pipe. Or the water velocity in the culvert may be too fast for fish to make it all the way through the pipe.
Sedimentation Problems:
Road crossings can also have a negative affect on our streams by adding sediment into our stream channels. Extra sediment can come from a road failure, or from a regularly eroding stream crossing. This extra sediment covers the stream bottom, filling in spaces for insects which are the food for fish, and also limits spawning success.
The Solution at Road Stream Crossings
BRWA’s Culvert Program works to prevent both fish passage and sedimentation problems. The goal of our culvert replacement is to allow fish to move through the pipe by removing an outlet drop and slowing the flow of water in the pipe. Often this means buying a bigger pipe, and setting it lower in the stream. That way we can maintain the connection between below and above the crossing for fish.
In addition, BRWA’s fish friendly culvert design can increases the life of the culvert, and reduce road problems for town road crews.
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Last Updated ( Friday, 19 December 2008 )
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Culvert Program 
