In 2010, culverts were replaced on Bride Brook in Connecticut. With the increased flow from the new, larger culvert, fish were able to swim upstream for the first time in more than a decade.
Culverts, which allow water to flow under roads and bridges, are everywhere. Culverts sometimes block fish from swimming upstream. Many old culverts are much more narrow than the streams that channel through them, and sometimes too high for fish to jump through. When this happens, fish can’t reach their spawning habitat upstream of the culvert.
The herring run on Bride Brook is the second largest in the state. In the 1970s, it was as high as 175,000 per year. But the culverts had reduced the run to less than half that number.
With tidal flows restored, adult river herring now have access upstream to Bride Lake to spawn, and juveniles can swim downstream to feed and grow in the ocean. Approximately 275,000 fish passed through the new culvert during the spring of 2012; more than triple what had seen in recent years.
A Similar project will replace tide gates on the West River in New Haven Connecticut. The improved tide gates will allow a more natural flow of water and improve fish passage.
source: NOAA FishNews