Bears - Sounds Wild
Tree Marks

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Fish Passage

On a beautiful summer day in Southcentral Alaska, a track hoe is at work on a road crossing a salmon stream. A crew is replacing the three very undersized and damaged culverts with a far superior stream simulation culvert. A stream-simulation culvert is as wide as or wider than the creek and either bottomless or embedded below the stream bed. A stream bed is built through the culvert that is similar to the natural stream bed. Most stream simulation culverts have stream "banks" on either side of the stream made of rock that accommodate high flows and allow small animals to move through the culvert. The end result looks more like a bridge than a culvert.

Undersized culverts are barriers to fish. They concentrate the speed and flow of water. This often means the water in the culvert is too fast for fish to swim against. Over time, the concentrated flow coming out of the culvert will wash away the bed of the stream and the culvert will become perched above the stream bed.

Many culverts that are barriers to fish are also prone to plugging with debris during floods, creating problems for maintenance crews. Replacing a road crossing that poses a problem for fish and public safety a win-win situation.

In recent years Fish and Game and partners like the US Fish and Wildlife Service and local boroughs, have replaced or removed 38 barrier crossings, providing unimpeded access to more 95 miles of stream habitat and thousands of acres of lakes.