fish ladder

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fish ladder

[′fish ‚lad·ər]
(civil engineering)
Contrivance that carries water around a dam through a series of stepped baffles or boxes and thus facilitates the migration of fish. Also known as fishway.
References in periodicals archive ?
WATER SOLUTION Whooshh Innovations, based in Washington state, says its Passage Portal is a much better way to go than fish ladders
Simultaneously, automatic listening stations Lotek SRX-400[R] with directional antennas were deployed close to fish ladders to monitor fish movements in different parts of fish ladders.
In 1997, the Federal Energy Regulatory Commission refused to relicense the Edwards Dam without the expensive construction of fish ladders, leading the dam's owner to choose removal as the cheaper and more fish-friendly option.
Today, over 1,500 linear feet of stream channel and its floodplain has been reconstructed, a 36-foot span bridge has been installed, two fish ladders have been removed, and over two acres of estuary have been re-established to the benefit of Pacific Northwest salmon and resident Puget Sound species.
Fish ladders were another action taken by the Sector.
For example, the Horseshoe Bend Boat Chute and Fish Ladder was designed by MWE and completed in 1995.
Fish ladders have been constructed on some of the dams to help them over these impasses, but many juvenile fish die in them.
Savage Rapids' poorly designed fish ladders block salmon returning from the ocean meaning the fish can stray into irrigation canals and turbines.
Two years ago, a draft environmental study concluded that the dam could stay if its owner, Edwards Manufacturing Company, added expensive fish ladders. But FERC reversed its position after new studies concluded that installing fishways would do little to help four species of fish and would cost about $10 million - almost double the cost of removing the dam.
Examples of restoration projects would include the removal of invasive, non-native plants from wetlands and forests, restoration of tidal flushing to marshes, planting beach grass on trampled dunes, and providing passage through or around a barrier such as is achieved by the installation of fish ladders at dams.
Many salmon runs were squelched outright by high dams like Grand Coulee) that lacked fish ladders and thus closed off thousands of river miles to migrating salmon.
Like anything associated with fishing, there's an element of exaggeration to Gillam's claims: This year's run is late, and the only can't-miss fishermen are the grizzly bears perched atop "fish ladders," five- to six-foot mini-waterfalls where they snare in their jaws salmon leaping against the current.