American Crane and Equipment Corporation completes jib dam project
6 May 2015American Crane has designed and manufactured two 5-ton jib cranes to help lift salmon across dams in Washington State.
The cranes that feature corrosion resistant components to safely operate in an outdoor aquatic environment.
All of its gearing, which include the drive motions and gear rack, was designed with a minimum service factor of 2.0 for heavy-duty service.
American Crane was called upon for the project after Tacoma Power re-licensed Cushman Dams 1 and 2, with the Washington Department of Natural Resources mandating the restoration of the spawning migration for salmon living in the lake.
"Once the fingerling size salmon are old enough, they instinctively swim downstream to the ocean where they live for three years. After that period, the mature salmon swim back up the same stream to Lake Cushman to spawn in the water where they were born. But since both dams block the salmon's path up and downstream, they need some help getting around these barriers," the company explained.
Tacoma Power installed fish collectors at the top of Cushman Dam one, which is located directly on Lake Cushman and at the base of Cushman Dam two, which is located on the North Fork Skokomish River).
It added: "The fish collectors are floating platforms that funnel the fish into holding tanks for transport. The collectors capture the young fingerlings and adult salmon for later release into the North Fork Skokomish River and Lake Cushman respectively.
American Crane's Jib Cranes were leveraged to help the salmon to the first part of their journey with the cranes aiding in transporting the salmon from Lake Cushman into the North Fork Skokomish River, past both dams, where they head out to sea.
The first Jib Crane has a 36 foot hook reach, which lifts each 6' x 3' x 4' 9000 pound tank out of the Lake Cushman collector facility, and places the tank atop Dam one onto a battery powered cart.
Following this, the cart moves the tank off of Dam one and then moves it adjacent to Jib Crane two, which is equipped with a 13 foot hook reach. The second crane lifts the tank onto a truck, which then transports and releases the salmon into the North Fork of the Skokomish River below Cushman Dam two.
