For thousands of years salmon have traveled up the Yukon River to spawn; some traveling to the Yukon's headwaters near Whitehorse, Yukon Territory. The salmon lay eggs in the fresh water sand where they develop over winter before hatching the following spring. The salmon fry remain in fresh water for a year or two, after which they make their way to the salt water oceans to live to adulthood. Some of these adults return to the fresh water where they were hatched to spawn, and start the cycle over again.
In the late 1950's this cycle was disturbed when Northern Canada Power Commission built a hydroelectric facility and dam on the Yukon River in Whitehorse. In order to provide a means for the salmon to continue their migrations again, in 1959 the Whitehorse Rapids Fishway (commonly called the "fish ladder") was built.
This unique structure provided a "ladder" for the salmon to move from below the dam at the hydroelectric plant and go upstream to the spawning areas. An underwater canal directs the fish toward the ladder entrance. A series of steps with flowing water allows the fish to jump or swim along the ladder. Salmon are not the only species to use this unique bypass system. At 366 meters (roughly 1200 feet) it is considered to be the longest wooden fish ladder in the world.
An interpretation center with viewing screens (via underwater cameras) allow visitors to see fish moving along the ladder.
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