What’s in the Alsek River and Is It Safe to Swim In? 

Written by Fern Damron
Published: August 27, 2023
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The Alsek River is one of the most amazing waterways in the world. Beginning with its tributaries in Canada’s Yukon Territories, it flows southward for hundreds of miles through multiple protected parks and wildlife preserves. Its clean, clear, glacial waters take many twists and turns on their course to the ocean, feeding lakes and flowing through deep canyons along the way.

Thousands of people travel each year to see the scenic views and experience the true wilderness along the Alsek. But what lives in and around the river’s pristine water? Is it safe to swim in?

Contrast on the Alsek

The Alsek River runs hundreds of miles, from Canada’s Yukon to its outlet in southern Alaska.

©Daniel J. Quinn/iStock via Getty Images

Traversing the Alsek

If the weather is good, there are many parts where it is safe to swim in the Alsek. The river shoots off into braids, small ponds, and glacial lakes where its rapids slow down along its southward course. Along its path, the river passes through Lake Lowell and Lake Alsek, terminating at Dry Bay in Alaska.

People travel from all over the world to kayak, float, and fish in the Alsek, and many regard it as one of the premier river journeys on Earth. The northern tributaries are navigable by raft and kayak for many miles before they converge to form the Alsek proper. From there, it passes through a grizzly bear preserve, along Lowell Glacier, and through high-intensity rapids. It also passes through the largest ice field between the poles.

Not all parts are easily traversable, however. The Alsek’s cold water, swift rapids, and rocky bed quickly take a turn for the dangerous at Turnback Canyon. Though many have run the Alsek through the canyon since Walt Blackadar’s famous solo journey in 1971, the vast majority should reconsider. He and many others suggest that all but the most seasoned kayakers heed the canyon’s name and arrange portage to the other end by helicopter. Once there, the outlet of the canyon affords kayakers grand views of the Walker Glacier and a slower pace broken up by intermittent Class III and III+ rapids.

Though many elite kayakers have traversed the treacherous Turnback Canyon, most should arrange for helicopter transport to the southern outlet.

©AWWE83 / CC BY-SA 4.0 – License

Guided Trips

Because arranging a trip from afar can be quite difficult, river outfitters in the area offer group trips. These include route plans, plane charters, helicopter portage across Turnback Canyon, and the knowledge and experience of river guides. Oftentimes, guided trips down the Alsek include off-river hikes among the glaciers and mountains and walks along the banks.

The Alsek passes through some of the most remote wilderness on the content and opportunities for wildlife study and photography are innumerable. Visitors to the river and the parks it flows through may see moose, eagles, deer, and even wolves. In many places, like the Lava North Rapids (Class IV), bears are a common sight. They inhabit a wide range along the Alsek River, especially in the Yukon Territories which hosts the world’s greatest concentration of grizzly bears.

Even with a guide, it should be noted that the voyage along the Alsek is not for the inexperienced. Trips often last 12 days or more, passing through long stretches of remote wilderness. In many places, the river’s currents flow very quickly and wildlife encounters can prove to be dangerous.

Changing Course

The Alsek terminates at Dry Bay, where it feeds into the Pacific Ocean. Due to climate change and the resultant glacier melt, however, research suggests that it is well on track to changing course.

Before the river makes its final run toward the Pacific, it stops to fill Lake Alsek. On the lake’s southeastern side sits the melting Grand Plateau Glacier, which is the only thing preventing the lake from merging with the neighboring Grand Plateau Lake. Once the glacier melts away fully, the two lakes will join and the Alsek River will follow the steeper, eastern route to the Pacific. While researchers estimate that the river’s redirection will take place by 2061, it could feasibly happen within the decade.

Icebergs on Alsek Lake

With rising temperatures, more and more ice sloughs off the melting Grand Plateau Glacier and into Lake Alsek.

©mscornelius/iStock via Getty Images

With this change, the current route to Dry Bay would cease to exist, creating problems for the people and animals that rely on the river’s flow to sustain them. The salmon that take to the Alsek for spawning each year, already in decline, would need to relocate, forcing the fisheries that rely on them to close down or do the same. Likewise, the grizzlies and other predators that depend on the salmon as a major food source would need to adapt.

The rerouting of the river would also pose problems for the river outfitters, placing the river’s outlet solidly within National Park boundaries. There, federal regulations prohibit airstrips, roads, and landing pads, severely complicating most kayaker pickups.

The effects of climate change on the river and its residents will be quite drastic, changing the region forever. Those interested in experiencing the splendor of the Alsek River and witnessing the breathtaking, complex glacial ecosystem should do so before it is too late.

The photo featured at the top of this post is © Juan Carlos fotografia/iStock via Getty Images

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About the Author

Fern Damron is a writer at A-Z Animals who covers a variety of topics including plant life, gardening, and geology. They live off-grid in the Southeast U.S. and have been working to restore local Appalachian ginseng stands since 2020.

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