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Difficulty III+(V+)
Length Miles
Flow Range 20000 - 40000 CFS
Flow Rate as of: 7 years ago 8400 [CFS] ℹ️
Reach Info Last Updated 11/30/2010 7:00 am

River Description

Season: Summer. If you plan to run Turnback Canyon you can try to hit low flows at the end of May or in September. Early runs face the risk of an iced-in Alsek Lake and late season runs face the hardship of deteriorating weather conditions.


The Alsek, made famous as a whitewater run after Walt Blackadar's solo first descent in 1971, joins the ranks of the Grand Canyon of the Stikine and Devil's Canyon of the Susitna as one of North America's legendary class V+ bigwater runs. Only a handful of people have ever run all three.

This run is however accessible to those who don't want to tackle the four miles of intense class V+ whitewater in Turnback Canyon, as the rest of the run only has a few class IV sections and is mostly a long wilderness float that is routinely run. Most of this run is located within the boundaries of Canada, but because it ends with a paddle out on the lower Alsek, with a take-out on Dry Bay in Alaska, the run is typically included in guides to both Alaskan and Yukon whitewater. If you aren't interested in tackling Turnback Canyon and the idea of a long portage doesn't sound too appealing, you can always check out the Tatshenshini which offers a similar wilderness experience and joins the Alsek downstream of Turnback Canyon.

British Columbia's Tatshenshini-Alsek Park is bordered by the adjacent national parks of Kluane in the Yukon and Glacier Bay and Wrangell-St Elias in Alaska, creating a 97,000-square-kilometer ecological unit and bi-national World Heritage Site. Situated in the extremely rugged northwest corner of British Columbia, in 1993 it became the fourth component in the largest international protected area in the world. Half the landscape is permanently covered in snow and ice--the other half fosters forests and tundra and stable populations of wildlife untouched but for a historic aboriginal presence. To ensure the preservation of the entire ecosystem, the Tatshenshini and Alsek, are completely protected from headwater to source, creating the only large river drainage in North America that is completely safeguarded.


The run starts on the Dezadeash River at Haines Junction in the Yukon. From here you have a 17-mile float down to the Kaskawulsh River, and at this confluence the Alsek River begins. Don't be surprised to encounter weak current and strong headwinds. As you continue on down past the confluence, the river remains braided before it finally settles into a single channel within the next 10 miles. The upper section of the river flows through relatively open terrain in comparison to the Tatshenshini which is the next drainage to the south. This is largely due to the history of floods occuring through glacial dam breaks; these floods have scoured the landscape in recent times.

The first whitewater of the trip begins above Lowell Lake where class II/III rapids are encountered. You can expect the lake to be filled with icebergs; early in the season, the lake may be iced in. The river is bigger and faster as it exits Lowell Lake. Two of the bigger rapids, aside from those in Turnback Canyon, are found between the lake and the Bates River confluence. The first is Sam's Rapid, located six miles below the lake; Bill's Rapid, a headwall drop, is another two miles downstream.

You will pass the Bates River 64 miles into the trip and within 10 miles you'll cross the border into British Columbia. Soon Tweedsmuir Glacier will come into view and 94 miles into the trip you will arrive at Turnback Canyon. You can expect to spend two days portaging the canyon or alternatively arrange for a helicopter shuttle that will take about 15 minutes (for all practical purposes this is the only real option for raft trips). There are two options for the portage route. You can work your way along the glacial moraine for a shorter but more challenging hike, or you can head up and over the moraine to the longer portage on Tweedsmuir Glacier. If you're thinking about running Turnback Canyon, expect to spend a day scouting. Embick's guide has detailed descriptions of the rapids. The canyon ends after only six miles.

Below the canyon there is one more class IV rapid and then it's a float down to the Tatshenshini confluence which is reached 126 miles into the trip. At this point the river has expanded to a wide channel.

As you continue downstream you'll reach Alsek Lake, where the Alsek and Grand Plateau Glaciers flow into the lake, calving off massive chunks of ice and creating a wonderland of icebergs. If you're lucky enough to have a clear day, Mt. Fairweather rises above the landscape to the southeast.
The icebergs create unique hazards as they can flip without warning and can also form river-wide dams or sieves, particularly in the main channel at the entrance to Alsek Lake. As you enter the lake, marked by Gateway Knob which rises up on river right, be sure to spend some time scouting out your options. Wind can blow the ice up against different parts of the lake, effectively blocking different routes. Conditions may change quickly as you might find your preferred route effectively blocked one day and then find the area clear of ice the next day as prevailing winds push it to another part of the lake.

After you leave the lake there is a short section of rapids before you start to see cabins. A side channel to the left takes you to the air strip at the fish processing plant. If you are unsure of the route, be sure to stop and spend some time to figure it out. If you miss the appropriate channel you will need to haul your boats back upriver.


The first order of business in planning your trip is to obtain an information packet and permit information for the river. The trip takes you through Yukon Territory (Kluane National Park), British Columbia (Tatshenshini-Alsek Provincial Park), and Alaska (Glacier Bay National Park); river use is regulated and coordinated by these park units.

The put-in is on the Dezadeash River at the bridge in Haines Junction which is in the Yukon, 150 miles north of Haines, AK. Haines can be reached by a convenient ferry out of Juneau which makes a good meeting place for those flying in. Another alternative is to fly or drive to Whitehorse in the Yukon, then drive 100 miles west to Haines Junction. A third alternative is to drive the 600 miles from Anchorage. If you've got someone driving gear up from the continental US, it's more than 1600 miles from Seattle on rugged roads which makes for a couple of long days; consider the Alaska Ferry.

Midway through the trip you may want a helicopter to facilitate the portage of Turnback Canyon. Inquire with the Parks for licensed pilots who can provide this service.

While you can drive to the put-in, logistics from the take-out get a bit more complicated as you need to arrange for a charter flight out. The Park Service can provide information on current charter services, but you'll probably want to fly from Dry Bay to Yakutat, where you can get commercial jet service. Make sure you have factored in the logistics of hauling your gear out. Most river runners use rafts so if you do take a hardshell make sure it will fit in the plane you've arranged. Keep in mind that poor weather conditions on the coast may mean that you won't be able to get a flight out the day you arrive; be prepared to wait through cold and wet conditions for suitable flying weather.

Lat / longitude coordinates of the put-in are approximate. Since much of this run is in Canada, it hasn't been easy to get online maps until recently. Some maps, also linked at the right edge of this page, include:
Atlas of Canada - Turnback Canyon. Note that this is a fully interactive map; you can zoom in and out and re-center to get topo maps throughout the Canadian portion of your trip.
Here's one source for hardcopy maps in the vicinity of Haines Junction.

Additional Information

Rapid Descriptions

Turnback Canyon--Beginning

Class - 5.2 Mile - 94
Rapid Thumbnail Missing

The infamous! You don't have to run it if you don't feel up to it.

Turnback Canyon--End

Class - N/A Mile - 104
Rapid Thumbnail Missing

Tatshenshini River Confluence

Class - N/A Mile - 140
Rapid Thumbnail Missing


Gage Descriptions

The gauge is located downstream of the confluence with the Tatshenshini River and near the take-out. There is an Alsek above Bates River gauge maintained by the Water Survey of Canada's waterweb. It's not a real-time station, but data are routinely uploaded and you can view past discharge data (be sure to select discharge as the parameter type; to convert to cfs multiply by 35.7). For all practical purposes then this gauge can simply tell you what the flow was once you return home; Embick notes that if you multiply the value on this gauge by 1.5 it will give you the approximate discharge for Turnback Canyon.

Directions Description

We have no additional detail on this route. Use the map below to calculate how to arrive to the main town from your zipcode.

Date Flow Result Factor  
2008-06-18 n/a Fatality High Water Read More




Paul Martzen


Thomas O'Keefe


Matt Muir


Revision #Revision DateAuthorComment
1199710 03/27/11 Paul Martzen permit update
1195301 11/30/10 Thomas O'Keefe permit update
1195296 06/03/09 Matt Muir Added "rapid"--Tat confluence
1198817 11/30/10 Thomas O'Keefe permit update
1189795 05/25/06 n/a n/a