The Aniakchak River, a Federally-designated Wild and Scenic River, is located within the Aniakchak National Mounment and Preserve providing an
opportunity for a remote river expedition on the Alaska Peninusla. Trips usually take place during
the month of July. Plan for 3-4 days but be prepared for longer as weather conditions often dictate
The Aniakchak Volcano underwent a catostrophic explosive erruption approximately 3400
ago that formed the current caldera. Smaller erruptions have occurred more recently, with the last
one in 1931. Surprise Lake, located within the 5.9 mile diameter caldera, is the source of the
Aniakchak River. This caldera has its own microclimate marked by consistently wet weather and
harsh winds. Despite this it offers opportunities for exploration and hiking across the volcanic
From the lake the river begins at a slow pace for the first mile before entering the "Gates", a
1500 foot gash in
caldera wall. Here the river drops at a rate of 73 feet per mile with class IV whitewater. The river
remains class II/III for the next 10 miles (if you're in an inflatible be sure to pack the patch kit as
the sharp volcanic rocks can do a number on your boat). At the confluence of Hidden Creek the
river enters the steep 83 feet per mile section where volcanic bedrock on either side and boulders
in the channel constrict the flow. The pace of the river begins to slow considerably over the next
as you leave this section and continue the remainder of the journey on a low-gradient alluvial river
that takes you to the ocean.
The river system
supports all five species of salmon and Surprise Lake provides spawning habitat and a nursery for
sockeye salmon and artic char. Dolly Varden are also present. Wildlife are abundant and brown
bear are common along this river so be sure to take proper precautions and be prepared for
LOGISTICS: The expense of getting to this river and the unpredictable weather keep usage
low. You can get commerical service into King Salmon or to Port Heiden. From either of these
airstrips you'll need to arrange for a float plane charter to Surprise Lake. King Salmon
is further away (150 miles vs. 20 miles) but offers more options. You will also need to arrange for
pick up at the end of your trip where the river meets the ocean at Aniakchak Bay. Float planes can
land in the bay or wheel planes can land on the beachhead. Poor weather conditions can delay
flights so plan accordingly. There is a shelter at the beach for boaters awaiting pick up. This region
is extremely remote with no practical access to outside assistance.
Look for 1000-2000 cfs in July (based on
Permits are not required for this reach.
We have no additional detail on this route.
Use the map below to calculate how
to arrive to the main town from your zipcode.
Gates of the Aniakchak
Hiking in to the Aniakchak Caldera
Trail from Port Heiden
Logan on the Slide Drop
If someone gets hurt on a river, or you read about a whitewater-related injury, please report it to
American Whitewater. Don't worry about multiple submissions from other witnesses, as our safety
editors will turn multiple witness reports into a single unified accident report.
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