River
Alsek River
250 km from source to mouth · Canada and United States.
Canada and United StatesFlows into Gulf of Alaska
In numbers
Length
250km
Average flow
840m³/s
Basin
28,500km²
Drop
559m
from 559 m to 0 m
Countries
2
The journey
From source to mouth
250 km of river and 4 stops on the way: 0 towns and cities on its banks, dams, bridges and the tributaries that feed it.
- 0 kmDezadeash Riverat 559 m
- 5 kmDezadeash Rivertributary
- 5 kmKaskawulsh Rivertributary
- 165 kmTatshenshini Rivertributary
- 224 kmAlsek Lake50 km²
- 250 kmGulf of Alaskaat 0 m
Water level along the river (RiverATLAS; the height is exaggerated). Towns: GeoNames and Wikidata; bridges, dams and tributaries: Wikidata.
River in Yukon Territory, British Columbia, and Alaska
At the mouth it carries 839 m³/s on average: an Olympic pool every 3.0 seconds. It drops from 559 m to 0 m, 2.2 m per kilometre on average. Its basin covers 28,500 km², about the size of SB. Highest water, with the snowmelt: May; lowest: from January to April. No large dam holds it back: it is one of the world's free-flowing rivers.
Where to start
- Yakutat Airport (YAK)Nearest airport with scheduled flights, 72 km from the cityCar hire at JNU airport (Juneau)Discover Cars · Affiliate link↗
- JulyThe best months to visit
Alsek River, month by month
Highest water: May
Lowest water: from January to April. Freezing months (average below −4 °C): from November to March. Melting snow makes up much of its water. Best months to visit: July.
From about 110 m³/s in the lowest month to 2,700 m³/s in the highest. An estimate: the monthly flow is modelled from the lowest and highest months of WaterGAP (RiverATLAS, 1971–2000) and the rain and snow along the river (WorldClim). Dams change the real rhythm. The chip is the average air temperature; below it, the month's rain.
Plan the trip
Plan the trip: boat trips, a bed by the river, a car
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The basin
Alsek River: the basin in numbers
28,068 km² of land send their water to this river. This is what lives on it.
- 765people live in the basin
- 1,191maverage altitude of the basin
- 729mmof rain a year (basin average)
- -3.4°Caverage air temperature
- 63%protected areas
- 2.1%covered by lakes
- 12%glaciers
- 39%permafrost
What covers the basin
- 7% Forest
- 12% Ice
RiverATLAS (HydroATLAS v1.0, CC BY 4.0): land cover, people, protected areas, glaciers and dams over the whole basin upstream of the mouth.
Cross-checked with our atlases
Alsek River in our other atlases
What our sister atlases know about the waterfalls on this river, the lakes it flows through, the beaches at its mouth, the mountains where it rises and the islands off its mouth.
1lake on its wayLakeyas
2mountains at the sourcePeakyas
Lakes and reservoirs (1)
Lakes it flows through, by Lakeyas
- Alsek Lakekm 24450km²
Lakeyas is coming soonOpen Lakeyas ↗
Mountains at the source (2)
Within 15 km of the source, by Peakyas
- Mount Martha Black10 km away · prominence 1,797 m2,512m
- Profile Mountain6.8 km away
From space
The source and the mouth, seen from orbit
Sentinel-2 cloudless 2016 by EOX IT Services GmbH (contains modified Copernicus Sentinel data 2016), CC BY 4.0. The glowing line is the river as drawn by RiverATLAS.
Photos
Alsek River in pictures
Tributaries
Where it flows, and what flows into it
Tributaries (3)
Also: Tatshenshini River, Dezadeash River, Kaskawulsh River
Where these numbers come from
| Name, length, places | Wikidata (Q1781851) · CC0 |
|---|---|
| Course, profile, basin | RiverATLAS v1.0 (HydroATLAS, Linke et al. 2019) · CC BY 4.0 — followed from the source to the mouth given by Wikidata |
| Flow | WaterGAP (RiverATLAS), 1971–2000 · CC BY 4.0 |
| Climate along the river | WorldClim (RiverATLAS), 1970–2000 · CC BY 4.0 |
| Towns, bridges, dams | Wikidata · CC0; GeoNames · CC BY 4.0 |
| Along the river | © OpenStreetMap contributors · ODbL |
| Images | EOX Sentinel-2 cloudless 2016 · CC BY 4.0; Wikimedia Commons |
| Our other atlases | Lakeyas, Peakyas — Wikidata · CC0; © OpenStreetMap contributors · ODbL; GeoNames · CC BY 4.0; HydroLAKES · CC BY 4.0; NOAA OISST |
Every source and licence is on the data sources page.
The family
Do you prefer beaches, lakes, mountains, waterfalls, islands, rivers or canyons?
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