Research indicates that in a few decades, Alsek River may further change its final course. The rapidly retreating Grand Plateau Glacier separates Alsek River and lake from nearby Grand Plateau Lake. Geologists predict that when the two lakes merge, Alsek River will abandon its current outlet in favour of the steeper way to the ocean through Grand Plateau Lake and a small embankment, moving its outlet some 17 miles (28 km) to the southeast, within the confines of Glacier Bay National Park.
