Investigation of the recent Abyss Lake jökulhlaup - Informal preliminary report

Grover, Scott; Soiseth, Chad; Yerxa, Rusty

Abyss Lake is roughly 5 miles up the Brady Glacier from Dundas Bay at ± 900 feet elevation, approximately 27 miles west of Bartlett Cove. It is a relatively large, deep glacial lake lying in a tributary valley to the Brady and dammed on its SW end by the trunk valley glacier. It normally drains into the Dundas River headwaters from an outlet at its east end. Sometime around Sept 1, 1997 the lake suddenly emptied about 180 vertical feet of its water under the ice in a jökulhlaup (an Icelandic word for a glacial outburst flood) leaving a perfect "bathtub ring" that is plainly visible from the air. The lake is ±1 ¾ miles long and ± ½ mile wide, so that was a lot of water (estimated volume, 131 million m3). The water rushed downhill beneath the glacier and poured into the Oscar River's channel and down that drainage into Dundas Bay, sweeping trees, debris, sediments and presumably unlucky bears into the saltwater. First word of this came to the Park from charter captain Rusty Owen in Dundas Bay who noticed trees floating in the water, and from Art Hayes of Frontier Air who saw the lowered lake level while on a flightseeing tour.