08/22/19 14:08p The Five Ws of a Glacier Dam Release

The Five Ws of a Glacier Dam Release

What is a Glacier Dam Release?

Also known as a jökulhlaup (pronounced yokel-lop; literally "glacial run") describes a sudden water release from a glacier or glacier-dammed lake. They occur on glaciers around the world and vary immensely in side. They generally recur at intervals ranging from less than a year to several years.

Where is the Snow Glacier Dammed Lake located?

The Snow Glacier Dammed Lake is located in the headwaters of the Snow River east of Moose Pass, Alaska. The Snow River flows from the eight-mile long Snow Glacier high in the Kenai Mountains. About halfway up, the glacier dams a side valley that fills with rainwater and snowmelt forming a lake half a mile long and up to 450 feet deep.

 

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When is the Snow Glacier Dam expected to release?

The Snow Glacier Dam is releasing as of August 21, 2019. Water levels on the Snow River are steadily rising and are reflective of previous outburst events. Expect significant water level increases on Snow River and Kenai Lake through the weekend. Water may continue to rise on Snow River, Kenai Lake and the Kenai River through the weekend and early next week. Water will likely rise to the point of flooding the Primrose campground and other low lying areas by Friday afternoon, August 22, 2019. Water levels on the Kenai River below Skilak Lake will likely see a more moderate increase to bankfull conditions by early next week.

Who is expected to be impacted?

Cooper Landing, Kenai Lake, Primrose Campground and other low lying areas. The 2019 impacts are expected to create flooding on Primrose Road to Primrose Campground, 2-3’ of water over the road for several days, and water approached the foundations of houses along Primrose Road. In Cooper Landing, water was reported over some driveways. 

Please drive with caution. If you come upon a roadway that appears to be flooded, DON’T try to drive through it. If you come across barricades blocking off a flooded section of the road, DON'T try to drive around them. Turn around and find a detour. It’s closed for a reason.  Avoid flooded areas and avoid hydroplaning when you're driving on wet roads with standing water. Don’t destroy your car or risk your life due to impatience.

Why is this happening?

The Snow Glacier Dammed Lake releases its waters every two to four years, typically in the fall. The first recording of this is 1949, although evidence shows this happening since the early 1900s. During a glacial dam release, the release starts as a trickle and increases to a peak in five to fourteen days. The highest flow is just before the glacial lake has emptied. Afterwards, it will take two to four days for Snow River to return to its normal flow.