Spur Lake to the Brady Glacier


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North America » United States » Alaska » Glacier Bay
September 14th 2007
Published: November 18th 2007
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“Spur Lake” is a 'glacially dammed lake' - one end of the lake is a wall of ice, the Brady Glacier. Ice calves off the wall and floats in the lake. Spur Lake is officially not named - you won’t find the name on any maps. I call it ‘Spur Lake’ because it looks, from a map, a bit like a thorn or, spur. But if you come to visit you can call it anything you’d like!

Glacially dammed lakes are unusual in that one side of the lake is a wall of ice that holds back the water. Most of the glacially dammed lakes here appear to have no outlet or the obvious outlet is dry most of the year. Most water escapes the lake under the ice. These lakes fluctuate a lot in lake level - exactly what happens is not really well know (it is all happening under the ice), but the theory goes something like this: in the winter the under-ice outlet channel gets restricted by the moving ice, as summer comes on there is more and more water (slightly warmer water) flowing through the glacier and the under-ice channel becomes larger. Often what happens that
leaving the inflatable leaving the inflatable leaving the inflatable

we always put the inflatables up in a tree or root wad so the bears will be less likely to find and chew on them...
a catastrophic break through occurs, either under the ice or at the surface, and the lake partially drains in a period of a few days. The Icelanders have a name for this type of catastrophic draining of a glacial lake: jökulhlaup.

The Brady Icefield is melting - the trees/shrub layer starts a couple hundred feet above the current level of the ice. When the ice was higher, Spur Lake jökulhlaups were probably infrequent, the lake drained out the low end of the valley on the east end of the lake. Until about 2000 all the aerial photos showed Spur Lake as full. Sometime around 2002 we noticed that the lake had drained. When these lakes drain the resulting lakebed does not look at all natural, it looks like a ‘reservoir’ (what the Brit’s call a ‘dam’). Usually when you see a ‘bathtub ring’ appearance to a ‘lake’ it means it is not a natural lake but a man-made water body. Lakes that have jökulhlauped are natural lakes.

Spur Lake has hundreds of trees trunks rising from the lake bed. These trees where most likely alive and living many hundreds of years ago. As the ice level went up
in to the woodsin to the woodsin to the woods

no trails just go
the lake was formed and the trees remained under the lake until being exposed in 2002.

I’d wanted to hike to Spur Lake as soon as I started seeing the lake level down - the newly exposed lake bed created a realistic hiking route from the ocean onto the Brady Ice sheet.

The weather drives me. Weekends of clouds keep me low, kayaking the coast, why climb a mountain to be in the clouds? My friend Nate says you just got to go… you never really know what the weather will be like the next day. And it’s true. But this weekend was starting blue sky and the forecast was good. So pauhana work on Friday early and off we went!



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18th November 2007

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Thanks, Bill. I love the info and the photos. Post more of your trips! Jim.

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