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Observers Guide to Glacier Dammed
Lakes in the Kenai River Basin
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Contact Information:
Agency: NOAA National Weather Service
Office: Alaska-Pacific River Forecast Center
Contact Telephone: 1-800-847-1739
Contact us by email:
Aerial Photography Task Description:
Glacier Dammed Lakes Release Timing: Glacier-dammed lakes often release in the fall months, but can release as early as June
Glacier Dammed Lakes Location: All three glacier-dammed lakes are in the vicinity of Seward, Alaska. The river basin affected by these
lakes is the heavily-used Kenai River basin. The release of a glacier-dammed lake (GDL) results in a significant rise in stage on the Kenai River with potential flooding.
A release of the Skilak GDL in January of 2007 caused significant damage in the communities of Soldotna and Kenai on the lower Kenai River.
Schedule: We would like photos taken on the following schedule (all dates approximate as they are weather dependent):
- July 15 - Skilak, Moose, and Snow GDL photos
- August 15 - Skilak, Moose, and Snow GDL photos
- September 15 - Skilak and Snow GDL photos
- October 1 - Skilak and Snow GDL photos
- October 15 - Skilak and Snow GDL photos
- November 1 - Skilak and Snow GDL photos
- More frequent flights (as frequent as 2-3 day intervals) are desired when a lake is about ready to release. The schedule depends on
what is found during each flight and all flights are weather dependent.
Detailed Guidance
Provided below is guidance on taking photographs of the glacier dammed lakes using text and low resolution images.
We would like image resolution of 1800 x 1200 pixels (2 MP) or better to allow us to zoom in on the water surface at the gage
to estimate the water surface elevation. All we are requesting from pilots are the photos... we will use our index
photos to evaluate the elevation. The primary photos desired at Skilak and Snow GDLs are the water surfaces at the
gage locations. Of secondary importance at these two lakes is an overall view of the lake. Moose GDL has no set of
markings and an overall view is all that is required.
Depending on image file size, sending 2 or 3 photos at full resolution per email should get through under our email
size restrictions. Please send the images to us at the link above since this will reach all of our staff to allow
analysis and use in the fastest time frame.
Skilak Glacier-Dammed Lake
Lat: 60 12 2 N
Long: 149 56 59 W
Approx Elev: 2900 ft
Guidance on the Skilak GDL photo documentation starts with the map that shows the "gage" location in the SW corner of the lake:
Skilak GDL Map
A photo taken from the north shows the lake features:
Example Photo
A photo taken from the south shows the gage location:
Example Photo
A photo taken from a helicopter show the "gage" rocks on the slope of the lake shore.
While this perspective
is ideal, flying this low in fixed wing may not be safe or practical:
Example Photo
A more common perspective from a fixed wing is illustrated in this photo, which has good coverage of the slope and water level:
Example Photo
Snow Glacier-Dammed Lake
Lat: 60 29 4 N
Long: 148 55 3 W
Approx Elev: 2700 ft
For Snow GDL, the map shows the gage along the north shore of the lake:
Snow GDL Map
As you approach the lake, this will be your view and the gage is on the east side of the ridge marked on this photo:
Example Photo
When you are on the east side of the pass, this photo will be your view and the gage location is marked:
Example Photo
In years when water levels are low, we would like a photo like this one that takes in the gage and the water level:
Example Photo
In years with higher water levels, water levels will be up to the gage and a zoomed shot will better show the water level on the gage:
Example Photo
Occasional shots when conditions are good of the overall lake such as this one (or even further back to show entire lake) are welcome:
Example Photo
or a different perspective at:
Example Photo
Moose Glacier-Dammed Lake
Lat: 60 28 50 N
Long: 149 1 27 W
Approx Elev: 2400 ft
For the Moose GDL, an overall view of the lake as you pass en route to or from the Snow glacier dammed lake is sufficient, since there
is no "gage" at this lake.
A good example of such a photo:
Example Photo
Thanks very much for your assistance.
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