Hydrologists from the USDA Natural Resources Conservation Service report high snow pack in Alaska, to no surprise to Alaskans, but the extent of record breaking snows could be alarming.
Snow survey data, gathered from SNOTEL and snow course sites, is used to forecast river flow volume, breakup flooding potential, avalanche danger, summer forest fire probability, and fresh water availability for municipalities and power generation. And, don’t forget that salmon fishing is directly affected by high water – when the rivers run high, the tendency is for the fish to migrate in higher concentrations, meaning shorter, faster runs. Snow survey information also contributes to calculating winter severity with respect to wildlife survival.
Breakdown of record-breaking: The Kenai Peninsula has received abundant snow this winter with six snow courses having the 2nd highest record snow water content being recorded. Demonstration Forest, Pass Creek, Resurrection Pass and Moose Pass snow courses had higher water contents in 1980 while Jean Lake and Kenai Moose Pens had higher water contents in 1992.
The five snow courses in the Ninilchik Dome area are 143 percent of average with the Anchor River Divide SNOTEL site reporting 54 inches of snow depth with 16.0 inches of water content, 127 percent of average.
At the head of Kachemak Bay the Bradley Lake SNOTEL sites were measured with the Nuka Glacier snow course having 118 inches of snow depth and 52.3 inches of water content, 132 percent of average. The Kachemak Creek site measured 70 inches of snow depth with 38.3 inches of water content.
The April-July volume flow forecast for Kenai River is 122 percent of average
Within the Arctic Valley, the Anchorage Hillside SNOTEL site showed 185 percent snow water content compared to average. The Moraine SNOTEL site, above Eklutna Lake, broke a 1960 record with 176 percent of average snow water content. Most impressive is in Portage Valley, where snow water content was 252 percent of average. We can expect high water in the creeks and should be cognizant of flooding and stream bank erosion.
Prince William Sound region broke three records at these sites: Worthington Glacier, Lowe River, and Mt. Eyak. The highest percent of average was found at Mt. Eyak, but records only started there in 2005 in comparison to Lowe River where record keeping began in 1972. Lowe River broke a 1980 record of 66 inches of snow with a whopping 74 inches this year. Anglers will need to be attentive to how the high water affects the fish run.
The Upper Yukon snowpack is eerily similar to 2009 when the village of Eagle flooded. Flooding can still be avoided if spring temperatures rise slowly, but there is plenty of snow to melt with two snow courses recording the second highest water content on record: Meadow Creek recorded 15.4 inches of water content as compared to the record in 2008 of 16.3 inches. Mt. McIntyre, near Whitehorse, recorded 8.9 inches of water content compared to 9.5 in 2011.
The Log Cabin snow course set a new record snow water content this year with records going back to 1958. All of the snow courses in the Upper Yukon and Dawson/Stewart/Pelly regions measured above average water content, varying from 120 to 138 percent of normal. Let’s hope breakup is slow and steady.
For more information about snowpack, precipitation, runoff and water supplies for specific basins, visit http://www.ambcs.org/.
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