The immediate threat to the Situk River - renowned for its steelhead fishing - and the Yakutat economy from an advancing Hubbard Glacier appears to have passed.
But government officials are still looking at ways to prevent flooding that could occur in the future if the glacier chokes off Russell Fiord.
Last month, the U.S. Forest Service said Hubbard Glacier was surging forward by as many as 12 feet a day. As of April 22, it was about 640 feet off of Gilbert Point at the northwest edge of Russell Fiord.
Forest Service spokesman Ray Massey said Thursday the glacier has backed off and is now more than 800 feet from Gilbert Point.
The agency is cautiously optimistic that trend will continue through the summer but will keep monitoring the glacier, said Bob Gubernick, an engineering geologist for the Tongass National Forest.
The glacier has periods of advance and retreat during the year, often surging forward in spring and backing off in the autumn. But the overall trend over time is forward, Gubernick said.
That's why several agencies are looking at long-term ways to deal with the flooding threat.
Yakutat residents fear if the glacier seals off Russell Fiord, creating a lake, the lake eventually would spill over into the Situk River drainage and flood valuable fishing habitat, hurting Yakutat's economy.
The Situk River has one of the largest wild steelhead stocks in the world and the largest documented steelhead population in Alaska, with an annual run of about 6,000 to 9,000 fish returning each year.
The river also is a salmon spawning ground, contributing to subsistence and commercial fisheries.
There is geological evidence that a sealed-off Russell Fiord has flooded the drainage in the past, Gubernick said.
"You can see all the old river channels," he said.
It's highly likely that will happen again if the current trend continues, although the event could be one year or 50 years away, Gubernick said.
The advancing glacier sealed off the fiord once in the 1980s and again in 2002. In those years, the rising lake water eventually eroded the moraine at Gilbert Point and drained out there.
The Forest Service has scheduled a meeting in late May to discuss the issue with Yakutat residents, Massey said.
The agency is working with the Army Corps of Engineers, Gov. Frank Murkowski's office, other agencies and Yakutat residents on possible ways to avoid Situk flooding in the future, Massey said.
Possibilities include a channel to divert water south to the Yakutat Foreland and possibly all the way to the Gulf of Alaska. Another possibility is a tunnel at Gilbert Point.
Massey estimated those plans would cost at least $50 million to $100 million and take five to six years to plan and construct.
It's not clear who would pay for the project, he said.
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