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USGS Geologist Doubts Cause Of Oso Landslide Will Ever Be Pinned Down

File photo of Oso landslide
Washington Governor's Office
File photo of Oso landslide

A federal geologist doubts the cause of the deadly landslide near Oso, Washington, will ever be fully pinned down.

File photo of Oso landslide
Credit Washington Governor's Office
/
Washington Governor's Office
File photo of Oso landslide

During testimony in Olympia Monday, U.S. Geological Survey scientist Jonathan Godt said heavy rains in February and March certainly contributed to the slide. Geologists have also ruled out an earthquake as a trigger. But Godt says a big missing piece is groundwater flows, for which there's no data.

"We didn't have instruments in the ground at the time the landslide occurred and you can't put the slide back up on the slope," Godt said. "So from an observational standpoint, that opportunity is lost."

Godt spoke to the Washington Forest Practices Board, a panel which is reexamining logging rules around landslide prone areas. A Washington state geologist and a private consulting geologist also presented there Monday. None would speculate if historic clear-cuts had anything to do with the March landslide.

Investigators are asking for more money from FEMA to probe why the Oso landslide traveled so far from its origin.

The death toll from the March 22 slide in Snohomish County stands at 41. Two additional people are still listed as missing.

Copyright 2021 Northwest News Network. To see more, visit Northwest News Network.

Tom Banse covers business, environment, public policy, human interest and national news across the Northwest. He reports from well known and out–of–the–way places in the region where important, amusing, touching, or outrageous events are unfolding. Tom's stories can be heard during "Morning Edition," "Weekday," and "All Things Considered" on NPR stations in Washington, Oregon, and Idaho.

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