On Monday, the official death toll from the Washington State landslide rose to 33 identified victims, with three as yet unidentified and 13 still missing. Memorials and funerals for the dead began over the weekend as the recovery operations continued.
In the past week, revelations have come out about the use of decades-old maps in the issuing of logging permits above the towns of Oso and Darrington, and the 2004 rejection by Snohomish County of a plan to buyout the residents along the area, who would be buried by the fatal March 22 slide.
According to the Seattle Times, a 2004 plan to buyout the homeowners was rejected by Snohomish County officials as “prohibitive.” Estimated at $1.1 million for the 75 parcels of land involved, the proposal was made when the County Department of Public Works declared that a major slide could come down the Hazel Slope, crossing the river and inundating Steelhead Haven.
Officials based some of their analysis on a 2000 report by GeoEngineers, which said the Hazel Slope posed “significant risk to human lives and private property.” The report considered several scenarios, including rerouting the river anywhere from 900 to 2000 feet, with several buyout options for the potentially affected properties. Ultimately, the county opted to stabilize the base of the slide area instead.
A 2001 slide left a visible scar that would later become the head of the March 22, 2014 slide, and there had also been a significant slide just to the west, though when that happened is not clear. In January of 2006 another slide occurred which diverted the Stillaguamish River and flooded several houses in the area, also, as in the case of March 22, after heavy rains.
Nevertheless, the county issued permits for new homes in the slide area in 2006, four of which were built and all of which were destroyed in the March 22 slide. Eight people who lived in those houses, including four children, are now dead or missing.
According to the Times, residents and former residents of Steelhead Drive did not know about the severity of the risks and none were aware that the level was high enough for the county to have considered a buyout. Dale Dunshee, who sold his property in 2011, told the Times, “If I’d known it was that dangerous, I would have moved in a heartbeat.”
Davis Hargrave, a retired architect who lost a vacation home in the slide, said, “We are not a bunch of stupid people ignoring warnings. We all make risk assessments every day of our lives. But you cannot make a risk assessment on information you do not have.”
It has also been reported that the logging above the slide area was permitted based on decades-old maps and that an acre of unpermitted area was logged. Trees intercept and absorb water, stabilizing the ground. Certain areas are known as “recharge areas,” where there is risk of groundwater feeding into a slope and destabilizing it. Removal of trees from these areas contributes to erosion and can lead to or exacerbate slides.
Geologist Daniel J. Miller and hydrologist Joan Sias prepared a 1997 report commissioned by the Washington State Department of Ecology mapping the plateau of the unstable hill above Oso in which boundaries where groundwater could feed into the slope were drawn. In issuing logging restrictions later that year, the Department of Natural Resources cited the map used boundaries that had been drawn up in 1988.
Speaking to the Seattle Times, Miller stated, “We did the work. It was cited in the prescriptions as what you should do. And it appears from your comparison of the maps that it didn’t get done.” Miller’s statement that, “I suspect it just got lost in the shuffle somewhere” is difficult to believe, given the DNR’s praise of his study, including their statement in the 1997 restrictions that its methods should be followed.
Had the 1997 report’s recommendations been followed, approximately 12 additional acres to the west of the current boundaries would have been restricted from logging. The DNR approved Grandy Lake Forest’s request to cut 7.5 acres in 2004, most of which was in the Miller-Sias report’s recommended restricted zone. Their cutting was completed in 2005, and, according to the Seattle Times, extended about an acre beyond even the area for which it had a permit.
Despite protestations from forestry officials that it is “speculation” that logging played a role in the Oso slide, the destabilization of the soil in cut areas due to massive rainfall has been widely cited as a contributing factor in the deadly March 22 slide.
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[28 March 2014]