Losers by a Landslide
Could Oregon have prevented landslide danger?
BY CAMILLA MORTENSEN
Late in the afternoon of Dec. 11, a sea of mud, logs and rocks slid into Hwy. 30 near Clatskanie, carrying a mobile home into the road and burying other homes under a deadly mass of muck.
|A landslide near Clatskanie Washes a mobile home onto Hwy. 30|
It was a miracle no one was killed. Or was it? It seems that when it comes to landslides, Oregon logging and building interests prefer to hide their heads in the sand.
Initial media reports praised the Oregon Department of Forestry for evacuating the homes and closing the highway just hours before the slide hit. But later it was revealed that the state has known for 10 years or longer that the area was at particular risk for landslides. In fact, a 1933 landslide killed four people only a mile and half from the Dec. 11 slide, according to a January Oregonian article.
Even more surprising was the revelation that the logging that may have led to the December slide was done on land owned by OSU’s College of Forestry, Oregon’s premier research facility on forests and logging.
In a response to reports on OSU’s involvement, the school stated, “There is no evidence thus far to suggest that OSU’s timber harvesting or research operations on this land contributed to the landslide.” The College of Forestry generates funds through its own logging (timber harvests) and gets 10 percent of its funding through a tax on logging.
The OSU statement goes on to say that one of the first areas to move in the slide was a ridgeline that had been logged and replanted 15 years ago. Though OSU says, “the link between clearcut logging and landslides is complex,” others think the links between logging and landslides are fairly clear.
Over the past several months, Oregon landslides have not just destroyed homes. A slide near Tillamook cut Internet service for half of Australia, and the recent slide near Oakridge shut down Amtrak and freight service between Seattle and Los Angeles. Studies are still underway to determine the exact causes of the slides, but both slides occurred in areas affected by logging.
Doug Heiken of Oregon Wild drew up a document on the connections between cutting trees and sliding hillsides shortly after a 1996 slide in Douglas County killed five people. His analysis of a number of landslide studies showed that many elements of logging, from roadbuilding to herbicide spraying, contribute to the likelihood of landslides in areas that have been clearcut.
Loggers often spray herbicides to prevent newly planted seedlings from being choked out by other plants, but according to Heiken, the spraying “initiates the decay and loss of strength in the roots of plants that survived the logging.”
In forested land “roots of trees provide cohesion in the soil,” says Heiken. After an area is clearcut, roots decay and then disappear. The process takes between nine and 12 years, depending on how big the cut trees were and how the land was “reforested,” he says. “But little seedlings do not replace big healthy trees.”
Heiken’s document is starting to draw attention again, thanks to Oregon’s recent spate of slides. He says that after the 1996 deaths, “the laws didn’t change dramatically.”
In 1997 Senate Bill 1211 created a task force to look into landslides and public safety and to address “rapidly moving landslides in steep, forested areas.” In 1999 Senate Bill 12 directed state and local governments to protect people from landslides that are “difficult for people to outrun or escape.” It also directed the Department of Geology and Mineral Industries to create maps of “areas potentially prone to debris flows.” This would help prevent people from building houses and logging in areas of extreme landslide danger.
So why are homes still getting wiped out by slides?
The winter storms have made this season more landslide-prone, experts say. Heiken says, “We can’t prevent huge storms from happening, but we can prevent clearcuts and roads from happening.”
The maps showing the areas of landslide danger were created, but according to the Oregonian article, they were “shelved” to keep them from interfering with land development. The statutes regulating logging in landslide-prone areas had loopholes like allowing logging above “lesser used” roads and near “recreation” homes. The statutes also allow for logging in “high landslide hazard locations” if the state forester decides “that any landslides that might occur will not be directly related to forest practices.”
The maps, created by Jon Hofmeister, cover western Oregon and are available at the www.coastatlas.com website. Homes in the Coast Range are among those at risk for landslides.