In 1998 the North Carolina Department of Emergency Management classified the following counties at high risk for the dangers of landslides: Alleghany, Ashe, Avery, Buncombe, Burke, Caldwell, Cherokee, Clay, Graham, Haywood, Henderson, Jackson, McDowell, Macon, Madison, Mitchell, Surry, Swain, Transylvania, Watauga, and Yancey. It should be noted that this assessment by the North Carolina Department of Emergency Management was made without landslide mapping.
In September 2004 fifteen of these western counties were declared federal landslide disaster areas.
Today only two counties have been mapped for landslide probability. Geologic investigators have determined that most of the mountain slopes in Macon and Watauga Counties are at high to moderate risk for landslides.
The residents of Western North Carolina and the residents of western Oregon face the ever present threat of landslides. As demonstrated by the following article landslide risk maps provide a clear and accurate picture of where not to build or buy. That is, if you know where to find them.
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"State keeps landslide danger zones hidden"
By Michael Milstein of The Oregonian January 19, 2008
State geologists predicted the landslide that crushed homes and severed U.S. 30 west of Clatskanie, but the state shelved the information in part because of concerns it would interfere with land development.
The prediction was spelled out in landslide hazard maps that state geologists drew up for all of western Oregon after landslides killed five people in 1996. The maps labeled most of the area involved in last month's U.S. 30 slide as posing "very high" or "extreme" landslide hazard -- the highest possible categories of risk.
They showed the danger extending from Oregon State University clear-cuts where the destructive chain of events began, downhill to an old earthen railroad crossing that allowed mud and debris to collect for more than a week, forming a lake. The debris broke loose Dec. 11, releasing a muddy torrent into homes that sat in the danger zone.
But people living in those homes never knew the maps existed -- even though the state spent $250,000 developing them to help protect life and property.
State foresters who reviewed logging more than a mile above the homes knew about the maps but did not refer to them, they said.
Other homeowners in a state full of risky terrain -- Portland's West Hills, the Coast Range, parts of southwest Oregon and elsewhere -- don't know whether they face the same risk as those west of Clatskanie.
That's because a little-known state board quietly withdrew the maps from official use in 2003 after city and county officials complained that they labeled too much area as hazardous and might restrict development and hurt property values, according to state documents and interviews with people involved. The state law that called for the maps included mandates that made local officials see it all as a regulatory headache.
The state never supplied money to refine the maps -- which cover 19 western Oregon counties -- the way cities and counties wanted.
The result is that the maps showing areas at highest risk of landslides remain unknown to those in the most danger.
"I bought it a year and a half ago," Mike Roubal said of his family's home west of Clatskanie, buried almost to its eaves by the Dec. 11 landslide. He evacuated shortly before the mud hit but lost several uninsured vehicles, including a classic 1955 Chevy, and is now struggling with paperwork to seek state and federal assistance. "I wouldn't have bought it if I would have known there was this kind of risk."
State officials estimate cleanup and repair costs for Highway 30 at $1.3 million.
A few cities and counties refer to the landslide maps when permitting new development, but many do not. That leaves some Oregonians to build new homes where they may sit in the bull's-eye of a coming landslide, experts say.
"The information is out there -- it's just not being used," said Scott Burns, a professor at Portland State University and authority on landslides. "It's a pity, because if we get more of these big storms, we're going to have more debris flows and more people in danger."
The lack of action reflects widespread reluctance by local governments to control development or take other action to reduce risk from hazards such as landslides, floods and tsunamis, said Gail Achterman, chairwoman of the Oregon Transportation Commission, who also headed a task force on landslide risk.
"The hard policy decisions have simply not been made," she said. "It's easier to do nothing and wait for FEMA to bail you out."
The landslide maps were among the most advanced of their kind at the time they were produced, Burns and other geologists said. When scientists checked the maps against evidence of historic landslides, they found that the maps correctly identified more than 90 percent of the areas buried in slide debris.
Geologists who worked on the maps said they're especially frustrated that what could have been a tool to protect people from disaster has been all but forgotten. The area west of Clatskanie, around Woodson, was one of the areas geologists specifically checked to verify the accuracy of the maps, said John Hofmeister, who led the mapping for the state Department of Geology and Mineral Industries.
A 1933 landslide killed four people about a half mile from where the slide struck last month. Heavy rains in 1996 produced small flows of rocks and debris in the area, residents said, but nothing like the major barrage -- compounded by the lake of debris that collected -- that struck last month.
"I figured it would happen there again, and it did," Hofmeister said. The mapping was so complex he tied together the department's computers on weekends -- for a month -- to sift through terrain data for clues about where slides might strike and how they would rush downhill.
"It really pulls at my gut" that the information isn't widely available, said Hofmeister, who left the department after finishing the maps and now runs a startup energy company. "It's not a good allocation of resources to have things like this get developed and get dropped for political reasons."
The maps emerged from statewide concern about landslide danger after the fatal slides of 1996. Slides that winter didn't kill anyone in Portland but damaged about 100 homes -- with statewide costs totaling nearly $100 million.
Gov. John Kitzhaber in early 1997 issued an action plan to reduce the likelihood of slides, and the risk to life and property when slides happen.
Some of his direction dealt with controlling logging of steep slopes, which can add to landslide risk. He also told the Oregon Department of Forestry and Oregon State University to map landslide hazards, giving local governments and property owners a picture of the risk.
A task force followed, and in 1999 the Legislature passed a bill outlining a state strategy on landslides. It gave the Department of Forestry authority to limit logging that could increase the risk of slides, but gave the mapping job to the state Department of Geology.
The job originally was to be done by four people over a couple of years, Hofmeister said. Instead, it turned out to be "me, myself and I" working on it, he said, with unpaid help from other landslide experts he consulted around the world.
The maps were meant to show cities and counties where they should more carefully review new development to make sure it wasn't in danger from landslides.
Former state geologist John Beaulieu, who headed the Department of Geology at the time, called Hofmeister's maps "a brilliant piece of work." He said "the technical part that he had to do was bigger and tougher and more cutting-edge than anyone realized."
The maps outlined areas with landslide risk, and then rated land inside those areas -- through colors -- from "extreme" to "low" hazard.
But the Legislature attached a mandate to the maps: Cities and counties had to adopt regulations requiring extra scrutiny of development in landslide zones. So the Department of Geology presented it to local officials in 2002 only as the broad outline of the hazard zones -- without the colored ratings, Hofmeister said.
That made it look like vast amounts of land faced landslide hazards, without providing local officials a way to distinguish areas of low hazard from those of extreme hazard -- such as Woodson.
"It's like taking away the painting and only leaving the frame," Hofmeister said. "All you're going to see is this big balloon."
Cities and counties complained that the maps were too general and included too much area. They quickly came to view the maps as a regulatory burden that could anger landowners and hurt property values. That was compounded by growing concern -- later embodied in the Measure 37 property rights debate -- that governments might have to compensate landowners if regulations took away use of their land.
"Do we really want to throw fuel on the takings compensation fire?" state Rep. Susan Morgan, R-Roseburg, wrote in a letter to Beaulieu at the time. She said landslide rules "will be placing a substantial financial burden on Oregon's citizens at a time when we are trying to encourage economic development."
"There was a very, very strong bias then that, 'I don't want to regulate development,'" Hofmeister recalls.
Shortly afterward, the commission that oversees the Department of Geology formally withdrew the maps from use. The department had a plan to refine the maps, but there was never any money for it.
The maps are now available only on an obscure state Web site - www.coastalatlas.net - that Hofmeister and another state employee worked on at night and on weekends. "Even geotechnical engineers don't know it's there," he said.
The state now hopes cities and counties will help pay for a new generation of maps based on laser measurements that provide a detailed picture of the land surface. That will probably take five years, at the earliest, said Vicki McConnell, the state geologist.
"Having that (earlier) map out there could in some cases be quite useful," she said. "However, we now have an opportunity to get even better information out there."
In landslide-prone Douglas County, Planning Director Keith Cubic said the county has tried to highlight the danger of slides for residents, but that only goes so far.
"We have heightened awareness, but we don't have the tool we were supposed to have," he said. "It's a frustration, because I think we could be doing a better job if we had the maps."
Columbia County, where Woodson is, might be one of the few counties that refers to the maps when considering new development. But Glen Higgins, the planning director, said there has been no drive to alert people whose homes may already be in danger.
"The general population kind of knows there's a risk out there," he said. "Whether the individual homeowner knows, I don't know."
CITIES, COUNTIES WORK TO LOWER LANDSLIDE RISK
While most experts agree that Oregon has fallen short of its goals to reduce landslide danger, a few cities and counties are out in front of the rest of the state.
After slides damaged homes around Salem in 1996, the city and Marion County used some of the federal disaster assistance money to hire state geologists to map landslide hazard zones. The geologists found that areas that might seem stable could end up sliding, damaging roads and houses.
There was also concern the city and county could be sued if they permitted building that compounded landslide danger.
The city and county then adopted ordinances that aimed to shift development toward terrain with lower risk, said Les Sasaki, a planner with Marion County who worked for the city of Salem at the time. The more extensive the development, the more careful the study the city and county required.
"We didn't want to say, 'No, you can't do anything,' but we did want to create caution around these hazards," he said. There was broad support for the actions. "Everybody sort of realized that the responsibility and the risk is shared," he said.
Now the city and county are known as leaders, said Scott Burns, a landslide expert at Portland State University.
"They're a national, if not international, model," said Andre LeDuc, director of the Oregon Natural Hazards Workgroup at the University of Oregon. He said other areas have lagged for various reasons, including a lack of funds and reliable information about landslide risk, plus reluctance to regulate land use.
"A lot of it is political will and money," he said.
Oregon City and Washington County now support more detailed landslide mapping by the state Department of Geology and Mineral Industries. Oregon City learned the hard way, after allowing construction of an apartment building on a known landslide site where sliding later caused serious damage.
State Geologist Vicki McConnell said she hopes to work with other local governments to map more of the state.
Sen. Ted Ferrioli, R-John Day, who worked on state landslide hazard bills, said state and local governments have a role in mapping and alerting residents to landslide danger, "so people can't say, 'I had no idea the risk was there.'"
But he also said it's difficult to shift money from schools and other needs to look for possible hazards.
"To take resources away from agreed-upon priorities to spend money on something that might happen is a hard sell."
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