Kentucky Geological Survey Tracking Landslide Risks
LEXINGTON, Ky. - The word landslide can sometimes mean different things to different people. Politicians hope they'll be on the plus side of a landslide, but if you are a homeowner whose property butts up against a hill, a landslide can take on a very different and literal meaning. The Kentucky Geological Survey's Mike Lynch has the story.
James Christian of Boyd County was describing what happened as the back wall of his walkout basement blew out following heavy rains in the Spring of 2011. The backyard had slid away, removing the support under the basement wall, leaving much of the first floor hanging precariously with no basement wall supporting it.
Weeks before, he had noticed one floor of the house sloping downward….and the basement wall separating from the first floor.
The landslide that required Christian, his wife, and two daughters to abandon the house is not as uncommon in Kentucky as you might think. The sloping landscape of northern and eastern Kentucky are particularly prone to landslides.
Matt Crawford of the Kentucky Geological Survey is studying Kentucky landslides, and the Christian home is one of several Boyd County sites he visited this Spring. The heavy rains of LAST spring triggered the landslides.
The overriding causes of landslides include variable rock types, the type and thickness of the soil, and steepness of the slope.
And human development that disturbs those natural conditions--by modifying the slope-- creates the conditions for damages to above-ground structures, and buried infrastructure.
Boyd County Code Enforcement Officer Steve Sturgill took Crawford to several sites, pointing out the landslide-damaged houses which the County has condemned and which may be bought out by the county with state and federal help.
Because landslide damages are not covered by homeowner’s insurance, such “buy outs” may be the only solution for the owners. Crawford’s site visits provide communities with the geologic background needed to apply for the federal and state grants.
These landslide events don’t usually happen suddenly or without warning.
Crawford has been creating a database of landslides from the locations he has visited and from information provided by state agencies such as Transportation and Emergency Management. He now has 23-hundred landslide sites cataloged.
His work at the Geological Survey will help to better understand the geologic conditions that can produce landslides…and prevent developments from turning into disasters.