Wednesday, March 5, 2008

Laurelmor and Landslides

Laurelmor is one of the largest mountain slope communities ever planned for Western North Carolina. Laurelmor, a Ginn Resort Property, is located in the Blue Ridge Mountains and land for the project encompasses 6000 + acres in Watauga and Wilkes counties. The majority of the resort is situated in Watauga County. Advertising and promotional material for the project detail a golf course, 50 miles of roads, plans for 1500 ridge top and mountain slope homes and 400 condos. The Laurelmor web-site opens with music and a panoramic mountain vista. The script says "The Mountains are Forever"...

Western North Carolina mountains are not forever. In fact these ancient formations have proven to be extremely unstable building locations. Watauga County was declared a federal landslide disaster area in September 2004 and the North Carolina Geological Survey has determined that the county is at severe risk of future landslides. The January 2008 landslide probability maps show that 20% of the county is rated as high hazard and 41% of the land lies in the track of previous debris flows.

Here is a look back at landslides in Watauga County by the North Carolina Geological Survey:

Life, Death and Landslides: The August Storm Event in Watauga County, North Carolina

In August 1940, the southeastern United States experienced two major flood events. The larger of these events, the remnants of an unnamed Atlantic hurricane, affected portions of northwestern North Carolina and eastern Tennessee between August 13th and 14th. Aerial photography interpretation and fieldwork completed by the North Carolina Geological Survey documents at least 600 debris flows and slides occurring in the southeastern portion of Watauga County during this storm. Newly acquired 1940 aerial photography indicates that approximately 100 to 200 more debris flows occurred in central and southern Watauga County. The greatest concentration of debris flows occurred along the Blue Ridge Escarpment; primarily the Elk Creek reentrant in southeastern Watauga County.
Landslides claimed twelve lives, nine of those in the Stony Fork Township near Deep Gap in eastern Watauga County. Rainfall amounts were high in the area, generally ranging from 12 to 13 inches for the week, with the highest intensity rainfall occurring on the evening of August 13th. Flooding and mass movements effectively cut off major portions of the county for over two weeks. Debris flows and flooding severed a 6-mile section of U.S. 421 in 21 places between Deep Gap and Maple Springs in Wilkes County. Washouts and landslides also dissected the nascent Blue Ridge Parkway. In neighboring Caldwell County, flooding destroyed 90% of the bridges and mass movements closed many of the roads leading into Watauga County. Rescue, recovery, and relief operations for victims of the debris flows and flooding in the region were stymied and rescuers resorted to crossing difficult terrain on foot and by horse.
At that time, Watauga County was sparsely populated and largely agricultural; the U.S. Census Bureau reports 18,114 people living in the county in 1940. By 2000, the population had more than doubled (42,695), with most of the growth occurring in the last 30 years. Many areas shown on the 1940 aerial photography inundated by mass movements have since been developed due to the rapid increase in urban (~13%) and rural populations (~30%) since the 1970's. Another storm of similar magnitude would likely cause significant damage to lives, property and transportation corridors without careful land use evaluation and planning.

Rick Wooten, senior geologist with the North Carolina Geological Survey, provided the following data to Watauga County Commissioners and concerned citizens in an October 27, 2007 meeting.

Based on aerial photographs, 84 percent of the slopes [ in Watauga County] that gave way were covered by pasture or crops instead of trees. More than 130 homes have since been built in the paths of 1940 landslides and Wooten said those places would likely end up being “high hazard areas” on the state geologic map.

Additionally, 15 of the landslides that occurred during hurricanes Ivan and Frances in 2004 were at locations that also gave way in 1940. Regionally, major landslides occur about every nine years, with damaging landslides an annual occurrence. Since 2004, the number of landslides and erosion deposits in the statewide slope movement database increased from 400 to 4,500. This information was excerpted from Scott Nicholson's article, "Forum ignites interest in county plan," The Watauga Democrat, October 31, 2007.

The Ginn Company is developing and selling real estate in a clearly identified high risk landslide region. Plans for Laurelmor were approved prior to the completion of the Watauga landslide probability maps. It is unknown whether soil analyses and site specific studies are being performed for construction sites within the resort. If Laurelmor were being developed in California and in other jurisdictions, permits would be granted only after these safety investigations had been completed.

Considering the personal and financial risks, Laurelmor buyers should receive the following Natural Hazard Disclosure Statement:

Please be advised that you are buying property in a high risk hazard area and this will affect your ability to obtain insurance. Watauga County, location of Laurelmor, is in a state designated landslide district. The slope stability information provided by the federally mandated landslide mapping program was not available at the time this residential project was approved. Laurelmor is being developed under regulations that do not require site specific stability investigation.

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