Tuesday, October 28, 2008

No State Rule Book for Hazardous Land Development

Photo 1-View looking up the track of the August 31, 2006 embankment failure-debris flow from the development road near lot 107.

Photo 2-View looking downslope at the debris deposit and damage to lot 107
Photo 3-View of cracks in embankment extending northeast from the head scarp of the August 31, 2006 embankment failure-debris flow
Photos compliments of the North Carolina Geological Survey

A little over two years ago a road-building crew caused a massive landslide on Eagles Nest Ridge in Haywood County. Luckily, no homes were in the path of what has been called a “A Whopper of a Slide.”

The August 31, 2006 landslide occurred in a 700-acre development, called Cascades, which was being built by Maurice Wilder of Clearwater, Florida. The subdivision plat shows that the 90 foot wide by 1300 foot long debris flow would have severely damaged or destroyed any structures that would have been built on Lot 107 in the development.

After the landslide Dennis Franklin, contractor for the project, notified county officials and instituted temporary measures to stabilize the area. Marc Pruett, Haywood County’s erosion control supervisor, said that without notification he probably would not have known about the slide since no homes or residents were in danger.

Maggie Valley engineer Kevin Alford, who investigated the slide for a Cascades property owner, said that the failed section of the road bed occurred because
The upper road was built out of shot material (from) where they had to blast the roadway in there. It got too heavy. The sliding material acted like a bulldozer, scouring the slope of almost all soil and vegetation. It wiped out a path down to bedrock. It was like an elliptical -shaped bulldozer. It is an amazing thing when you see that kind of material go down the mountain. When you get up in the mountains and start building roads, there are good ways to build roads and bad ways to build roads. In a situation like that I think it would have been reasonable to do subterranean work to find out what was there. When you have a large amount of uncompacted rock fill that gets a lot of water in it, you have potential for slope failures. There is still more material up there, so it could happen again.
North Carolina Geological Survey’s Findings

Geologists investigating the landslide site found that the collapsed slope embankment was composed of highly unstable woody debris and graphitic-sulfidic bedrock fragments. Rain on this weak, improperly-constructed, roadbed probably precipitated the landslide.

During the course of their survey the geologists determined that the still standing ~ 300 foot long road embankment showed evidence of additional failures. They warned that if the fragile embankment is not properly stabilized, this land mass will pose a future threat to public safety. Recommendations to the developer included a professional investigation of the failed site in conjunction with extensive and expensive stabilization measures or removal of the remaining roadbed.

In their assessment report the NCGS reference other Western North Carolina landslides caused by contractors' use of graphitic-sulfidic road fill.

No State Rule Book for Hazardous Land Development

It is unknown whether Mr. Wilder followed the safety recommendations outlined by the North Carolina Geological Survey. Mr. Wilder, along with all other developers conducting business in the state, are left to their own best judgment on landslide remediation.

Interested parties should be aware of these pertinent facts:

1. Landslides and weak soils endanger most mountain construction sites in Western North Carolina.

2. Developers do not have to report landslides to the state or to their clients.

3. There are no independent safety experts on-site to monitor construction practices.

4. North Carolina does not provide any measure of regulation over hazardous land development even though the region was devastated by landslides in September 2004.

5. North Carolina does not require real estate land risk disclosure.

Wouldn't You Want to Know the Risks of Buying Real Estate in Haywood County?

Landslide hazard maps for Haywood County are scheduled to be released this year, yet commissioners have chosen not to share this relevant information.

Officials only acknowledge that there are "difficulties" such as steep slopes and water quality issues associated with mountain development. The fact is most of the county's developable land is extremely hazardous. Evidence proves that building sites are impaired by unstable soils, the threat of landslides and dangerous unsupervised construction practices.

Haywood County Commissioners and their Planning Board know that hazardous land development is a threat to public safety and homeowners' financial security. There is no reason for this information to be hidden from public view.

For a comprehensive look at landslide-triggered losses in Haywood County please read the following reports.

Gambling with the Unknown
Haywood County Landslide
Rain Triggers Mudslides in Two Western North Carolina Counties
Study brings bad news
Hunters Crossing Landslide...It's Still Moving
Building Homes Where Nature Didn't Intend Them to be Built.
Deadly Landslide in Maggie Valley
Western North Carolina Mudslides Damage Private Mountain Roads. Who is Responsible?
Mudslides and Landslides Affect Property Values in Western North Carolina

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