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
The Cascades Subdivision Landslide
The Cascades Subdivision landslide occurred in a 700-acre development which was being built by Maurice Wilder of Clearwater, Florida.
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 happenNorth Carolina Geological Survey’s Findings
again.
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. 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.
In their assessment report the NCGS referenced other Western North Carolina landslides caused by contractors' use of graphitic-sulfidic road fill.
When developers build roads in a subdivision or planned community North Carolina law stipulates that they declare their subdivision roads either private or public. Mr. Wilder's roads were recorded as private. If private, property owners are required to sign the following liability document at time of sale:
Sample Subdivision Street Disclosure Statement
Pursuant to N. C. G. S. Section 136-102.6 _______, as the Declarant of _______,
issues this statement indicating that all of the roads within_______ are private. It is the obligation of _______ Homeowners' Association, Inc. (hereafter "Association") to maintain and keep in good repairs all of the private roads in _______Subdivision. It is mandatory for all property owners in _______ to be a member of the Association and the property owners, with the exception of the Declarant, have an obligation to pay assessments to maintain the private roads. The Declarant specifically states that the streets have not been constructed in such a manner to allow inclusion on the State highway system for maintenance.
No Escape Clause
If the Wilder landslide had occurred after lots had been sold The Cascades property owners, without exception, would have been obliged to repair the damage.
The use of the Subdivision Street Disclosure Statement as a conveyance document for streets in a hazardous-land subdivision has not been legally challenged so property owners remain uninformed about the financial risks. The following material information is omitted on Western North Carolina Mountain Subdivision Street Disclosure Statements:
—Land in this subdivision is steep slope. Soils above a 15% grade are generally not “suitable” or “poorly suited” for residential development— “Some are too unstable to be used as a foundation for buildings or roads.” References: Western North Carolina Soil Surveys/North Carolina Geological Survey.
Horseshoe Cove Subdivision Landslides
The Horseshoe Cove Subdivision landslides provide an example of the financial consequences of sharing ownership of roads built on unstable soils. Below are some photographs of the damage caused to the subdivision's roads. Engineering evaluations commissioned by the property owners found that their subdivision had been built on a hazardous-land tract. The Horseshoe Cove Subdivision was designed and developed by Don Condren. Mr. Condren is currently doing business in Jackson County.
Post-development hazardous-land determination did not invalidate the terms of the Horseshoe Cove Subdivision Street Disclosure agreement. Collectively the Horseshoe Cove property owners paid $300,000 to repair roads and drainage. The preventive landslide techniques (Costs: $2,868,000-$5,230,000) recommended by McGill engineers were not pursued.
The Federal Emergency Management Agency
Members of various influential groups, such as the Association of Realtors and the Home Builders Association have suggested that landslides and other hazardous-land conditions are immaterial threats to property owners.
Federal officials disagree.
Although the Federal Emergency Management Agency cannot force states to provide hazardous-land real estate disclosure they are requiring all disaster-designated counties to evaluate and assess all real property for landslides, wildfires, and flooding as part of their hazard mitigation plans. These unpublicized real estate risk compilations are under the purview of county planning boards. Ask to see them.
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