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Last Updated — August 2004
This page summarizes actual and estimated costs attributed to geologic
hazards in North Carolina. It provides the date(s) and level of events
also. The estimated damage and indirect costs have not been adjusted
for inflation. These include events related to:
High Hazard Dam Failure
| Date |
Level of Event |
Damages |
Indirect Costs |
| August 13, 1916 |
50+ year event |
Tropical storm triggers catastrophic failure of Lake
Toxaway Dam, Transylvania County. No known fatalities; several homes
destroyed. Resort closes; local economy depressed until the dam
was rebuilt in 1961. |
Resort closes; local economy depressed until the dam
was rebuilt in 1961. |
| 1976 |
10 year? |
Bearwallow Lake Dam failure caused four fatalities
within one family. |
Dam repair costs. |
| May 26, 2003 |
10 year |
Hope Mills Dam fails after 6-9" of rain. Dam,
roadway, and bridge replacement costs exceed $6 million. Rainfall
from this event also triggered the failure of two other dams in
the region. |
Emergency response; homeowner relief. |
Abandoned mine collapse and subsidence
| Date |
Level of Event |
Damages |
Indirect Costs |
| February 18, 2000 |
N/A |
Collapse of Phoenix Mine, Cabarrus Co. $100,000 home
condemned. |
Extensive legal fees; state and county agency investigation
(collapse and contaminant); costs exceed $100,000. |
| 2000 - present |
N/A |
Subdivision built over North State Mine, Guilford
County. Investigation and mitigation costs exceed $50,000. |
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Landslides (regional events)
| Date |
Level of Event |
Damages |
Indirect Costs |
| May 1901 |
100+ year event |
Widespread floods and debris flows in Buncombe, Henderson and
McDowell Counties. Railroad tracks covered by slides for hundreds
of feet. Rail lines, bridges and roads destroyed. Exact damages
unknown, but probably in excess of $0.5 million.
|
Rail, bridge and road transportation disrupted. |
| July 16, 1916 |
100+ year event |
Widespread floods and hundreds of debris flows in
Transylvania, Henderson and Buncombe Counties. Scores of fatalities
and destroyed structures. Rail, bridge and road transportation destroyed.
Exact damages unknown, but probably exceeds $100 million. |
Transportation disrupted. Crop and private property
damage. |
|
August 10-17,1940 and August 28-31, 1940
|
100+ year event |
Two hurricanes caused widespread flooding though the
southeastern U.S. Flooding and hundreds of debris flows caused 26
fatalities in N.C. mainly in the Pigeon River basin (Avery,
Watauga, Ashe, Buncombe, McDowell, Yancy and Wilkes Counties). Rail
lines, bridges and roads destroyed. Exact damage unknown, but probably
exceeded $20 million in N.C. alone. |
Private property and crop damage. Transportation disrupted. |
| November 6, 1977 |
10 year event |
Widespread flooding and scores of debris flows in
Buncombe and McDowell Counties. Roads and bridges destroyed. Exact
costs unknown but probably exceed $3 million. |
Private property damage. Emergency response. |
| February and March 1990 |
15 year event? |
Heavy rains during February and March triggered numerou
debris flows in western N.C. Total road repair costs exceed $6.7
million. |
Transportation disruption. Private property damage.
Damage to trout farms. |
| May 5-7, 2003 |
<10 year event |
Heavy rains (7-15") in western N.C. trigger scores
of slope movements in Swain and Haywood Counties. Estimated damages:
One debris flow goes into Bryson City Reservoir. Reservoir abandoned.
Six major debris flows originate on slopes underlain by acid-producing
rock. Costs exceed $2.5 million. |
Transportation disruption. Emergency response. Community
water system destroyed. |
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Landslides (specific events)
| Date |
Level of Event |
Damages |
Indirect Costs |
| December 13, 1990 |
<5 year event |
Swain County debris flow destroys chlorinator for
Bryson City water system and mobile home. Direct costs in excess
of $60,000. |
Municipal water system disabled for 2-3 days. Roads
blocked, utility lines destroyed. Emergency response. |
| October 3, 1995 |
<25 year event |
Sedimentation from debris flow triggered by Hurricane
Opel enters Franklin municipal watershed. Rehabilitation costs exceed
$5,000. |
Indirect costs unknown. |
| July, 1997 |
<5 year event |
Rock slide closed I-40 in Pigeon Gorge. Direct costs
exceed $10 million. |
I-40 blocked for over 20 days. Rerouted traffic, loss
of business and tourism. Costs probably exceeded $5 million. |
| June 1999 - June 2001 |
N/A |
Cut slope failure along I-540 in Wake Co. in Triassic
sedimentary rock near Jonesboro Fault. Direct costs of $3 million
include purchase of private property right-of-way. Movement aggravated
by Hurricanes Dennis and Floyd. |
Indirect costs include legal fees; investigation expenses
probably exceeded $50,000. |
| December 11, 2003 |
<2 year event |
Occupant killed and home destroyed by debris flow
in Maggie Valley, Haywood County. Home valued at $200,000. Road
construction and community water system repairs required. Legal
action pending. |
Emergency response and legal fees. |
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Sink holes (karst) subsidence
| Date |
Level of Event |
Damages |
Indirect Costs |
| August 3, 2001 |
N/A |
Sinkhole develops on I-40 and creates a safety hazard
at Interstate driving speeds. Repair costs exceed $50,000. |
Traffic disruption; investigation costs |
| 2001 |
N/A |
Dewatering of Boiling Springs Lake. Repair cost unknown,
but probably exceed $50,000. |
Property values decline. |
| 1965 - present |
N/A |
Investigation and repair of rail and road transportation
routes at Sunny Point Military Ocean terminal. Costs unknown but
probably exceed $500,000. |
Unknown |
| 1998 - present |
N/A |
Rocky Point Quarry - Investigations and mitigation
for mine dewatering. Concern for sinkhole development near I-40.
Exact costs unknown but probably exceed $100,000. |
Unknown regulatory agency and NC Department of Transportation
(NCDOT) costs. |
| 2003 - present |
N/A |
Onslow Quarry - Investigations and mitigation for
mine dewatering. Concern for sinkhole development along transportation
routes and private property. Costs unknown but probably exceed $20,000. |
Unknown regulatory agency and NCDOT costs. |
| 1995 - present |
N/A |
Groundwater contamination remediation at Camp LeJeune
military base complicated by influence of karst terrain on groundwater
flow. Initial investigations undertaken without prior knowledge
of karst features. Costs unknown, but probably exceed $1 million. |
Unknown state and federal regulatory agency costs. |
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Earthquakes
| Date |
Level of Event |
Damages |
Indirect Costs |
| 1811 - 1812 |
|
Damage in North Carolina from New Madrid (Magnitude
8.0) earthquakes. |
Cracked foundations and toppled chimneys. |
| 1886 |
|
Damage in North Carolina from Charleston (Magnitude
6.0) earthquake. |
Cracked foundations and toppled chimneys. |
| February 21, 1916 |
|
Skyland earthquake (I VII) in North Carolina |
Damage in Waynesville, Tyron, Skyland, and Forest
City, North Carolina. |
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Tropical cyclones / hurricanes (specific examples)
Damage estimates for these events are highly variable from one source
to another. Hurricane damage is not always confined to the barrier island,
so damage estimates for storms that inflicted damage to the mainland
include the mainland damage. The storms in this list with the greatest
mainland impacts relative to coastal impact were Fran and Floyd.
Further information about these storms are at:
Jarrell, J.D., Mayfield, Max, Rappaport, E.E., and Landsea, C.W., 2001,
The Deadliest, Costliest, and Most Intense United States Hurricanes
from 1900 to 2000, NOAA Technical Memorandum NWS TPC-1, web document
at http://www.aoml.noaa.gov/hrd/Landsea/deadly/index.html
National Climatic Data Center Storm Events Database, 19 July
2004, National Oceanic and Atmospheric Administration, 6 August 2004,
http://www.nc-climate.ncsu.edu/monitoring/events.html
| Date |
Level of Event |
Damages |
Indirect Costs |
| August 31, 1993 |
9 year |
Hurricane Emily (Category 3) did not make landfall,
and the center of the eye's closest approach as Lost Tourism about
20 nautical miles east of Hatteras Island. However, Emily caused
widespread coastal flooding with wind speeds up to 98 mph. These
strong winds produced the worst flooding on the Pamlico Sound sie
of Hatteras Island this century. NC coastal damage was estimated
at $50 million. |
Power outages, lost tourism, beach renourishment. |
| July 13, 1996 |
7 year |
Hurricane Bertha (Category 2) made landfall
midway between Wrightsville Beach and Topsail Beach. The primary
effects in NC were to the coastal counties and included storm surge
flooding and beach erosion, roof damage, piers washed away, fallen
trees, and crop damage. Heaviest damage was in Topsail Beach and
all of Onslow County up the coast to Emerald Isle in Carteret County,
which was declared a Federal Disaster Area. This hurrican had an
initial 8-10 foot storm surge, with maximum wind speeds of about
101 mph. Total NC damage estimate was about $310 million. |
Power outages, lost tourism, beach renourishment. |
| September 5, 1996 |
9 year |
Hurricane Fran (Category 3) made landfall at Cape Fear
with widespread power outages, wind damage to trees and roofs
as well as downed trees and power lines. Storm surges of 8-12
feet destroyed or seriously damaged numerous beachfront houses.
On Topsail Island, a 12-foot-high storm surge caused 40 feet of
beach erosion and wiped out dunes as overwash destroyed most of
the first row of beach houses and heavily damaged the rest. Extensive
flooding was responsible for additional damage as well as widespread
power outages.
Hurricane Fran was the worst natural economic disaster to occur
in North Carolina to date. The total damage estimate for NC was
about $3.2 billion. Damage to crops, livestock, and farm equipment
/ buildings was $400 million.
The greatest agricultural damage was in Sampson, Johnston and
Wayne Counties. Tens of thousands of homes were damaged by falling
trees. The copious rainfall produced many severe flash and river
floods. A full twelve days after the event, 150 secondary roads
were still closed. This hurricane was responsible for 24 deaths
statewide.
|
Power outages, lost tourism, beach renourishment. |
| August 26, 1998 |
9 year |
Hurricane Bonnie (Category 3) made landfall near Cape
Fear and caused widespread flooding and property loss with a 6-8
foot storm surge. This storm resulted in numerous reports of
downed trees, roof damage and widespread power outages. This hurricane
had wind speeds of up to 115 mph and resulted in one death in
NC.
Carteret County appeared to sustain the most damage from the
storm. Along the Outer Banks, soundside flooding form the Pamlico
Sound produced water levels 4-6 feet above normal in Manteo on
Roanoke Island and over portions of Hatteras Island where Route
12 was briefly closed due to high water.
Storm surge at the beaches of Onslow and Carteret counties was
generally 3-5 feet above normal with moderate beach erosion. North
Topsail Beach lost most of the protective dunes constructed after
the hurricanes of 1996. Total NC damage estimates exceeded $720
million. A Federal Disaster was declared.
|
Power outages, lost tourism, beach renourishment. |
| September 4, 1999 |
7 year |
Hurricane Dennis (Category 2) Meandered off the NC coast
for about one week, resulting in storm tides of 3-5 feet at the
coast and higher tides reported in the sounds. After being downgraded
to a tropical storm, Dennis made landfall on Core Banks just north
of Cape Lookout. Beach erosion and the storm tide effects were
extreme on the Outer Banks.
Unfortunately the hurricane approached eastern NC during one
of the highest astronomical tides of the month. The dune structure
on Hatteras Island was breeched in numerous locations. Just north
of Buxton, a 3,000-foot-long section of Highway 12 was completely
lost and a new inlet along the Core Banks was formed.
The town of Nags Head estimated their dune loss at $16.5 million.
Ocean storm surges were 3-4 feet above normal. Total NC damage
estimates of property and crops was about $67 million.
|
Power outages, lost tourism, beach renourishment. |
| September 16, 1999 |
7 year |
Hurricane Floyd (Category 2) made landfall near Topsail
Island with wind speeds of about 100mph. This hurricane was the
third costliest U.S. hurricane (1999-2000) and produced more human
misery and environmental impact in NC than any disaster in memory.
The 15-20 inches of rain that fell across the eastern half of
the state caused every river and stream to flood.
Ocean storm surge was 9-10 feet, inundating barrier islands and
causing extensive dune erosion. Floyd was responsible for coastal
damage, however, much of the real damage was by severe flooding
of more inland areas. This flooding was responsible for extensive
livestock deaths with more than 3,000 hogs, 90,000 turkeys, and
200 cows lost to drowninging. Animal waste and septic tanks added
pollution to the flooding.
Floyd was the deadliest hurricane since Hurricane Agnes in 1972,
and resulted in 35 deaths in NC. Total NC damage estimates were
about $4.5 billion. A Federal Disaster was declared.
|
Power outages, lost tourism, beach renourishment. |
| September 18, 2003 |
7 year |
Hurricane Isabel (Category 2) made landfall near Drum
Inlet with wind speeds of about 100 mph. Major ocean overwash
and beach erosion occurred along the North Carolina Outer Banks
where waves up to 20 feet in height accompanied by a 6-8 foot
storm surge.
In Dare County alone, several thousand homes and businesses,
several piers, and sections of Highway 12 were damaged or washed
away. A new inlet was opened near Hatteras Village. Widespread
wind and storm surge (6-10 feet) damage occurred in coastal NC.
Damage estimates for NC totaled about $500 million.
|
Power outages, lost tourism, beach renourishment,
isolation of Hatteras Village. |
Contact Information
For additional information about landslide hazards in North
Carolina, please contact Mr. Richard Wooten with our Asheville Regional Office:
2090 U. S. Highway 70,
Swannanoa, North Carolina 28778.
828-296-4632
Rick.Wooten@ncdenr.gov
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