Geologic hazards Landslides related to Hurricane Ivan

Updated September 2004

The remnants of Hurricane Ivan tracked across western North Carolina on September 16-17, 2004. In addition to flooding, property damage and interruption of transportation corridors occurred owing to landslides and downslope movement of earth and rock triggered by very heavy and intense rainfall.

Return to our "What's News" page for a link to a page showing counties affected by landslides from Hurricane Frances.

Landslide fact sheet — Western North Carolina

Click here for a landslide fact sheet for western North Carolina (PDF file only).

Counties affected by landslides — Western North Carolina

The following graphic shows North Carolina counties affected by landslides for which we have information as of 11:00am, Tuesday, September 21, 2004. We plan to update this map as additional information becomes available.

 

North Carolina Geological Survey provides assistance

Peeks Creek Debris Flow Update - Sept. 21, 2004

Heavy rains from Hurricane Ivan triggered the Peeks Creek debris flow, sometime around 10:00 p.m. on Sept. 16, 2004. Investigations are underway to determine the underlying geologic causes of the debris flow that originated near the top of Fishhawk Mountain at about elevation 4400 feet. The path, or track, of the debris flow is about 2 miles long from top to bottom end near the confluence of Peeks Creek and the Cullasaja River.

The focus of the initial investigation is to determine if rescue and recovery operations along Peeks Creek would be in danger from additional landslides along the debris flow track. Although there are some unstable slopes along deeply incised segments of the track, it is unlikely that if landslides occur in these areas they would impact current recovery operations, unless the slides occur during heavy rainfall. Piled up trees, soil and rocks in narrow areas of the debris flow track, however, have created a potential for debris dams to form. These areas could unsafely impound water during heavy rainfall, thus presenting a dam failure flooding potential in the steep valley.

The geologic investigation into the causes of the debris flow will take some time, but all evidence so far points to the debris flow originating on steep slopes (35-55 degrees) with relatively thin soil (less than 3-5 feet thick). The Peeks Creek debris flow appears to have occurred naturally, and does not appear to be related to any human activity such as road building in the area where the debris flow began.

No evidence found to date confirms the presence of a preexisting body of water in the upper part of the debris flow track that would have contributed a large volume of water to the Sept. 16 debris flow. The North Carolina Geological Survey is trying to locate aerial photography of the area taken between Sept. 5 and Sept. 16 to determine if any slope movements or water impoundment had occurred during Hurricane Frances that may have contributed to the Sept. 16 event. It is possible that heavy rains from Frances may have initiated some movement in area, and the following rainfall from Ivan provided enough water to trigger the rapid, catastrophic debris flow of September 16.

Debris flows and other landslides have occurred in the past, and will occur in the future in the North Carolina mountains. Hurricanes triggered widespread debris flows in the North Carolina mountains in 1916 and again in 1940. A strong tropical depression in 1977 also triggered numerous debris flows. Although many debris flows occurred in remote areas, debris flows and other types of landslides caused fatalities in both 1916 and 1940.

For additional information

The contact for additional information about geologic hazards in North Carolina is Mr. Richard Wooten, P.G.; his e-mail is Rick.Wooten@ncmail.net. He is located in the Swannanoa, North Carolina office (western North Carolina) and can be reached by telephone at 828.296.4500. His mailing address is: 2090 U. S. Highway 70, Swannanoa, North Carolina 28778. An alternate North Carolina Survey staff geologist contact is Dr. Jeff Reid, P.G., 512 North Salisbury Street, Raleigh, North Carolina, 27699-1612. His telephone number is 919.733.2423 x403. His e-mail is Jeff.Reid@ncmail.net.

Macon Co. — Peeks Creek Community — A debris flow, a type of landslide, destroyed fifteen homes and resulted in several deaths.

This view was taken from a helicopter by a North Carolina Geological Survey staff geologist on Sunday, September 19, 2004.

Macon Co. — Peeks Creek Community — This view was taken from a helicopter by a North Carolina staff geologist on Sunday, September 19, 2004. Much of the nearly 2-mile-long debris flow track is shown.

 

Image taken by North Carolina Geological Survey staff geologist on September 19, 2004.

Macon Co. — Peeks Creek Community — This view was taken from a helicopter by a North Carolina staff geologist on Sunday, September 19, 2004. This view shows the steep slope near the point where the debris flow originated.

 

Image taken by North Carolina Geological Survey staff geologist on September 19, 2004.

Macon Co. — Peeks Creek Community — This view is looking upslope along the debris flow track and shows some of the debris flow deposits.

Image taken by a North Carolina Geological Survey staff geologist on September 19, 2004.

Macon Co. — Peeks Creek Community — This view shows some of the debris flow deposits. Note people for scale.

Image taken by a North Carolina Geological Survey staff geologist on September 19, 2004.

Macon Co. — Peeks Creek Community — This view shows a destroyed home located in the lower third of the debris flow track.

 

Image taken by a North Carolina Geological Survey staff geologist on September 28, 2004.

Macon Co. — Peeks Creek Community — This view shows a damaged home located in the lower third of the debris flow track.

 

 

 

Image taken by a North Carolina Geological Survey staff geologist on September 28, 2004.

Macon Co. — Peeks Creek Community — This view shows a destroyed vehicle located in the lower third of the debris flow track.

 

 

 

Image taken by a North Carolina Geological Survey staff geologist on September 28, 2004.

Macon Co. — Peeks Creek Community — This view shows two destroyed vehicles and wooded debris located in the lower third of the debris flow track.

 

Image taken by a North Carolina Geological Survey staff geologist on September 28, 2004.

Macon Co. — Peeks Creek Community — This view shows a home that was moved off its foundation by the debris flow (home on left); a completely destroyed home (debris pile) is on the right. These homes were located in the lower third of the debris flow track.

Image taken by a North Carolina Geological Survey staff geologist on September 28, 2004.

Macon Co. — Peeks Creek Community — This view shows two structures damaged by the debris flow. These homes were located in the lower third of the debris flow track.

Image taken by a North Carolina Geological Survey staff geologist on September 28, 2004.

Macon Co. — Peeks Creek Community — This view shows one structure damaged by the debris flow. This structure is located in the lower third of the debris flow track.

Image taken by a North Carolina Geological Survey staff geologist on September 28, 2004.

Macon Co. — Peeks Creek Community — This view shows the size of the boulders transported by the debris flow (downstream to the left). These deposits are is located in the middle third of the debris flow track.

Image taken by a North Carolina Geological Survey staff geologist on September 28, 2004.

Macon Co. — Peeks Creek Community — This view shows boulders oriented in the direction that the debris flow moved (downstream to the left). These deposits are is located in the middle third of the debris flow track.

Image taken by a North Carolina Geological Survey staff geologist on September 20, 2004.

Macon Co. — Peeks Creek Community — This view shows the debris flow track (remnants of Fish Hawk Mountain road in background). Debris flow moved moved downstream to the right. These deposits are is located in the middle third of the debris flow track.

Image taken by a North Carolina Geological Survey staff geologist on September 20, 2004.

Macon Co. — Peeks Creek Community — This view shows the scoured debris flow track and earlier colluvium behind geologist. Debris flow moved downstream to the left. These deposits are located in the middle third of the debris flow track.

Image taken by a North Carolina Geological Survey staff geologist on September 20, 2004.

Macon Co. — Peeks Creek Community — This view shows a destroyed cabin in the upper third of the debris flow track. Debris flow moved downstream to the left.

 

Image taken by a North Carolina Geological Survey staff geologist on September 20, 2004.

Macon Co. — Peeks Creek Community — This view shows the source area for the debris flow. The exposed bedrock area is about the size of a football field and slopes 35 to 55 degrees. Geologist (right upper corner for scale).

Image taken by a North Carolina Geological Survey staff geologist on September 20, 2004.

Macon Co. — Peeks Creek Community — This view shows scrape marks on the exposed bed rock in the debris flow source area. These indicate material riding over the bedrock. Yellow pocket knife (center) for scale.

Image taken by a North Carolina Geological Survey staff geologist on September 20, 2004.

Haywood County — Rock slide along 1-40. Courtesy of WRAL-TV on-line edition of September 18, 2004.

Haywood County, NC — Hebo Mountain — Tension cracks opening up in garden adjacent to house. Slope failure behind house.

 

Image taken by North Carolina Geological Survey staff geologist on September 24, 2004.

Haywood County, NC — Hebo Mountain — Tension cracks opening up in garden adjacent to house.

 

Image taken by North Carolina Geological Survey staff geologist on September 24, 2004.

Haywood County, NC — Hebo Mountain — Tension cracks opening up in garden adjacent to house foundation (depression adjacent to house foundation). There is a slide scarp in the left part of the image (see image above).

Image taken by North Carolina Geological Survey staff geologist on September 24, 2004.

Haywood County, NC — Hebo Mountain — Embankment failure (debris flow) along driveway leading to home. The material from this embankment failure impacted state road NC209.

 

Image taken by North Carolina Geological Survey staff geologist on September 24, 2004.

Buncombe County, NC — Starnes Cove — Home destroyed by a debris flow. Image taken by a North Carolina Geological Survey staff geologist on September 23, 2004.

Buncombe County, NC — Starnes Cove — Home destroyed by a debris flow. Courtesy of Asheville Citizen-Times on-line edition of September 18, 2004.

 

 

Buncombe County, NC — Starnes Cove — Home damaged by a debris flow. Image taken by a North Carolina Geological Survey staff geologist on September 23, 2004.

Buncombe County, NC — Starnes Cove — Debris flow track; note muddy overbank deposits and mud line on tree about 20 feet above geologist's head. Image taken by a North Carolina Geological Survey staff geologist on September 23, 2004.

Image taken were two debris flow tracks coalesced.

Buncombe County, NC — Starnes Cove — View looking uphill along the scoured track toward a debris flow source. Image taken by a North Carolina Geological Survey staff geologist on September 23, 2004.

Buncombe County, NC — Starnes Cove — View looking uphill toward a debris flow's apparent source at an abandoned road. Image taken by a North Carolina Geological Survey staff geologist on September 23, 2004.

Red dashed line shows the failure surface on the ground slope. Flattened vegetation shows the direction of movement downhill toward geologist.

Buncombe County, NC — Starnes Cove — Tension crack in road bed about debris flow scarp. This feature indicates likely future instability.

 

Image taken by a North Carolina Geological Survey staff geologist on September 23, 2004.

For additional information

The contact for additional information about geologic hazards in North Carolina is Mr. Richard Wooten, P.G.; His e-mail is Rick.Wooten@ncmail.net. He is located in the Swannanoa, North Carolina office (western North Carolina) and can be reached by telephone at 828.296.4500. His mailing address is: 2090 U. S. Highway 70, Swannanoa, North Carolina 28778. An alternate North Carolina Survey staff geologist contact is Dr. Jeff Reid, P.G., 512 North Salisbury Street, Raleigh, North Carolina, 27699-1612. His telephone number is 919.733.2423 x403. His e-mail is Jeff.Reid@ncmail.net.