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Last week’s localized storm triggers airport-area slides
By Lynn Hotaling
An Aug. 22 localized downpour that dumped massive rain on the Little Savannah watershed apparently triggered two slides on slopes adjacent to the Jackson County Airport.
One slide, labeled a debris flow by geologist Rick Wooten of the N.C. Geological Survey, a part of the N.C. Department of Environment and Natural Resources, brought a river of mud down the mountainside and over the driveway shared by the homes of R.L. and Brian Ammons off Ben Cook Road.
N.C. Department of Transportation District Engineer Jonathan Woodard, left, and Jackson County Airport Authority Secretary-Treasurer Jim Rowell take an up-close look at a slide triggered by an isolated Aug. 22 storm that possibly dumped 5 inches of rain on the Little Savannah watershed in a single hour. The slide, termed a debris flow by N.C. Department of Environment and Natural Resources geologist Rick Wooten, left a swath of mud down the mountainside, damaging the driveway to the homes of R.L. Ammons and Brian Ammons, located off Ben Cook Road. – Herald photo by Nick Breedlove
The heavy rain also caused additional movement at an older slide, located on Dewayne Pruett’s property, which is accessed from Ben Cook Road’s second entrance.
Wooten inspected both slide areas Tuesday (Aug. 30). Though his results are preliminary, he said it looks as though the material that moved down the slope in both slides is a by-product of airport construction.
“Based on what we’ve seen so far, it appears the material that flowed was put there when the airport was built,” Wooten said.
Wooten based his theory that the material in the Ammons slide was deposited when the airport was built on evidence that decayed logs were present in the soil that moved.
With regard to the Pruett slide, Wooten said most of it came down the mountain in 1977, and that some of it apparently broke away again last week.
“Our working hypothesis is that the material that moved appears to be related to airport construction,” he said.
The geologist also said that after climbing to the top of the ridge, he didn’t see evidence that another slide would occur in the immediate future.
“It doesn’t look extremely likely,” he said, adding that the slides should be monitored and that the Pruetts and Ammonses should be “mindful that some additional material may come down.”
Wooten visited the two sites Tuesday morning during the last stages of rainfall associated with Hurrican Katrina. He said no additional material moved during this week’s (Aug. 29-30) storm-related downpours.
The Jackson County Airport Authority has engaged Sylva contractor Paul Lewis to clean out a neglected drainage ditch above the Ammons’ homes in an effort to channel the water away from the driveway. Lewis began work Friday and has finished except for smoothing their driveway, he said.
According to Wooten, Lewis’ work should serve to divert the water.
The geologist also said he needs to talk with Airport Authority members to see if they’ve set up a long-term monitoring plan for the slopes.
N.C. Department of Transportation District Engineer Jonathan Woodard inspected the Ammons slide Friday with Authority members Tom McClure and Jim Rowell. Woodard said he didn’t see any evidence of slope failure.
“A tremendous volume of water started eroding the bottom of the hollow,” Woodard said. “There was so much volume and velocity that the water picked the soil up and carried it along, and the farther it goes, the bigger it gets.”
When asked if what had occurred above the Ammons house could be compared to the slide that killed five last September in Macon County’s Peeks Creek community, Woodard said the two have elements in common.
“The event is not similar. But probably a wash like this in a hollow that dammed up the main creek caused (the one at Peeks Creek),” he said.
McClure said Friday that the beginning of the Ammons slide is not on airport property, but that the Authority asked Woodard to evaluate it because they wanted a professional opinion. The Authority paid for Lewis to repair the Ammons’ driveway “to be good neighbors,” he said.
When asked for his opinion of the Pruett slide on Tuesday, McClure said he couldn’t comment because he hadn’t seen it. DOT engineer Woodard was scheduled to look at it Wedesday, he said.
McClure said he wasn’t aware of the problem above Pruett’s house until Friday when Pruett called and said he had runoff without mentioning a slide. McClure said he stopped by Pruett’s house on Friday after he looked at the Ammons slide but that no one answered the door.
“There’s been no problems there for 25 years; that’s why we want to have an engineer look at it,” McClure said, adding that Lewis had recommended building a retention pond as a way to retain runoff and slowly drain it in several directions.
Lewis, who has also inspected both slides, termed what he’s seen “a lot of water.”
The work he did near the Ammons homes was actually re-doing what he did 20 years ago, he said, adding that both the county and the Ammons had neglected it.
“There were trees 6- to 8-inches in diameter in that ditch,” he said.
With regard to the Pruett slide, Lewis pretty much agreed with geolgist Wooten’s assessment.
“It’s an old slide, and it was left the way the airport builders left it. There’s never been anything done about it,” he said. “However the rocks fell, that’s where they are.”
Lewis also said he didn’t see any imminent danger.
“It’s just my opinion, but I don’t see anything happening anytime soon,” he said.
If there was another slide, Lewis said he didn’t see it coming down on the Pruetts’ home.
Lewis said that the airport’s construction is to blame for both slides.
“Building the airport caused the runoff problems,” he said. “I was raised in that area, and there never were these kind of problems before they built it.”
According to Lewis, no effort was made to clean the site before airport construction began.
“They just went up there with big bulldozers and started in,” he said. “There was no pipe, and no drainage.”
Given that the airport is there, atop Berry Ridge, Lewis says its problems need to be addressed.
“It rained so hard (Aug. 22). When that happens, there’s going to be a problem – the water has to go somewhere,” he said.
Going in from the Little Savannah side and constructing a holding pond to slow the runoff might solve the problem above the Pruetts, but it could cost “hundreds of thousands,” Lewis said.
Neither Pruett or R.L. Ammons is pleased with how airport officials are handling the situation.
“No, I’m not satisfied,” Ammons said. “They’ve hired Paul Lewis to work on our road, and Paul does good work. But all the water is coming from the runway. They’re going to have to put in a drainage system that will work on that airport.
Ammons knows about slides and the airport. He said the house he lives in was his father’s and had to be moved after the site it was on was condemned in the wake of a 1970s slide.
“(The slide) came off the other end of the rock fill, and there wasn’t a tree left,” he said. Mud came in on top of his brother Jimmy’s house, he said.
Pruett said he called Wooten on the advice of Jackson County erosion control officer Robbie Shelton.
Airport officials, he said, “say they want to help and be neighborly, but then they insinuate we don’t know what we’re talking about.”
Shelton said he has not seen the Pruett slide, but that he looked at the Ammons slide last Friday.
“It looks like it’s stabilized itself,” Shelton said. “It’s down to bedrock. It came right down that hollow and took a few trees with it, then spread out. It’s a muddy mess.”
The airport, which opened in 1976, lost 500 feet of runway to the 1977 slide. Jackson County had to buy out several land owners, including Jimmy Ammons, after their property was condemned.
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