Wednesday, November 11, 2009

I-40 Pigeon River Gorge Rockslides: Past, Present and Forecast

As reported by Vicki Hyatt, editor of The Mountaineer, the Pigeon River Gorge section of I-40 has and will continue to be a rockslide-hazardous corridor. The following is a reprint of her November 3, 2009 article “I-40: A troubled history.”

Rock slides that halt travel between Haywood and Newport, Tenn., have plagued Interstate 40 since it first opened in October 1968. Just four months after the dedication of the route, known early on as the Pigeon River Road, occurred in February 1969, when a slide blocked traffic on all four lanes of the route.

The area near the access road to Waterville Dam was grouted, rock was drilled, dynamited and then filled with liquid cement to halt the earth movement. It was the first of many actions that would be taken through the years to stabilize an area engineers had long warned would pose problems in the future.

In 1974, the pavement again started showing signs of movement, according to an article in The Mountaineer, and it wasn’t unusual for smaller slides to cause periodic delays.

The interstate was closed for two weeks in March 1977 after about 40,000 tons of rock slid onto I-40 about two miles inside the Tennessee state line. At the time, a state geologist noted the area was the site of a major fault with mostly coarse rock which could easily fracture and slide. News reports said geologists were striving to determine if there was one big slide or two separate ones in the area.

In May 1978, a major slide that led to a wreck in which seven people were inured closed the eastbound lanes of I-40 near the Fines Creek exit. The $1 million repair job included work on the cut to prevent future slides and halt slippage of a rock bank near the exit. Two-way traffic was maintained in the westbound lanes during the work, and three people were killed in a head-on collision when slide repairs were underway.

A February 1981 rock slide, about half a mile east of the Tennessee line, covered both the east and westbound lanes of I-40 with boulders, dirt and trees.

The frequent slides made it apparent a longer-term solution was called for, and the state transportation department announced plans to reconstruct four miles of interstate through Haywood County near the Tennessee line to reduce the danger of rock slides. The first phase of the project would shift two lanes of traffic away from the mountainside and toward the Pigeon River, a May 20, 1981 article in The Mountaineer stated. The second phase would remove loose rocks from slopes and take other measures to install wire mesh to catch the rocks before they hit the highway.

Since the roadway opened, two people had been killed as a direct result of falling rocks and another three died in a collision at a landslide detour near the Fines Creek exit, the article noted. At the time, the state’s assistant transportation director said experts believed the possibility of rock slides was of such a magnitude that it could close the road.

In the fall of 1981, a N.C. Department of Transportation report projected $10.3 million — three times the $1.5 million per mile cost to build the roadway — would be needed to reduce the danger of rock slides on I-40 near the Tennessee line. This amount would be enough to correct problems at five potential slide areas, a news article reported. Even with the stabilization work, state officials noted there was no way to stabilize cut slopes entirely.

Before a contract was finalized for the work, a March 1982 slide buried the westbound lanes near the Tennessee line. The project continued into 1984. It included shifting three miles away from the rock slopes and toward the Pigeon River, as well as bolting rocks too large to remove in the five problem areas identified as most susceptible to slides. The project included a chain-link fence to prevent smaller boulders from falling onto the driving lanes.

In March 1985, a massive slide blocked both tunnel entrances. The repair cost about $6 million and nearly a year to clean up.

In July 1997, a massive slide again closed the roadway, taking six months and $2.5 million to clean up.

Road a political victory

Haywood County leaders won a hard-fought battle more than 60 years ago when the county became the last in the state to have a 1921 road law implemented. The law promised a paved roadway linking every county seat and linking every county adjoining another state to that state’s county seat. The long-identified route between Haywood and Newport, Tenn. was a water-level route following the Pigeon River. The route received state funding and was begun five years before it was necessary to designate an interstate route between Knoxville, Asheville and Spartanburg, S.C. The interstate designation, which held the promise of vastly increased commerce — and economic prosperity — was coveted by both Haywood leaders and those in Madison and Buncombe counties, which pushed for a four-lane highway along the French Broad River.

Haywood leaders were able to garner support from the Tennessee Highway Commission, as well as counties to the west. That support, along with free right-of-way along the Pigeon route and a head start on construction, won the prize.

See more pictures of rock slides throughout I-40’s history at www.themountaineer.com.

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