The Pennsylvania Turnpike has revived plans to replace
the Allegheny Tunnels in Somerset County, a project that has been talked about
for nearly two decades.
The turnpike commission is considering six options for
abandoning the 6,070-foot-long tunnels, longest on the turnpike mainline. Three
would involve building new tunnels and three would carve an open highway
through the mountain either to the north or south of the existing tunnels.
Preliminary cost estimates for the “cut” options range
from $242 million to $345 million, while estimates for the tunnel options range
from $537 million to $694 million, according to turnpike consultant L.R.
Kimball. Annual maintenance costs for a tunnel would exceed $3 million, several
times what an open highway segment would cost.
Turnpike spokesman Carl DeFebo said the cost differential
was just one of several factors the commission will consider in choosing a
preferred option, possibly in the spring.
After that, design, acquiring property and securing
permits would take four years and construction at least two years, so “in the
best case you might be talking about six or seven years” before traffic could
be shifted to the new segment, turnpike project manager Jeffrey C. Davis said.
The turnpike commission began studying replacement of the
tunnels in 1996 but shelved plans to cut a 220-foot-deep notch in the mountain
amid opposition from environmental groups.
The Mountain Field and Stream Club, which owns 1,400
acres above the existing tunnel, again has come out against any plan to carve a
highway into the mountain, saying that would be disastrous to the landscape,
wildlife, plants and the water supply.
George Jugovic, general counsel for PennFuture, which is
representing the club, said it has filed public information requests and hired
its own expert to review the turnpike’s alternatives.
The group does not accept the turnpike’s cost estimates
as accurate, but even if a tunnel is more expensive, it would be worth the cost
for “a more environmentally sound, more environmentally sane” outcome, Mr.
Jugovic said.
He noted that construction of the final segment of
Interstate 99 near State College, which also involved carving into a mountain,
cost twice as much as originally anticipated after the excavation unearthed
highly toxic pyrite rock.
The first Allegheny Tunnel, which currently carries
westbound traffic, was built in the late 1930s and the second opened in 1965.
The tunnels are about 13 miles east of the Somerset interchange and 23 miles
west of Bedford.
In 1981, the turnpike commission completed a third lane
on the westbound approach to the tunnel to serve as a truck climbing lane to
ease congestion, and in 1996 changed the merge pattern so trucks could remain
in the right lane entering the tunnel. Some of the S-curves to the east of the
tunnels were straightened in a reconstruction project that was completed in
2008.
The tunnels underwent major rehabilitation in 1987 and
1988 and an inspection in 1995 and 1996 found rapid deterioration, prompting
the first plan for a tunnel bypass.
Mr. DeFebo said the existing tunnels need to be replaced
because of their age, traffic congestion and crashes. “Two lanes in each
direction is not enough capacity,” he said.
On the Sunday after Thanksgiving, eastbound traffic was
backed up eight to 12 miles from the tunnel entrance for about eight hours, he
said.
Widening the existing tunnels would disrupt traffic for
at least five years and pose safety hazards to travelers and construction
workers and “is not an option,” Mr. DeFebo said.
Other reasons that turnpike officials opted for the “cut”
option in 1996: Having a tunnel requires hazardous materials trucks to exit the
turnpike and use alternate routes for the 36 miles between Somerset and
Bedford. The tunnels must be temporarily closed several times a year so workers
can remove giant icicles that form on the walls.
Source: Pittsburgh
Post Gazette
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