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Miners hug after a giant drilling machine completed the world's longest tunnel beneath the Swiss Alps Oct.15, 2010.(Photo: Fabrice Coffrini, AFP/Getty Images)
GENEVA — Switzerland will celebrate<span style="color: Red;">*</span>an engineering marvel 20 years in the works on Wednesday: the debut<span style="color: Red;">*</span>of the world's longest and deepest railroad tunnel.
The new tunnel through the Alps<span style="color: Red;">*</span>is 35.5 miles long, exceeding<span style="color: Red;">*</span>by 2<span style="color: Red;">*</span>miles the current record-holder, Japan’s Seikan Tunnel. Some sections lie a record<span style="color: Red;">*</span>1.4 miles beneath the mountain's peak.
The tunnel<span style="color: Red;">*</span>will carry 325 passenger and freight trains a day, with each trip taking 20 minutes at speeds up to 150 mph. The goal is to reduce heavy auto traffic that creates pollution.
“We are not showing off,” Transport Minister Doris Leuthard told Swiss Radio International about the<span style="color: Red;">*</span>$8 million grand opening<span style="color: Red;">*</span>expected to draw 100,000 people. That's a<span style="color: Red;">*</span>modest sum to spend to showcase a mammoth project that cost $10 billion and employed thousands of<span style="color: Red;">*</span><span style="color: Red;">*</span>workers.
The tunnel will go through<span style="color: Red;">*</span>7,000-foot<span style="color: Red;">*</span>Gotthard Mountain. The mountain pass<span style="color: Red;">*</span>has long served as Europe's main north-south axis through the Alps, handling 6 million vehicles a year.
Trucks hauling cargo across the continent’s most densely populated area, stretching from the United Kingdom to Italy, inevitably pass<span style="color: Red;">*</span>through the Gotthard, often creating congestion.
A view of the 35-mile railway tunnel under construction under the Alps May 6, 2009.<span style="color: Red;">*</span>(Photo: AFP/Getty Images)
To reduce the environmental impact of cars, the Swiss have<span style="color: Red;">*</span>wanted to shift traffic from the road to rail. In a 1992 referendum, voters approved constructing a tunnel to<span style="color: Red;">*</span>reduce<span style="color: Red;">*</span>transit time, hauling costs<span style="color: Red;">*</span>and air pollution.
Work started in 1996, and the actual excavation<span style="color: Red;">*</span>using giant rolling drills 1,345 feet long and weighing 300 tons was completed in 2010. A<span style="color: Red;">*</span>1,970-foot-long<span style="color: Red;">*</span>machine laid the concrete lining and drainage pipes. And once<span style="color: Red;">*</span>28 million tons of rock were<span style="color: Red;">*</span>removed, workers began to install the<span style="color: Red;">*</span>tracks in two tunnel tubes.
The lengthy time to complete the project was not unusual given its complexity,<span style="color: Red;">*</span>said Kalman Kovari, emeritus professor of tunneling at the Federal Institute of Technology in Zurich and a consultant on the project.
The geology of the Alps<span style="color: Red;">*</span>means the hardness of the rocks vary,<span style="color: Red;">*</span>and “the rate of excavation per day depends on rock quality,” Kovari told USA TODAY. Even with high-performance boring machines, “it was clear that the construction time could not have been reduced substantially,” he added.
Engineers knew from the beginning that tunneling through the mountain<span style="color: Red;">*</span>would not be easy or quick. They’d have to excavate through some<span style="color: Red;">*</span>hazardous zones that had crumbling rocks or potential flooding.
The engineers solved the problem by using steel arches to support the excavation, a<span style="color: Red;">*</span>mining technology used for the first time in an underground tunnel.
Other potential problems had to be tackled before construction could begin. One was that<span style="color: Red;">*</span>temperatures at the deepest spots exceeded 100 degrees. So the<span style="color: Red;">*</span>air had to be cooled to protect 2,600 workers excavating the rock.
Miners wave flags as they celebrate after a drill machine broke through the rock at the final section of the Gotthard Base Tunnel in the Swiss Alps on Oct. 15, 2010.<span style="color: Red;">*</span>(Photo: Christian Hartmann, AP)
“It was also important to protect the workers from accidents,” Kovari said. “Strategies had to be developed to recognize the nature of the rock and to apply the highest industrial mechanization during excavation.”
Passenger safety also was<span style="color: Red;">*</span>a priority. According to AlpTransit, the company in charge of the project, a series of sophisticated emergency evacuation sites<span style="color: Red;">*</span>and alarms are installed along the train route.
The Swiss, known for carefully crafted watches, chocolates and army knives,<span style="color: Red;">*</span>are just as proud of this gargantuan achievement.<span style="color: Red;">*</span>As<span style="color: Red;">*</span>the government boasts<span style="color: Red;">*</span>on its website, the tunnel “symbolizes Swiss values such as innovation, precision and reliability.”
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