In the US, where politicians are in constant gridlock over the nation’s budgets, tunnel projects are still moving ahead. Despite cancellations and anti-tunnel initiatives, there is plenty of demand for underground construction. In Canada, where politics can change more rapidly, in comparison to its southern neighbour, a new mayor may mean the industry will be busier in years to come.

New York
New York City has seen several milestones already this year on two subway projects. A Skanska/Schiavone/Shea joint venture completed the first of two bores for phase one of the Second Avenue Subway, and has started mining the second. This particular phase for the two-track 8.5mile (13.7km) line running below Second Avenue, includes new stations at 96th, 86th and 72nd Streets. Phases two through four will complete the north-south running line, starting from 125th Street in Harlem, running to Hanover Square in Lower Manhattan, with 16 new stations in total.

The second project is the East Side Access for the Long Island Rail. Work is underway in both Queens and Manhattan to complete tunnels either side of an existing 2.6km long stretch at 63rd Street. On the Queens side of the project, a joint venture of Granite Construction Northeast/Traylor/Frontier-Kemper has just this spring started mining the 3.2km of tunnels using slurry TBMs. A joint venture of Dragados/Judlau is constructing the 2.2km Manhattan Approach Tunnels and caverns beneath Grand Central Station.

“There is an incredible amount of underground work in New York,” says Greg Kelly, president of infrastructure at Parsons Brinckerhoff. There is always a need for expanding capacity and for rehabilitating tunnelling assets, whether that demand is coming from the water or transportation markets,” he explains.

What was set to be another mega project for the area, the USD 8.7bn Access to the Region’s Core (ARC) tunnel, met its demise though the (budgetary) axe-wielding New Jersey governor, Chris Christie. He cancelled the tunnel in October 2010 citing concerns of potential cost overruns. Other alternatives have been speculated, but nothing as concrete as Amtrak’s February announcement of the Gateway Project. The rail operator will spend USD 50M on preliminary engineering and design for two new trans-Hudson rail tunnels from Penn Station in Newark, New Jersey, to an expansion at Penn Station in New York.

“While the governor of New Jersey made the decision to stop the project, the need to solve capacity across the Hudson River remains. And so it’s interesting and, in a sense, reassuring to everyone—including the governor,” Kelly says. “We need to still deal with these kind of issues. While ARC was stopped, it doesn’t mean that those in political positions are not prepared to deal with it. They’re just looking at different solutions to solving the problem of trans-Hudson capacity.”

Seattle
In Seattle the end result isn’t capacity, it’s creating a replacement for the double-deck Alaskan Way Viaduct, which is deteriorating. But many of the arguments from those opposed to the bored tunnel solution are similar; fear of cost overruns, an aversion to spending while state and federal governments are strapped for cash and environmental concerns.

In January, a joint venture of Dragados/Tutor Perini signed a USD 1.35bn contract with the Washington State Department of Transportation (WSDOT) to design and build the two-level, 1.7-mile (2.7km) bored tunnel that will replaced the Alaskan Way Viaduct in Seattle. Following the project’s environmental review expected this summer, the JV will begin final design and construction of the bored tunnel; or maybe not.

Two anti-tunnel groups have gathered enough signatures for their two separate initiatives to be on an August ballot. One would prohibit use of the city’s right-of-way for the tunnel project. The other measure is a referendum for Seattle citizens to affirm or repeal the right-of-way agreements the city made with WSDOT. The city attorney, Pete Holmes, has declared this referendum illegal and is trying to put it before a judge. And a third group, supporting the tunnel, has retained a lawyer, Paul Lawrence, to support him.

Holmes and Lawrence say both initiatives are not legal because they are being applied to administrative actions, not policy decisions.

The rift between supporters and opponents has the pro-tunnel governor of Washington and Seattle City Council pitted against the anti-tunnel mayor of Seattle. It is safe to say the tension will continue to rise in Seattle as the year draws closer to August, which marks not only the votes but also the estimated start date for construction on the tunnel.

But it’s not all bad news coming out of Seattle. Progress is being made on the 3.15 mile (5km) University Link light rail extension. These twin bore tunnels will run north from the city’s downtown to the University of Washington. Three TBMs with 21ft (6.4m) diameters, will be delivered by May, for excavation to start this summer. A joint venture of Traylor/Frontier-Kemper is using two Herrenknecht TBMs, each doing an 11,300ft (3.4km) drive from the UW station to the Capitol Hill station. The JCM U-Link joint venture of Jay Dee/Coluccio/Michels is using one Hitachi-zosen machine for the tunnels between Capitol Hill Station and Pine Street Stub Tunnel, a distance of approximately 1.15 miles (1.85km).

Toronto
The tunnelling market in Canada is very vibrant and active, says Rick Staples, president of the Tunnelling Association of Canada. Large urban areas like Toronto require tunnels for rapid transit and utilities, while some other areas of the country are seeing an active market for hydroelectric power plants.

“There has always been a demand for tunnelling, but it varies with the economic and political climate,” Staples says. “Right now we’ve got governments that have seen action is required so they’re coming to the table and funding some of these things.”

In Toronto, the 8.6km Toronto-York Spadina Subway extension with six stations is in the initial stages of construction. Contractor Aecon, with McNally and Kiewit, is getting ready to launch the first of the project’s four Lovat EPBMs and start mining on the project’s southern tunnels at the end of May.

Earlier this year, Toronto Transit City awarded OHL the northern tunnels package. There is also a series of LRT expansion programmes in various forms of design and a preparation for construction, which involves many kilometers of underground construction. Though that wasn’t always the plan.

Elected in autumn 2010, the city’s mayor, Rob Ford, ran on a campaign championing underground solutions. In March he announced a revised, CAD 12.4bn (USD 12.9bn) transit plan for Toronto that does just that.

The Eglinton-Scarborough Crosstown LRT, a single line running 25km, that was previously planned as mostly above ground, has been changed to one that will be largely below ground.

In addition to the transportation work, there are also large diameter sewer extensions in the works for Toronto, according to Staples. “Probably sometime next year we’ll have in the order of 10 to 12 TBMs operating simultaneously on various tunnelling projects.”


The Seattle seafront and Alaskan Way Viaduct One of the TBMs for the York Spadina extension