The Light at the End is a Tunnel

Digging the 710 underground is a feasible first step toward relieving freeway congestion

For years, we’ve known that connecting the 710 and the 210 – the Long Beach Freeway and the Foothill Freeway – would significantly reduce congestion in Los Angeles and throughout the region. But building a freeway through South Pasadena is a political nonstarter, so nothing has been done.

At long last we have a win-win solution to this 30-year battle: A new feasibility study, funded by the Los Angeles County Metropolitan Transportation Authority, confirms that a tunnel beneath South Pasadena would be a physically, financially and environmentally feasible way to fill the controversial missing link on the 710. Both South Pasadena residents, who don’t want their community split in two, and Los Angeles drivers, who need better mobility, would benefit from the tunnel solution.

Even so, for many, the idea of a $3-billion tunnel seems outlandish: Has anyone done anything like this before? Would such a tunnel be safe? Might it turn out to be another financial boondoggle like Boston’s Big Dig, which went about $10 billion over budget? These questions all deserve careful answers before we decide whether to proceed with such an ambitious project.

Has anyone built tunnels as long as this?

The proposed twin 4.5-mile-long tunnels would be the longest in the United States, but they’d be pikers compared with what other countries are doing. Norway’s Laerdal Tunnel, which connects Oslo to Bergen without a ferry ride, is more than 15 miles long, and Switzerland’s Gotthard Tunnel is 10.5 miles long. Austria and Italy are in the initial stages of constructing a 35-mile-long rail tunnel beneath the Brenner Pass in the Alps.

And much like residents who rightfully want to preserve South Pasadena, Paris has turned to tunnels to preserve part of its history. Paris is completing a missing link on the much-traveled A86 ring road by means of a 6.2-mile-long, double-decker tunnel that will go under, not through, Versailles.

Is tunneling too risky for earthquake country?

Many civil engineers say that during an earthquake they would rather be in a deep-bored tunnel than on a freeway with elevated sections and overpasses. Well-engineered tunnels shake less than aboveground structures. Seismically active Tokyo has made good use of tunnels, and so have transit agencies such as the Bay Area’s (which sustained only minor damage during the 1989 Loma Prieta earthquake, compared with bridge and freeway failures) and our own MTA, notably the Red Line and the Gold Line Eastside Extension.

What about the risk of huge cost overruns, a la the Big Dig?

This is a concern with all such mega-projects. That’s why most of them are now structured so that private investors build the projects at their own financial risk, under long-term agreements that allow them to recoup their investments through tolls. This model has been used for most of Australia’s tunnels and toll roads and for nearly all the tunnel and toll road projects in France.

And this is likely to be the model required to build the 710 Freeway tunnels. But the private sector appears ready to bear the upfront costs.

Secretary of Transportation Norman Mineta recently said, “Every private-sector investment group that we talk to says that California – and Southern California in particular – is the most attractive investment opportunity in America, if not the world.” Congress and the U.S. Department of Transportation are encouraging states to use tolls to help fund major projects on the interstate system, and a project such as the 710 Freeway tunnels is likely to qualify for special fast-track assistance under the Transportation Department’s new National Strategy to Reduce Congestion.

The benefits of building the 710 Freeway tunnels would be enormous. California Department of Transportation engineers believe that connecting the 210 and the 710 would reduce congestion on the country’s most congested freeway system – in part by routing some traffic away from downtown L.A. – saving commuters tens of millions of dollars a year in time and fuel. The tunnels would also greatly increase the connectivity of the freeway network. A missing link in the freeway system is like a break in the Internet — when trouble occurs on the network, it’s important to have multiple alternative paths to route around the trouble. And reduced congestion means reduced emissions. Instead of stop-and-go traffic that hurts air quality, drivers would be moving at low-emission speeds.

One project like this is not going to solve L.A.’s massive traffic congestion problem. That will take decades to achieve, with carefully selected investments like the planned truck-only lanes from the L.A. and Long Beach ports to the Inland Empire. But the 710 Freeway tunnels are a major, doable first step.

Robert W. Poole, Jr. is an engineer and the director of transportation studies at the Reason Foundation. He has advised the last four presidential administrations on transportation issues. An archive of his work is here and Reason’s transportation research and commentary is here.