Tunnel Resurfaces as 710 Freeway Extension Plan

Times Staff Writers

Some transportation officials say they may have the answer to ending the decades-long opposition to completing the Long Beach Freeway: Build it underground.

Tonight, the MTA and Southern California Assn. of Governments will present the idea to the South Pasadena City Council, longtime opponents of extending the freeway through their city.

“There could be a lot of win-wins on this whole issue,” said Mark Pisano, executive director of SCAG, who will make the presentation along with Roger Snoble, chief executive of the Metropolitan Transit Authority, and Assemblywoman Carol Liu (D-La Canada Flintridge).

Using European models, Pisano said, a tunnel could be built -- perhaps for less money than a regular freeway -- to connect the Long Beach Freeway, which ends in Alhambra, with the Foothill Freeway in Pasadena. An above-ground freeway would slice through those cities, as well as South Pasadena and the El Sereno area of Los Angeles.


Few specifics are available about the tunnel plan, but reports have said it would be approximately 150 feet below ground and possibly wide enough to accommodate six lanes. Exactly how many, if any, on- and offramps it would have, and whether the entire 6.2-mile extension would be tunnel, would still have to be resolved.

The idea of a tunnel built with the latest construction technology has been whispered about for months and has been gaining momentum over the last few weeks.

Staff members from the MTA met Monday with Alhambra officials to give them a brief overview of the plan. Tonight’s presentation, said City Manager Sean Joyce, is in part to “legitimize the discussion by raising the possibility in a public forum, allowing South Pasadenans to come to grips with it.”

The MTA wants to conduct preliminary feasibility studies on such a tunnel, and Snoble, Pisano and Liu are asking the South Pasadena council not to oppose such studies.


The freeway extension, first proposed more than 30 years ago, has been held up by lawsuits, lobbying and legislation, which so far have managed to block completion of the freeway.

Funding for a freeway extension, estimated to cost as much as $1.4 billion, would have to be procured from many sources, including federal and state funds that are being trimmed because of the budget crisis. Some transportation experts say it is unlikely that the project would ever secure the funds necessary to be completed.

Tunneling, said South Pasadena Mayor Harry Knapp, has come up before in discussions about the freeway. It was considered as recently as 11 years ago, he said, but “it got laughed off because of cost.”

Now, Pisano said, “the whole cost structure has been significantly altered” by cost-effective tunneling projects in Europe. He cited examples of roadways in France and the Netherlands.

Robert Poole Jr., president of the Reason Foundation, said the idea of a tunnel to connect the Long Beach Freeway to the Foothill Freeway was the subject of an informal feasibility study by the foundation five years ago. The study estimated that the project would cost $2 billion to $3 billion, with some expenses reimbursed by charging tolls.

“It’s an entirely feasible thing to do,” he said.

James Moore, a USC professor of civil engineering, disagrees. He suggests a more cost-effective approach would be to build the freeway at the bottom of a massive ditch along the length of the route, then cap it with soil -- a technique called “cut and cover” that has been considered for the 710 before.

To determine whether the tunnel makes sense financially, said Steve Roop, a research scientist with the Texas Transportation Institute, local officials would have to compare the construction costs against the time and money saved by motorists in the region over 50 years or so.


“Any time the surface gets congested, the economics of going underground improves,” said Roop, who is working on a freight-moving tunnel between Dallas and Monterrey, Mexico.

Venting the automobile exhaust from a freeway tunnel is fairly simple, but the tunnel project could run into problems if the designers find seismic faults or drainage problems, he said.

A similar project underneath Boston, a 10-lane, 7.5-mile interstate nicknamed the Big Dig, is estimated to come in at more than twice the $6.4-billion budget approved by Congress in 1987. Stymied by engineering obstacles, lawsuits and contract disputes, the project has taken more than a decade to build. State taxpayers and toll-road drivers will bear the brunt of the cost increases.

Although funding will perhaps be the ultimate arbiter of the 710 project, Pisano said that, from his perspective, success may depend on how the project is received by the cities it would pass through.