It's an elusive missing link in Los Angeles' freeway system: A 6.2-mile dotted line on the map that transportation planners have for decades hoped would connect the Foothill Freeway in Pasadena with the Long Beach Freeway in Alhambra.
But that dotted line runs through a historic neighborhood of California Craftsman homes and tree-lined streets in South Pasadena. For nearly 50 years, residents there have fought the freeway. Just as tenaciously, residents of nearby traffic-weary cities, particularly Alhambra, have battled to have it built.
Now, some officials believe the solution to the standoff might lie beneath their feet. Earlier this month, they persuaded Congress to approve $2.4 million to study the possibility of extending the freeway through a five-mile, $2-billion tunnel that would run under South Pasadena and part of Pasadena.
The idea of building the longest continuous highway tunnel in the United States by digging under one of the country's most crowded metropolitan regions may seem far-fetched.
Even if the feasibility study points the way forward, years of environmental impact reports, engineering plans and financial wrangles would remain. But supporters of the tunnel -- driven in part by a near-desperate desire to end the fighting over the freeway -- believe that several developments make the idea practical.
One involves the subject that rivals traffic as a Southern California obsession: real estate.
Over the last three decades, the California Department of Transportation has purchased more than 500 homes that occupy the potential freeway right of way. Most were bought a generation ago, many for prices in the $50,000 range. One was recently appraised for $780,000. Building a tunnel would allow Caltrans to sell most of the homes, although a change in state law would be needed to sell them at full-market prices.
"We're probably sitting on half a billion worth of property," said Ron Kosinski, Caltrans' deputy district director for environmental planning.
On the other side of the ledger, finishing the freeway above ground would require taking more than 400 homes at a price, including relocation benefits, of about $1 million each, Kosinski estimates. "That's $400 million right there for real estate," he said. "That's a substantial chunk of money."
Combine the real estate with new techniques pioneered in Europe that lower the price of tunneling and the cost to taxpayers of putting the road 100 feet to 200 feet below ground may be not much more expensive than building on the surface, Caltrans officials say.
The tunnel idea has won surprising, though guarded, support from both sides of the battle -- preservationists who see the tunnel as a way to avoid destroying the neighborhood, and traffic-weary residents from Alhambra and surrounding cities.
"At this point in history, the tunnel alternative is the only viable way to explore completion of the 710 Freeway," said Pasadena Mayor Bill Bogaard, "keeping in mind the environmental, political and fiscal difficulties with a project that is approaching its 50th anniversary."
It's just possible, said Rep. Adam Schiff (D-Burbank), who sponsored the $2.4-million study, "that the elusive common ground for the 710 Freeway gap after all these years may be underground."
South Pasadenans have long suspected that a traffic light on Fremont Avenue and Alhambra Road is kept on green for a long time to usher an inordinately large number of cars into their city.
Their opposition to the freeway extension has become a national symbol of historic preservation.
For their part, Alhambrans a few years ago put up street barriers to divert traffic from their streets to South Pasadena -- a move that ended after city officials realized it was hurting their own businesses
"It's like the Hatfields and McCoys," Kosinski said. "They've been on opposite sides for generations or more, so they have that kind of blood pressure-raising perspective on each other."
In South Pasadena, an upscale suburb of 24,000 people located eight miles north of downtown Los Angeles, the tunnel idea is being embraced -- to a point.
"I think the tunnel idea shows a lot of promise," South Pasadena Councilman Mike Ten said. "It addresses age-old concerns about the destruction of neighborhoods and the uprooting of families and loss of very needed housing. It may be the solution all of us can live with."
But some of the staunchest freeway opponents said they smell a trick.
"I think the whole idea of a tunnel is a Trojan horse to get the freeway," said Joanne Nuckols, 62, who drives around town in a Volvo with a "NO 710" license plate. "There are those in town, those who have been around and part of the freeway fight for many years, who believe that this is a bait and switch."