This is Kevin Roderick with LA Observed for KCRW.
On a big summer weekend this July, Southern California will experience a rite of passage. A major milestone in our transportation history.
And I don't mean the opening of the Expo Line. No rail link in Southern California can compete with this.
The big deal is that after midnight on a Friday night, the San Diego Freeway will close in the Sepulveda Pass. All lanes, in both directions.
The 405, as many drivers know it, will stay closed all weekend – until Monday morning rush hour.
The closure is part of the massive freeway widening and modernizing project that has been frustrating – and frightening – drivers on the Westside for the last year.
Regular commuters have been watching the lanes shrink and the freeway shoulders vanish with a mix of dread -- and fascination.
They – and I'm one of them – are intrigued on the one hand by the appearance of new concrete structures that don't go anywhere. And the sight of new retaining walls in the canyons of Sepulveda Pass.
But we also worry that the whole mess is going to get a lot worse before it gets better.
That's what's going to happen on that Friday night in July.
To build new modern bridges designed to not fall down in earthquakes -- and to carry more cars – crews have to tear down the old bridges.
Giant destruction machines have been munching away at the lesser bridges, like the one that carries Sunset Boulevard over the freeway.
But the Mulholland Drive bridge is an engineering challenge.
You've seen it at the crest of Sepulevda Pass, marking the line between the cool air of the coast and the oven that's the valley in summer.
The bridge is tall and kind of majestic. But its steel and concrete are old, dating from 1960.
To be safely removed, a half million drivers who typically creep over the pass on a summer weekend will have to find another way.
To get ready, Caltrans and Metro plan to flood the airwaves and the web with warnings. Advice to take another route, or stay home.
They're worried enough about the disruption that the media blitz is starting now, two months early.
It's easy to see why. The numbers of people affected are huge. The half-million cars and trucks and motorcycles that use the 405 on a weekend carry a lot more people than use all the train lines in the LA area combined.
The disruption is manageable, Metro says, as long as the public cooperates.
Officials are basing the behavior modification campaign on the 1984 Olympics. So much fear was circulated about traffic jams that people altered their behavior and the games went off almost without any traffic snarls at all.
Whatever happens the weekend of July 15 will be a good test of our ability to adapt. To go with the flow.
That's because we'll have to do it all over again a year later when they dismantle the rest of the Mulholland Bridge.
For KCRW, this has been Kevin Roderick with LA Observed.
Banner image: The Mulholland Bridge, finished in 1960, comes down in July, prompting a 53-hour freeway closure.