The tunnel passed all the critical tests on Friday to ensure it will open this weekend. ABC7 News has been following the progress over the past four years.
Passing cars have been honking and cheering as they go by, clearly excited by the prospect of this tunnel opening very soon. Caltrans estimates that this new bore will save individual commuters at least 12 minutes of idling per day. That should end after Saturday when four lanes will be permanently dedicated in each direction.
Caltrans estimates that the new bore will save individual commuters at least 12 minutes of idling per day, especially those who go in the reverse direction.
"I've been driving this road since 1980," said Dr. Larry Diller, a reverse commuter.
For more than three decades, East Bay pediatrician Diller has done everything he can to avoid the long backups at the Caldecott Tunnel by using the side roads.
"It was my secret route. I would tell certain patients coming from San Francisco or from this side of the tunnel about it, but I wouldn't tell anybody else," said Diller.
Diller lives in Piedmont and commutes to his office in Walnut Creek daily. He's a reverse commuter -- one who is drives the off-peak direction, with just two lanes, going his way morning and night. He told us he has commuted to Walnut Creek 15,800 times over 33 years.
Finally, like so many reverse commuters, Diller is about to get some big relief once the new 4th bore of the Caldecott opens. He and tens of thousands of others can abandon the daily quest for shortcuts.
"The primary purpose of the Caldecott 4th Bore is to relieve traffic congestion in the off-peak direction," said Ivy Morrison from Caltrans.
That's not to say that Diller doesn't appreciate all he's learned over the years. He even took a look at a study published in the New York Times magazine about the psychology of commuting, with a particular focus on the Caldecott.
"As a paradigmatic question: Are you an early merger when the sign says merge right, or are you a left-laner, like I was? And the question is what's the right thing to do? As it turns out, mathematically, it makes sense to use all the available lanes up to the mouth of the tunnel," said Diller. "The wonderful thing about the 4th bore is I won't have to play these games anymore. I can just get right on 13 and go right to the tunnel, I hope."