PLEASANTON, Calif. (KGO) -- It is busy on freeways in and around the tri-valley.
That's because southbound I-680 from Dublin to Sunol was shut down due to construction.
This is just one phase of a multi-year project that is underway.
But will it reopen ahead of Monday's morning commute.
Saturday evening traffic backed up quickly from San Ramon into Dublin as four lanes merged into one.
"Traffic is terrible," said one driver on the road.
In the works is a three-year project, which includes repaving a three-mile stretch of southbound I-680 this weekend between Dublin and Sunol.
"We want to pretty much, want to condense 40 nights of, into just a weekend," said Caltrans Spokesperson Pedro Quintana.
Quintana says crews are working around the clock this weekend to upgrade the far right lane.
On Friday night, crews ripped out the old pavement. On Saturday night, they began laying down the new foundation.
"If you go out there on that road pavement, you'll understand that, that road has reached its end-service life. We hear it from motorists, we hear it from other people who live around the Bay Area," Quintana said.
Quintana says shutting down the freeway makes it safer for crews to do the work - and possibly quicker.
As of Saturday night, he says they are on schedule to complete work before the Monday morning commute.
"The concrete pour takes about 12 to 18 hours to solidify. When all is said and done, we do the cleanup, then we do the stripping," Quintana said. "We will be ready and on schedule to reopen southbound 680 by the Monday morning commute."
Caltrans says the entire I-680 Express Lane project between Dublin and Sunol will also add new lanes to both sides of the freeway, including express lanes. It is estimated to be completed by early 2025.
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