Caltrans Working To Smooth Out Part Of State Route 52
Tuesday, September 22, 2020
Photo by KPBS Staff
Work is underway to fix a problem that's plagued a portion of state Route 52 for decades.
A little more than a mile of the highway between the state Route 163 and Interstate 805 was built over a landfill, so it’s been in a constant state of settling for decades.
It feels like a rollercoaster going over that portion of the highway.
Caltrans has smoothed it out over and over, but none of those fixes have solved the problem long-term. Now, they’re trying something different.
It’s called compaction grouting.
The process involves drilling more than 4,000 holes, each six-inches in diameter. Caltrans engineer Shawn Rizzutto said pipes are then put into the holes.
“And then we start pumping grout or cement and sand and we create these grout columns which stiffen the roadbed and it doesn’t allow for as much settlement," he said.
The $16 million project is expected to be complete by Christmas.
Rizzutto said they tried the same method on a smaller section of SR-52 nearly four years ago and it’s held up well. They hope this much larger project will make the SR52 rollercoaster history, for good.
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