The sinkhole that appeared a few miles south of Grass Valley and threatened the viability of Highway 49 has been contained and is being managed, transportation officials said.
“There has been no traffic interference,” said Rochelle Jenkins, a spokeswoman for Caltrans. “We’re lucky to have a third lane in the area.”
The sinkhole first developed Dec. 5 after a foot of rain hammered the area over a four-day period.
“There was a huge amount of water that fell in a short amount of time,” Jenkins said.
The rushing water found its way into a crack in a culvert alongside the road. The crack became a void, causing the culvert to fail and create a deep sinkhole.
Workers have delved about 30 feet down into the hole in an attempt to reach the bottom, but even with head-lamps, they still have not seen the bottom of the pit, Jenkins said.
Although it is deep, the sinkhole is not wide, as it spans a 10-foot-by-10-foot area, Jenkins said.
Caltrans engineers have inserted a cement slurry on the highway-side of the hole to bolster the surrounding land and prevent the hole from widening. Steel reinforcement bars have also been implemented.
Repair work on the sinkhole will last for at least another month, located a mile north of the massive Caltrans transformation of the La Barr Meadows intersection.
More than 7,400 people are estimated to drive along Highway 49 daily, heading to work in Placer, Sacramento and other nearby counties.
To contact Staff Writer Matthew Renda, email firstname.lastname@example.org or call (530) 477-4239.