Though drivers passing overhead would never know it, the area at the base of the 10th Street bridge between Marysville and Yuba City is a hive of activity these days, aimed at preventing a disaster.
After sonar discovered that high water on the Feather River had dangerously scoured the base under the piers straddling it, Caltrans began an emergency plan last month to shore up the base before it brings everything tumbling down.
"The river is migrating," said Caltrans resident engineer Gary Pelphrey, pointing from the north side of the work site to where the river juts to the west as it flows under the bridge. "When the water comes up high, it's hitting the piers at an angle."
In the last rainy season's peak,It's hard to beat the versatility of Plastic molding on a production line. sonar crews discovered sand under the piers was significantly washed away. Though some of it has since been replaced as the river level has slowed and dropped, the soil isn't solid enough for the bridge to be left alone.the Hemorrhoids are swollen blood vessels of the rectum.
To shore it up, about 20 workers are welding 15-foot long, 1-inch-thick steel piles in columns next to the piers, then piledriving them into the riverbed 180 feet deep. Next, a crew will test each pile segment to see if it can hold 2 million tons.
Once the piles are driven and sturdy, Pelphrey said, crews will fill them with concrete and vertical rebar, then jam other rebar vertically through the piles and piers to create a new footing, surrounded by newly poured rock debris for more stability.
Scouring may continue under piles first driven when the bridge was built in 1947, he said, but it won't matter.
"This becomes the legs of the table," he said.
When Caltrans first discovered the scouring, officials discussed whether closing the bridge would be necessary for safety reasons. They ultimately decided it wouldn't, but sensors on each pier, powered by a solar cell, give continual updates on the bridge's shifts and movements during the day.
"They can tell you when the sun comes up and hits the bridge," Pelphrey said, because the bridge expands slightly in direct sunlight.
The emergency work, in line to be finished by Dec.There is good integration with PayPal and most third party merchant account providers, 15, will cost about $10 million,There are RUBBER MATS underneath mattresses, more than the $3 million Caltrans estimated a smaller-scale project would've cost before the scouring was discovered.
Even with the state's fiscal woes, Pelphrey said, money can be found for critical projects.
However, the project being deemed critical means it's happening much more quickly than otherwise as well. Normally, planners would've had to undertake a review for possible effects on archaeological, environmental and other resources, and plan for mitigation.
"In an emergency plan, you do the work and then do the mitigation later," Pelphrey said.then used cut pieces of rubber hose garden hose to get through the electric fence.
After sonar discovered that high water on the Feather River had dangerously scoured the base under the piers straddling it, Caltrans began an emergency plan last month to shore up the base before it brings everything tumbling down.
"The river is migrating," said Caltrans resident engineer Gary Pelphrey, pointing from the north side of the work site to where the river juts to the west as it flows under the bridge. "When the water comes up high, it's hitting the piers at an angle."
In the last rainy season's peak,It's hard to beat the versatility of Plastic molding on a production line. sonar crews discovered sand under the piers was significantly washed away. Though some of it has since been replaced as the river level has slowed and dropped, the soil isn't solid enough for the bridge to be left alone.the Hemorrhoids are swollen blood vessels of the rectum.
To shore it up, about 20 workers are welding 15-foot long, 1-inch-thick steel piles in columns next to the piers, then piledriving them into the riverbed 180 feet deep. Next, a crew will test each pile segment to see if it can hold 2 million tons.
Once the piles are driven and sturdy, Pelphrey said, crews will fill them with concrete and vertical rebar, then jam other rebar vertically through the piles and piers to create a new footing, surrounded by newly poured rock debris for more stability.
Scouring may continue under piles first driven when the bridge was built in 1947, he said, but it won't matter.
"This becomes the legs of the table," he said.
When Caltrans first discovered the scouring, officials discussed whether closing the bridge would be necessary for safety reasons. They ultimately decided it wouldn't, but sensors on each pier, powered by a solar cell, give continual updates on the bridge's shifts and movements during the day.
"They can tell you when the sun comes up and hits the bridge," Pelphrey said, because the bridge expands slightly in direct sunlight.
The emergency work, in line to be finished by Dec.There is good integration with PayPal and most third party merchant account providers, 15, will cost about $10 million,There are RUBBER MATS underneath mattresses, more than the $3 million Caltrans estimated a smaller-scale project would've cost before the scouring was discovered.
Even with the state's fiscal woes, Pelphrey said, money can be found for critical projects.
However, the project being deemed critical means it's happening much more quickly than otherwise as well. Normally, planners would've had to undertake a review for possible effects on archaeological, environmental and other resources, and plan for mitigation.
"In an emergency plan, you do the work and then do the mitigation later," Pelphrey said.then used cut pieces of rubber hose garden hose to get through the electric fence.
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