Mention the Interstate 580 freeway and the image that comes to mind is almost always the Galena Creek Bridge.
At 1,725 feet long and 300 feet above the creek at its highest, the bridge is the most prominent feature of the project that will complete the freeway between Reno and Carson City.
It is the focus of critics, particularly in Las Vegas, who believe the more than $400 million total for the project should have been used in the south. And the difficulty of raising the arches that will support the bridge was the reason the original contractor, Kraemer and Sons, pulled out of the contract.
The new contractor, CC Myers, is getting around that problem by filling in most of the Galena Creek valley with dirt, which will be removed after the bridge is finished.
To prepare for that, the company is building a 44-foot diameter, 400-foot-long concrete arch over the creek so it can continue to flow. The valley will then be filled to 120 feet below the roadway and falsework, a temporary structure of steel beams and columns, will be installed. The concrete and steel road will be built atop the falsework, which is removed when the job is done.
NDOT assistant resident engineer Brad Durski said that avoids the dangers Kraemer engineers saw in building the 700-foot arches in half-sections on the ground, then raising them into place. He said they were concerned the attempt could turn into a disaster if a strong gust of wind grabbed one of the arch sections.
When everything is done, Durski said, the fill will be removed and the tiny creek restored to its native state.
He said to do the job the contractor will have to move 4 million cubic yards of dirt.
"That's 40,000 concrete trucks completely full," he said.
But they won't be using trucks. Durski said to move that massive amount of fill, a 3,000-foot-long conveyor system will be installed. They expect to use the same conveyor to take the dirt back out.
• Contact reporter Geoff Dornan at firstname.lastname@example.org or 687-8750.