The California Department of Transportation (Caltrans) continues to move forward with the Antlers Bridge Replacement Project, which will replace Antlers Bridge on Interstate 5 in Shasta County over the Sacramento River arm of Shasta Lake. Construction began in October 2009, and the five-year effort is just over 50% complete. The five-span concrete bridge will be 1,942 ft long and 104 ft wide. It is being constructed on a new parallel alignment just east of the existing bridge. In addition, a 0.4-mile-long section of highway south of the bridge will be realigned. The existing 1,330-ft-long structure is scheduled for demolition.
Caltrans, along with the Federal Highway Administration, awarded the $125 million contract—43% below the engineer’s estimate—to Tutor Perini of Sylmar, Calif. It is financed with federal and state transportation money through the State Highway Operation and Protection Program.
Caltrans is documenting the project with two EarthCam MegapixelCam systems. Each provides a unique perspective of the construction progress. The MegapixelCam captures high definition snapshots of the progress that are suitable for time-lapse photography. The 6.3-megapixel, high-definition fixed-position cameras take live snapshots in addition to providing 15-minute archives. Digital presets and pan/tilt/zoom options are all provided in the captured images.
“We want to keep the public and all resource agencies up-to-date,” said Eric Akana, project manager with Caltrans. “We want to be as transparent in construction as possible. The project is in a recreation area and the surrounding land is all owned by the U.S. Forest Service. Obviously, environmental impact is very important. The cameras give us visual tools to validate claims and address public concerns and comments. The images help us explain what we’re doing and why.”
Akana also says that the cameras also help Caltrans with project scheduling. The historical weather information that is archived by the camera systems is a valuable tool for the agency. Since Shasta Lake can fluctuate in depth up to 100 ft, this information represents added value.