O.C. Jones & Sons delivered this summer Segment 2C of the California Department of Transportation's (Caltrans) Konocti Corridor Project — the $85 million first phase that widens a 3-mi. segment of State Route 29 from one lane in each direction to a four-lane highway.
Planning is now ongoing for the second and third phases of the project along an 8-mi. section of SR 29 between Lower Lake and Kelseyville in Lake County to improve safety for motorists. The combined cost of the remaining two segments is approximately $200 million.
This project is a cooperative effort among Caltrans, the Lake County Area Planning Council (LAPC) and the Federal Highway Administration (FHWA), which provided the initial construction funding. The partners are working to secure funding to complete the project.
"While we are grateful for the completion of the first phase of the Konocti Corridor safety project, we are still not done," said Jaime Matteoli, Caltrans corridor manager.
Segments 2A (3 mi.) and 2B (3 mi.) are east of 2C.
Segment 2B is in the design and right-of-way phases.
"The department is currently seeking funding for construction on Segment 2B," said Manny Machado, a Caltrans spokesperson. "Segment 2A is only funded through the design phase. In the event Segment 2B is successful in obtaining construction funding, construction is targeted to begin in 2028."
Lake APC Executive Director Lisa Davey-Bates, who has worked on the project for 23 years, stressed the importance of the partnerships that enabled the project to become a reality.
"From the start, it's been a long, but rewarding process," she said. "Since 1988, there has been a team of experts working together on this project to provide a safer and more efficient roadway network for motorists, cyclists and pedestrians in Lake County."
"Completing the first phase of the Konocti Corridor Project advances the long-term vision for a brighter future for Lake County and all Californians," said Matt Brady, Caltrans District 1 director.
The corridor serves the communities of Lakeport, Kelseyville, Lower Lake and Middletown, as well as auto and commercial truck traffic traveling between U.S. 101 and Interstate 5.
"With anticipated traffic growth, by expanding the section of highway to four lanes with controlled access, capacity will be increased, and highway safety will be significantly improved," Machado said. "In addition, the new expressway will assist in achieving the long-range plan to divert traffic from communities on the northern end of Clearlake, where pedestrian and non-motorized traffic safety have been an ongoing concern."
The traffic management plan was based on lane closures and detours.
O.C. Jones was awarded a construction contract in November 2019 to create the four-lane expressway (two lanes in each direction), with 10-ft.-wide shoulders outside and 5-ft.-wide shoulders next to the inside lanes. There also are acceleration and deceleration lanes and new intersections that connect to new frontage roads that replace driveways connected to the highway. Sections of the existing road, some of which have medians, were realigned.
This was a primarily day-shift operation.
Clearing and scrubbing operations, which took several weeks, removed trees and shrubs.
Excavation and site prep operations took place on both sides of the existing lanes simultaneously. Equipment operators at many locations had ample space to maneuver their vehicles and place materials required for the subbase and base for the new lanes and shoulders.
Excavators removed dirt and rock, which included larger boulders. In several places, excavated material was used as fill to build up sections for the exterior lanes between 8 and 5 ft., which were then compacted.
This work involved large excavators, dozers and a John Deere mini excavator that pushed rock fill into 5-ft. wide trenches dug by an excavator with a bucket that was accompanied by various-sized loaders.
With traffic using the existing lanes, the paving crews placed asphalt topping for the new lanes simultaneously.
The paving was based on completing defined sections. Loaders and other trucks drove along an existing lane, with asphalt placed on the adjacent lane by a Weiler remixing transfer vehicle.
A few hours later, asphalt would be placed for the second new lane. The work was reliant on a screed guided by a crew member who was approximately 20 ft. ahead of the machine.
Crews also installed underground infrastructure and drainage infrastructure. CEG
(All photos courtesy of Caltrans.)
