Easing traffic congestion in south Napa County, the focus of a yearlong Caltrans-funded study, may cost more than $349 million and take 20 years, the Napa County Transportation and Planning Agency reported Monday.
The draft Highway 29 Gateway Corridor Improvement Plan calls for expanding the highway from four to six lanes from American Canyon Road to Highway 12/Jameson Canyon, as well as new interchanges at Highway 12/Jameson Canyon and Highway 221 and improvements to the juncture of 29 and Highway 12/Carneros Highway.
In American Canyon, the two new lanes would be built as frontage roads to siphon off local traffic from the highway.
The plan also adds miles of bicycle paths and sidewalks, and a link to the future Vine Trail multi-use path that’s planned to run from Calistoga to the Vallejo Ferry.
The character of the 17-mile stretch of roadway — from the Vallejo ferry to Trancas Street in Napa — would transition from landscaped freeway to “boulevard” in American Canyon to rural highway further north to align with the residential, commercial and undeveloped surroundings.
The study, which was presented Monday night at American Canyon City Hall, assumes complete implementation will take 20 years or more. Funding sources for the big project are yet to be determined.
The study rules out a sunken or elevated highway through American Canyon as too expensive and restrictive to local residents and businesses.
American Canyon Councilmember Ken Leary generally liked the plan, with the caveat that it won’t make everyone happy.
“The needs (of commuters, tourists and residents) aren’t congruent. They don’t match up. It doesn’t seem like there’s going to be a perfect fix for everybody,” Leary said.
Ray Marcus, a longtime American Canyon resident, said he has long favored a six-lane solution.
“It’s going to make American Canyon a nice drive-through, which I think is exciting,” Marcus said.
Napan Lou Penning said he supported the study, but was skeptical about possible solutions.
“(The drive through American Canyon) is always going to be miserable. It’s always going to be slow,” Penning said.
St. Helenans David and Leslie Moreland objected to the proposed “flyover” Soscol interchange that, while eliminating a traffic light, would block the direct connection between Highway 221 and Soscol Ferry Road where the Morelands have a business.
David Moreland described the flyover plan as outdated, developed by Caltrans 15 years ago. That configuration, the couple said, would reduce the effectiveness of newly extended Devlin Road, rerouting trucks and other traffic through the Napa Valley Commons industrial park and creating potential tie-ups for Costco shoppers and residents in the planned Napa Pipe development.
One big item missing from the cost estimate is land acquisition needed for widening the highway for additional lanes. In American Canyon alone an estimated two acres would be required to implement the “modified boulevard concept,” the design favored by several city council members.
Most of the plan’s revisions to Highway 29 would occur between American Canyon Road in American Canyon and Highway 12/Carneros Highway, just west of the Napa River’s Butler Bridge.
Improvements to Highway 29/Sonoma Boulevard in Vallejo could include an additional northbound lane as one of several options.
A second public presentation was scheduled for 6 p.m. Wednesday in Napa at the Napa County Transportation and Planning Agency offices on Burnell Street for more feedback. The plan and public comment are supposed to go before the study’s Steering Committee on Feb. 19, with final approval by late spring
The complete draft is online at nctpa.net/sr-29-corridor–study.