There’s a reason that Jameson Canyon Road/Highway 12 is Napa’s most vilified roadway.
Opposing ribbons of high-speed traffic traverse the twisty, two-lane highway just a few feet from each other, creating ample opportunities for head-on collisions if a driver so much as hiccups.
Crackups are weekly occurrences. During a 10-year period, two people died every year on average. Every few years, a collision produces multiple fatalities.
No wonder the 6-mile drive between Napa and Solano counties is a white-knuckle experience for many drivers.
Fortunately, that’s about to change.
After years of talk but no action, construction began in early 2012 to widen Jameson Canyon from two to four lanes, with a concrete median to prevent head-ons. The project will cost $130 million, the majority coming from state coffers.
When the last of the work is finished on the Solano County side in 2015, Jameson Canyon will be tamed, creating safer conditions for the 32,000 motorists who use it daily.
Improvements to Jameson Canyon were a long time in coming. The widening project was the county’s top highway priority for a decade, but the funds to build it could not be found.
In 2006, the Napa County Transportation and Planning Agency supported Measure H, a half-cent increase in the local sales tax to pay for Jameson Canyon improvements and a host of local street and road projects.
The measure won majority support, but fell far short of the needed two-thirds majority, with critics saying that county residents should not be in the business of paying for highway improvements. That’s the state’s job, they said.
A year later, Napa County hit the jackpot. The California Transportation Commission awarded state highway bond money to eliminate this regional bottleneck.
Napa never would have received Proposition 1B funds without the support of Solano, Sonoma and Marin counties, said Napa County Supervisor Bill Dodd. “My colleagues saw the value of this east-west connector,” he said.
What Dodd fails to mention is his behind-the-scenes role as chair of the Metropolitan Transportation Commission in putting together a coalition to push for state funding after the local sales tax failed.
“Sometimes you’re in the right place at the right time,” Dodd said.
Motorists will be winding through a construction zone on the Napa County portion of Jameson Canyon through 2013, while the Solano section won’t wrap up until 2015.
When complete, Jameson Canyon will have two lanes in each direction between Highway 29 and Interstate 80, eliminating the rush hour crawl. But the Jameson project is not the ultimate solution for the thousands of commuters who flow into Napa County daily from Solano County.
Caltrans will be working for many years on improvements to the intersection of Jameson Canyon and I-80 so traffic can flow seamlessly onto the interstate, Dodd said.
At the Napa County end, an interchange is planned for the juncture of Jameson Canyon and Highway 29, but Caltrans lacks the money to build it. Traffic on Highway 29 near the Jameson intersection will continue to be anything but fast-flowing at rush hour.
It’s possible that a safer, four-lane Jameson will attract some motorists who are currently detouring through American Canyon on Highway 29 to avoid the threat of a head-on, Dodd said. The county is planning the extension of Devlin Road, which may also siphon some traffic off Highway 29 in the south county, Dodd said.