It’s a famous, near-hairpin turn in Sonoma County, a white knuckle, hard-braking maneuver that takes commitment, focus and maybe a dash of bravery.
No, it’s not Sonoma Raceway. It’s the Gas Club turnoff, one of several hair-raising driveways off Highway 101 south of Petaluma set to close for good in the near future.
The driveway where Kastania Road dumps directly onto Highway 101 is set to shut down permanently as part of Caltrans’s latest round of freeway improvements, a $91.8 million project that will also improve flood protection and sight lines for the roadway as it curves over San Antonio Creek between Sonoma and Marin counties.
Workers are expected to fully close the Kastania driveway as soon as next week, along with a direct connector to San Antonio Road and, later, at the smaller Gunn Drive.
Drivers on those roads will no longer be able to careen across Highway 101 in a pedal-to-the-metal push across as many as four lanes of traffic, instead forced to meander along new parallel routes toward improved interchanges at Kastania and San Antonio. Work to close off northbound-side connections along the stretch is anticipated to go forward later in the project, fully shutting down all driveways in the area, according to information from Caltrans.
The closures will bring new sanity to a stretch of roadway already besieged by traffic woes.
“Frontage roads will improve safety for motorists and residents in the area,” said Allyn Amsk, a regional spokesman for Caltrans.
It is not uncommon for Highway 101 to morph into something of a main street as it passes through the more rural towns of Northern California, with shops and residential driveways often lining the roadway as it meanders through the more remote spans of the North Coast. Yet such features are rare in the Bay Area, a region that has a far greater volume of daily commuter traffic.
Though significant gaps remain, work along Highway 101 between Sonoma and Marin counties over the past decade has transformed much of the roadway into something more akin to the infrastructure seen elsewhere in the Bay Area, with high-occupancy vehicle lanes and a number of improved interchanges.
First built in the 1950s, the two-lane stretch south of Petaluma remains a relic of the region’s more rural past, a time when driving directly across Highway 101 was perhaps a more reasonable — and safe — thing to do.
Despite continued usage of those frontage driveways in recent years, Petaluma Fire Department Battalion Chief Mike Medeiros said they are not known to be a particularly prominent factor in vehicle accidents. The driveways have at times been useful for emergency responders accessing incidents along that stretch of the freeway, though the new Kastania interchange in southern Petaluma also provides adequate access, he said.
Likely the most well-used of those driveways is the Gas Club turnoff. Cars crammed the station during last Thursday’s morning commute, where several drivers described themselves as long-haul commuters who have made the freeway-fronting stop part of their regular routine.
News of Caltrans’ plans to close off direct freeway access to the property came as a surprise to a number of commuters that day, where many praised the station’s location and competitive pricing. Several drivers said they were unsure of whether the cost savings alone would be enough to keep them coming back via the longer out-and-back route.