Route 116 Safety Improvements between Frates Road and Stage Gulch Road


Project Limits

Caltrans and its partners have long considered a safety project on Lakeville Highway between Frates Rd and Stage Gulch Road, but funding has been an issue.


Without getting into excessive detail, funding agencies look for specific criteria, including accident rates, increased traffic, etc., before deeming a project appropriate for financing. While that might sound regressive - funding a project only after increased traffic or accidents - consider the competition for funds, as municipalities from San Diego to Eureka compete to fund safety projects, they feel are necessary.  


After the recent collision at Lakeville Highway and Pine View Way, Caltrans Bay Area applied for and received emergency funding (a Director's Order) for significant safety improvements.  


Not all improvements can be made under the Directors Order, as money is limited. Some upgrades require more money and time, and larger projects will be subject to the project development process, in which they progress through a series of phases - scoping, environmental, design, etc. - before construction can start.  


As such, Caltrans and its partnering agencies have divided this larger project into three components: Improvements Made to Date, Phase I Improvements, and Phase II Improvements.




Improvements Made to Date

Closed Roads

  • A Safety Working Group was established by Caltrans in collaboration with the City of Petaluma, Sonoma County Transportation Authority, CHP, and other local agencies in December 2023 to assess safety issues along Lakeville Hwy (SR 116).
  • Caltrans completed a Rumble Strip project, installing centerline and shoulder rumble strips from Frates Road to Pine View Way.
  • The City of Petaluma closed outbound access to Lakeville Highway from Pine View Way and South McDowell Extension to Lakeville Highway.
  • Caltrans adjusted the signal timing at the Frates Road and S. McDowell Boulevard intersections to accommodate rerouted traffic from the outbound closures on the S. McDowell Boulevard Extension and Pine View Way. Caltrans will continue to monitor this corridor to assess traffic impacts.


Phase I ImprovementsMerge Ahead or Lane Drop

Traffic engineers have noticed a lot of aggressive driving on eastbound Lakeville Highway. Anticipating an upcoming lane drop, slower-moving traffic, often large trucks, migrate into the left lane (the through-lane), where merging may be more straightforward. Unwilling to be stuck behind slower vehicles, impatient drivers use the right lane (the merging lane) to pass, speeding ahead as they try to beat the slower traffic to the lane merge. 


Caltrans has a Safety Improvement Project planned for the Pine View Way intersection. But that will be part of the Phase II Project. To help provide interim safety countermeasures in the meantime, however, Caltrans recommends dramatically reducing the length of the merge lane to reduce the opportunity to speed. 


To do this, Caltrans has converted the two eastbound Lakeville highway lanes to a single lane starting just past Frates Road.


Merge Lane Closed Off Merge Lane Closed Off with Delineators 

Caltrans has restriped the right lane with chevrons, vertical delineators and channelizers. This improvement includes traffic safety signing, a pair of speed feedback signs, and striping for right turn pockets at the S. McDowell Blvd Extension and Pine View Way.

Phase II Improvements

Long-term improvements, still in the project development phase, will involve an intersection improvement project at the Lakeville Highway and Pine View Way intersection. Completion of this phase is estimated to take four years.


Additional improvements

Safety Project at Stage Gulch Road intersection:

In the Summer of 2025, Caltrans is scheduled to begin construction of a roundabout at the intersection of Stage Gulch Road and Lakeville Highway south of Petaluma in Sonoma County. The roundabout will replace an existing three-legged intersection where Stage Gulch Road and Lakeville Highway converge in the semi-rural area of Lakeville south of Petaluma. Construction should be completed by spring 2026 

Caltrans - Route 116 Lakeville Hwy and Stage Gulch Road Intersection


A CAPM project from 101 Hwy to Roche Road:

This project would rehabilitate pavement, upgrade curb ramps, and add bike lanes on State Route 116 from PM 35.04 to PM 39.3. The construction of this project is scheduled to begin by Fall 2028.