US 101/Hearn Avenue Regional Multimodal Interchange

For Updates See Project Schedule Below -

Project Scope

This is a rendering of the project on an aerial image. It shows the project limits from roughly Corby Avenue crossing US 101 to Santa Rosa Avenue, the southbound US 101 off-ramp to where it intersects with Corby Avenue, and the section of Corby Avenue from that intersection to Hearn Avenue. The rendering shows the increased width that will include additional travel lanes, raised median, sidewalks and bikeways, and provides a cross section view of the roadway with these improvements. The rendering also shows how the project will connect to the SMART multi-use path to the west and proposed ADA elements at the intersections within the project limits.The US 101 Hearn Avenue Regional Multi-modal Interchange Project will demolish and reconstruct the Hearn Avenue interchange overcrossing in the same location to increase vertical clearance over US Hwy101, widen the overcrossing to provide two vehicle lanes in each direction, a median, sidewalks, and two Class IV bike lanes extending to Corby and Santa Rosa Avenue. The project will also widen the southbound US 101 off-ramp with turning lanes at its intersection with Corby Avenue, add lanes at the intersections of Hearn Avenue/Corby Avenue and Hearn Avenue/Santa Rosa Avenue, and add pedestrian curb ramps and crosswalks that comply with the American Disability Act and incorporate protected intersection facilities for bike crossings and detection to reduce potential conflicts between bikes and vehicles.

The project is the final phase of the Hearn Avenue and Santa Rosa Avenue Complete Streets Project to provide roadway widening, pedestrian, and bicycle improvements intended to improve mobility in southern Santa Rosa.

Project Purpose

The project will relieve traffic congestion and improve regional traffic operations, including providing multimodal access and connectivity adjacent to the Highway 101 and Hearn Avenue intersection.

Current Conditions:

  • Existing Hearn Avenue overcrossing is one lane in each direction with no shoulders
  • Insufficient capacity for vehicles leads to queuing back onto the mainline southbound US 101 auxiliary lane during peak periods
  • Congestion and lack of shoulders delays emergency response times
  • No sidewalk on the north side and discontinuous sidewalk on the south side
  • No bike facilities on Hearn Ave overcrossing
  • Nonstandard vertical clearance over US 101
  • Non-crashworthy bridge railings

Project Benefits:

  • Improve local traffic circulation and regional traffic operations (resulting in improved first responder access and response time)
  • Improve multimodal access, connectivity, and operations
  • Improves access to essential goods, services and jobs
  • Improves access to recreation
  • Improves access to schools and adult educational and career development
  • Improves access to public transit and transit travel times
  • Improve overall safety of the facility

Project Schedule

May 16, 2024

Right-Turn Lane to Close on Westbound Hearn Avenue Overcrossing

Caltrans will close the right-turn lane from westbound Hearn Avenue to northbound Corby Avenue before the morning commute begins on Wednesday, May 28, 2024.  The turn-lane will be closed for nine months as Caltrans will use the area now occupied by the turn-lane to build the north side of a new, wider overcrossing. 

During the closure, the westbound lane on Hearn Avenue will serve vehicles turning right or left onto Corby and vehicles traveling straight on Hearn Avenue.  Westbound motorists should allot more travel time during the closure, as capacity on Hearn Avenue will be reduced.  A left-turn lane on westbound Hearn to southbound Corby Avenue will remain open. 

Please return to this webpage next week as maps and other update to the project will be published. 


Project Contact

For more information, contact Caltrans Sonoma County Public Information Officer Jeffrey Weiss.