The 101/23 Interchange Improvement Project in Thousand Oaks Starting Soon

The City of Thousand Oaks, Caltrans and Ventura County Transportation Commission are initiating the US Highway 101/State Route 23 Interchange Improvement Project soon!

The 101/23 interchange is one of the most congested freeway segments in Ventura County during peak travel periods. The project will widen the freeway and some of the existing connectors and ramps. Specifically, the project will:

  • Add a lane to the southbound 23 to northbound 101 connector and southbound 23 to southbound 101 connector.
  • Add a lane to the northbound and southbound US 101 freeway at various locations between the Los Angeles/Ventura County line and Moorpark Road.
  • Widen three bridges (northbound side only) at Hampshire Road, Conejo School Road and Moorpark Road. Construct soundwalls between Hampshire Road and Conejo School Road on  northbound side of 101 and between Manzanita Lane and Hampshire Road on the southbound side of the 101 freeway.
  • Realign Moorpark Road northbound onramp and offramp. The 101 northbound onramp will be reconstructed to include an additional lane. The Moorpark Road undercrossing will be widened.
  • The southbound Westlake Blvd onramp will be reconstructed to add an additional lane. The 101 will be restriped in the vicinity of Westlake Blvd to provide five mixed flow lanes.

The project is expected to be completed in early 2016 and is anticipated to relieve traffic issues at the interchange, improve traffic safety and operations at the interchange, improve local traffic flow and commutes and enhance air quality.

Projected closures of US 101/SR-23 connectors, surface streets and on/offramps will take place intermittently throughout the two-year project. Closures will take place during off-peak hours whenever possible.

To learn more about specific closures and project updates, visit the project website on the City of Thousand Oaks website at You can also sign up for email updates at that link.


Residents are invited to attend a community meeting to learn about the upcoming improvements, general construction schedule and closures. Caltrans and City of Thousand Oaks staff as well as the project designer will be on hand to answer questions on Wednesday, February 5th from 6-8PM at the Thousand Oaks Civic Arts Plaza, Founders Room, 2100 Thousand Oaks Boulevard, Thousand Oaks.

Highlights of 101/23 Interchange Project Improvements (Courtesy of Caltrans). Click image for link to larger image on Caltrans website.Click image for larger image on Caltrans website.