California Department of Transportation

US 101: Corridor System Management Plan
(Santa Maria to Arroyo Grande)

The US 101 Corridor System Management Plan (CSMP) is a condition of Proposition 1B Corridor Mobility Improvement Account (CMIA) funding for the Santa Maria River Bridges widening project and Union Valley Parkway Interchange project. The CSMP extends across the San Luis Obispo and Santa Barbara county line. The corridor is approximately 22 miles from the Clark Avenue /US 101 interchange (pm 82.18) just south of Santa Maria to the Grand Avenue/US 101 interchange (pm 13.17) in the City of Arroyo Grande. The corridor limits extend beyond the highway to include a comprehensive analysis of areas adjacent to and surrounding the highway as well as consideration of all transportation modes.

The CSMP assesses current performance and identifies congestion conditions along the corridor. Analysis of existing conditions and deficiencies resulted in the development of recommended solutions and strategies to achieve the greatest efficiency and sustainability of the transportation system. CSMP efforts began in March 2010 with the initiation of San Luis Obispo County's US 101 South County Corridor Transportation Study. This study is within the limits of the US 101 CSMP and provided support for the technical analysis of the CSMP.

The CSMP was developed in partnership with representatives of the local and regional transportation planning agencies within the corridor and was accepted as an effort to support the regional transportation planning process by Santa Barbara County Association of Governments (SBCAG) and San Luis Obispo Council of Governments (SLOCOG).  The final document was approved by Caltrans June 2012.


Hana Megsteab (Acting Branch Chief)
(805) 549-3130


Melissa Streder, Associate Transportation Planner
(805) 549-3800

Last updated: February 22, 2017