Highway 37 Corridor Study

May 8, 2019:  The SR37 Travel Behavior and Transit Feasibility Study is now available. Download Here

March 2, 2018:  SR37 Transportation and Sea Level Rise Corridor Improvement Plan is now available. Download Here


Read more about the SR-37 Policy Committee

State Route 37 (SR 37) traverses through Sonoma, Marin, and Solano counties in highly sensitive marshland in the northern portions of the San Francisco Bay wetlands. The 21-mile corridor is an important regional connection linking the east and west portions of the North Bay Area by connecting I-80 and SR 101. Portions of SR 37 are highly congested during weekday commute periods but also on the weekends. The corridor is heavily traveled on the weekends by recreational travelers visiting the wine country in both the Napa and Sonoma valleys. Portions of the corridor between SR 121 and Mare Island experience large amounts of delay due to the highway narrowing down from four to two lanes. 

Marin, Napa, Sonoma and Solano counties have been actively participating in a joint analysis conducted by Caltrans and UC Davis Road Ecology Center identifying SR 37 corridor’s vulnerability to sea level rise.  Early conclusions have identified portions of SR 37 that will be completely inundated by 2050, as well as increased flooding events along several sections of the corridor leading up to 2050. The threat of sea-level rise coupled with the growing congestion issues on SR 37 makes it a priority corridor for all four North Bay counties.  Recognizing that something must be done, all four North Bay counties have agreed to partner in planning near and long term solutions for the corridor.  In December 2015, a Memorandum of Understanding (MOU) was signed by all four North Bay County Transportation Authorities “…to develop an expedited funding, financing and project implementation strategy for the reconstruction of SR 37 to withstand rising seas and storm surges while improving mobility and safety along the route”. As a result of the MOU, policy representatives from each of the four North Bay counties agreed to meet regularly forming the SR 37 Policy Committee.  Meetings are held on the third Thursday of every other month at 9:30 AM at a location in one of the four counties.

Further documentation, meeting notices and agendas can be found at the: Sonoma County Transportation Authority.


November 3, 2016 Agenda Packet

September 1, 2016 Agenda Packet

July 7, 2016 Agenda Packet 

July 20, 2018 Agenda Packet

November 8, 2018 Agenda Packet

March 7, 2019 Agenda Packet

December 5, 2019 Agenda Packet

January 16, 2020

June 4, 2020 Agenda Packet

October 1, 2020 Agenda Packet

January 7, 2021 Agenda Packet

March 4, 2021 Agenda Packet

June 3, 2021 Agenda Packet

October 7, 2021 Agenda Packet

January 6, 2022 Agenda Packet

March 3, 2022 Agenda Packet

June 2, 2022 Agenda Packet

September 1, 2022 Agenda Packet

December 1, 2022 Agenda Packet