Measure M Projects
Highway 101 Project #4 – Marin-Sonoma Narrows (MSN)
From State Route 37 in Novato (Marin County) to Old Redwood Highway in Petaluma (Sonoma County)
Project Delivery Strategy:
The Environmental Assessment/Environmental Impact Report covers improvements over a 17 mile long corridor through both Marin and Sonoma Counties. Due to funding constraints, Caltrans, SCTA, and the Transportation Authority of Marin (TAM) have implemented a phased delivery strategy. To accelerate improvements at the East Washington Interchange in Petaluma (Phase C1), a separate Initial Study with Mitigated Negative Declaration was completed in March 2008. The Environmental Assessment/Environmental Impact Report (EA/EIR) for the remainder of the phases was completed in July 2009.
In 2008, SCTA, Caltrans and the Transportation Authority of Marin (TAM) began a strategy of phasing the MSN project into a series of fundable contracts, in order to leverage available fund sources. Phase 1 initially consisted of Contracts A1, B1, B2, B3, and L1. The Phase 1 strategy was to upgrade the “Narrows” section (Segment B) of the project to freeway standards, by constructing frontage roads, constructing a Class I and II bike/pedestrian path, relocating utilities ,and eliminating uncontrolled access to the facility. The frontage roads will be served by two new interchanges at Redwood Landfill (Contract B1) in Marin County and Petaluma Boulevard South (Contract B2) in Sonoma County. Contract B3 will correct the horizontal alignment of Highway 101 at the County Line, and will complete the frontage roads and the bicycle path. Phase 1 also provided congestion relief in Marin county by constructing HOV lanes in Novato (Segment A).
By continuing the strategy of getting projects construction ready, additional contracts and scope have leveraged additional funds and new work has been added to the Phase 1 projects. The replacement of the Petaluma River Bridge was added to Contract B2 and Contract C3 replaces the Highway 101Lakeville Highway Bridges. Contracts A2 and A3 in Marin County were also added to further extend HOV lanes. Finally, the County Bridge on San Antonio Road was funded by the Federal Highway Bridge Rehabilitation and Replacement (HBRR) program and added to Phase 1. SCTA and TAM are splitting the L1 Landscaping Contract. The L1 contract in Sonoma, which would plant trees along the limits of the B2/C3 project is in plant establishment. The L1 soundwall and landscape project in Marin is in plant establishment. In all, $27.9 Million in Measure M funds were used to leverage $419 Million in other fund sources for Phase 1 MSN projects.
SCTA estimates that all carpool lane projects in Sonoma are fully funded due to the May 2018 programming of SB-1 Solutions for Congested Corridors Program (SCCP) funds by the California Transportation Commission. In Sonoma, Phase 2 projects include Contracts C2 (HOV widening through Petaluma) and the Sonoma Median Widening (B2 Phase 2) project (HOV widening from the County line to Petaluma Boulevard South). The 2014 Strategic Plan used Measure M funds to fully fund the design and right of way phases of the C2 Contract. Federal Funds were used to design the Sonoma Median Widening project which is now under construction.
South of the county line, SCTA estimates that another $120 Million is needed to complete the HOV lane network (A4 and B1 Phase 2). Although Measure M funds are not eligible for projects in Marin, SCTA understands the importance of these projects to Sonoma County and continues to advocate for funding the remaining contracts needed to create a continuous HOV lane network from Sausalito to Windsor. An estimated $8 Million is needed to completely landscape the corridor. Likely fund sources to complete the work in Marin and landscape corridor include SB-1, Regional Measure 3 and a Marin County Sales Tax Measure that was approved in November 2018.
All A Contract are in Marin County
A1 Contract – Highway 101 High Occupancy Vehicle (HOV) Lanes (northbound – Route 37 to Atherton Avenue & Southbound Route 37 to Rowland Boulevard in Novato) (Phase 1)
Contract A1 Schedule / Status – This project started construction in July 2011 and was completed in December 2012.
A2 Rowland Boulevard to Franklin Avenue Overhead in Novato) (Phase 1)
Contract A2 Schedule / Status – This project started construction in November 2012 and was completed in December 2013.
A3 Contract– Highway 101 High Occupancy Vehicle (HOV) Lane (northbound – Atherton Avenue to 1.6 Miles North of the Novato Overhead) (Phase 1)
Contract A3 Schedule / Status – This project started construction in September 2012 and was completed by November 2014.
B1 Contract – Convert Redwood Landfill Interchange to full, standard interchange with Frontage Roads and Class I and II bikepath (Phase 1)
Contract B1 Schedule / Status – This project started construction in October 2012 and was completed by April 2016.
Contract B2 – New Petaluma River Bridge & New Petaluma Boulevard South Overcrossing/Interchange with Frontage Roads (Phase 1)
Contract B2 Schedule / Status – This project started construction in November 2012 and was completed in November 2017.
B3 Contract – San Antonio Creek Re-alignment (Phase 1)
Contract B3 Schedule / Status – This project started construction in March 2016 and expected to be completed in 2019.
B6 County Bridge Contract – San Antonio Creek County Bridge (Phase 1)
Contract B3 Schedule / Status – This project is fully funded and designed, but the schedule is unclear due to Environmental status.
B2 Sonoma Segment B Median Widening Contract (Phase 2)
Project Schedule / Status – This project started construction in April 2018 and is expected to be completed in late 2019.
B7 and B8 Marin Segment B Median Widening Contract (Phase 2)
Marin Segment B Median Widening Schedule / Status – This project has partial funding at this time. Caltrans and TAM are seeking funding opportunities. B7 is the highway construction and B8 is the right-of-way work.
C1 Contract – East Washington Interchange (Phase 1)
Contract C1 Schedule / Status – This project started construction in November 2011 and was substantially completed in June 2014.
C2 Contract – Petaluma Area HOV Lanes (Phase 1)
Contract C2 Schedule / Status – Design and Right of Way will be complete by the end of 2018. Construction is scheduled to start in the fall of 2019 and open the final HOV lanes in Sonoma County on Highway 101 by the end of 2022.
C3 Contract – Hwy 116(E) Separation Structures (Phase 1)
Contract C3 Schedule / Status – This project started construction in November 2012 and is expected to be completed by June 2015.
L1 Contract – Sonoma – Landscaping (Phase 1)
Contract L1 Sonoma – Schedule / Status –This project is fully funded and scheduled to start construction in 2017 and be completed by 2021..
L1 Contract – Marin – Sound Wall & Landscaping (Phase 1)
Contract L1 Marin – Schedule / Status – This project started construction in February 2016 and is expected to be completed by December 2019.
L2 Contract – Landscaping (Phase 2)
Contract L2 Schedule / Status – This project has no funding at this time. SCTA, Caltrans and TAM are seeking funding opportunities.
Underlined text indicates completed work.
Funding (in thousands):
* Other includes Federal, State Bond (TCIF, CMIA & SLPP), STIP (RTIP & ITIP), TCRP, SB-1 (SCCP & LPP) and City of Petaluma funding.