The Sonoma-Marin Area Rail Transit (SMART) Windsor Extension advances SMART’s mission to reconnect North Bay communities through sustainable, modern passenger rail. Extending 3.2 miles north from Sonoma County Airport Station, the project restores passenger service to downtown Windsor. STV collaborated with SMART to design a multimodal rail corridor that enhances regional mobility, improves access to jobs and education and supports transit-oriented development, while reducing reliance on single-occupancy vehicles.
What challenges did STV overcome?
Designing the Windsor Extension meant adapting a historic freight corridor for contemporary passenger use while coordinating upgrades to bridges, crossings, and drainage systems along the route. The project’s location – adjacent to active communities and established roadways – required STV to minimize disruptions and align infrastructure improvements with local planning goals. The team also addressed site-specific conditions, including stormwater management, accessibility compliance and the integration of pedestrian and bicycle pathways, to meet SMART’s safety and sustainability standards.
What solutions did STV deliver?
STV provided comprehensive design services for the extension, encompassing rail infrastructure, civil and structural engineering, station design, and bridge reconstruction. The firm’s multidisciplinary team developed solutions that balanced technical performance with community context –upgrading multiple bridges, designing new at-grade crossings and incorporating a continuous shared-use path alongside the rail alignment. In Windsor, the station design emphasizes walkability and visual harmony with the town center, featuring accessible platforms, passenger amenities and clear multimodal connections.
How does the Windsor Extension benefit the North Bay?
By extending the SMART service northward, the Windsor Extension expands sustainable transportation options for residents and visitors, while stimulating local economic activity. The new station strengthens downtown Windsor as a transit-oriented destination, connecting homes, schools and businesses with the broader regional rail network. As part of SMART’s long-term plan to reach Cloverdale, this extension represents a major step toward a fully realized North Bay commuter system—one that combines mobility, environmental stewardship, and community-focused design.
Key Stats and Accolades
- Extension length: 3.2 miles from Sonoma County Airport Station to downtown Windsor
- Bridges/crossings reconstructed: Five rail bridges, two pedestrian bridges, one pedestrian underpass, five upgraded at-grade crossings
- Station location: Downtown Windsor, walking proximity to businesses, schools, parks and civic use
- Multimodal pathway: 2.6 miles of pathway designed in parallel with the rail extension
- STV’s system contributions: STV has designed 45 of SMART’s 48 active miles, including 30+ bridges, 90 grade crossing upgrades, station infrastructure and portions of the accompanying bike path system
