Gold Line Foothill Extension: 2026 Construction Update

Project Profile: Metro A Line (Foothill Gold Line) Extension Phase 2B

The Metro A Line Foothill Extension Phase 2B is a critical light rail transit project extending service from Glendora to Montclair, California. This profile details the engineering specifications, construction phasing, and operational parameters of this complex undertaking, which integrates new infrastructure within an active freight and commuter rail corridor. The project is designed to significantly enhance regional mobility and alleviate traffic congestion in the San Gabriel Valley.

Technical Specifications

The project’s primary engineering challenge is the construction of a new double-track light rail system within a constrained 100-foot-wide right-of-way shared with BNSF (formerly ATSF) freight and Metrolink commuter services. To deconflict operations, the project utilizes a phased approach: first, relocating and rebuilding the existing freight and Metrolink tracks to one side of the corridor, and second, constructing the dedicated light rail tracks and systems. The scope includes the reconstruction or new construction of 23 bridges and improvements at 28 grade crossings to ensure operational safety and efficiency across all three rail services. The light rail system is powered by a standard overhead catenary system fed by 11 new traction power substations.

The rolling stock consists of modern Light Rail Vehicles (LRVs) operating in multi-car configurations with a capacity of up to 200 passengers per train. The extension will feature six new stations at Glendora, San Dimas, La Verne, Pomona, Claremont, and Montclair, complete with parking facilities and amenities designed for seamless passenger integration. Communications and safety systems, including a state-of-the-art train control system, are being implemented to manage the high frequency of service, which is projected to exceed 200 daily train trips upon full operational commencement.

Key Takeaways

• Complex Corridor Integration: This project serves as a key case study in integrating new light rail infrastructure into a busy, pre-existing freight and commuter rail corridor without disrupting ongoing services, a common challenge in urban rail expansion.
• Significant Economic Stimulus: With a projected economic output of $2.6 billion and the creation of over 7,000 jobs, the extension is a major driver of regional economic activity and provides long-term value through improved transit access.
• Congestion Mitigation: By providing a reliable, high-capacity transit alternative, the A Line Extension is forecast to significantly reduce vehicular traffic and associated emissions along the heavily congested I-210 freeway corridor.

Frequently Asked Questions (FAQ)

When will the Gold Line extension to Montclair open?
The first segment of the extension from Glendora to Pomona is projected to open for passenger service in 2026. The final segment from Pomona to Montclair is pending additional funding, and its opening date has not yet been determined.

Who is building the A Line (Gold Line) Foothill Extension?
The project is being planned, designed, and built by the Metro Gold Line Foothill Extension Construction Authority, an independent transportation planning and construction agency. It will be operated by the Los Angeles County Metropolitan Transportation Authority (Metro) upon completion.