USA: The Mid-Coast Extension of San Diego’s light rail network was opened for revenue service on November 21, when the San Diego Association of Governments hosted celebrations at the University of California San Diego Central Campus in La Jolla.


The 17·7 km extension adds a further nine stops to the network, running north from a junction with the Green Line at Old Town. After bridging the San Diego River, it parallels the existing railway used by Amtrak and Coaster commuter rail services and the San Diego Freeway as far as the University campus before turning east to reach UTC Transit Center.

The route is operated by San Diego MTS as an extension of its north-south Blue Line from San Ysidro, which previously terminated in Downtown San Diego. Free travel was provided on the opening day, when services began with the 05.03 departure from UTC Transit Center.

‘This is a historic day for the San Diego region as we commemorate one of the largest infrastructure projects in our history’, said SANDAG Chair and Encinitas Mayor Catherine Blakespear. San Diego Mayor Todd Gloria added that the project ‘will give San Diegans more clean transportation options that help us reach our bold climate goals while creating good jobs’.


The extension is expected to improve access to growing employment, education, and expanding residential areas, as well as relieving congested roads. The population in the corridor is predicted to increase by 19% by 2030, while employment is forecast to rise by 12%. Ridership is expected to be around 20 000 passengers per day.


Federal funding

Budgeted at $2·2bn, the line was designated as a priority project by the San Diego Association of Governments, which in 2014 selected the Mid Coast Transit Constructors joint venture of Stacy & Witbeck, Skanska USA and Herzog Contracting Corp as main contractor. The Federal Transit Administration signed a Full Funding Grant Agreement in September 2016 covering 50% of the cost, with the remainder coming from TransNet, the region’s half-cent sales tax for transport improvements.


Construction began in autumn 2016, and SANDAG handed the route over to MTS for test running to start in July 2021. According to the agency, the final cost was about $13m below budget.

In November 2016 MTS ordered 45 S70 low-floor LRVs from Siemens Mobility to operate the Mid-Coast Extension and increase capacity on the rest of the network. These were assembled at the Siemens plant in Sacramento, with the last being delivered in October 2020. A further 25 vehicles were ordered in 2019.