URBAN rail is part of the DNA of San Francisco, and the cable cars which glide effortlessly up and down impossibly steep streets are intrinsic to the city’s unique character, carrying millions of tourists each year. San Francisco is also one of the few cities in the United States that never gave up on trams and today’s network, which is still operated by San Francisco Municipal Railway (Muni), blends traditional street running with underground sections in central San Francisco, with a collection of lovingly-maintained vintage trams operating in regular service on selected routes.

SFLightrailMuni is the United States’ eighth-largest transit agency, and the largest public transport operator in the San Francisco Bay Area on a ridership basis, accounting for nearly half of the region’s daily transit trips. Muni carries around 700,000 passengers per day including 164,000 on the 115km Muni Metro light rail network.

Many of the challenges facing the network today stem from its complex history. In the late 19th and early 20th century San Francisco built an extensive tram network serving much of the city. With the construction of the Bay Area Rapid Transit (Bart) metro system in the 1960s and 1970s, a sub-surface light rail line - the Muni Subway - was built beneath Market Street and above the Bart tunnel. This transformed the Muni into a hybrid system with all five-lines feeding into the core underground section, but this mixed lineage means the network’s aged periphery limits the potential of the much younger core.

Muni Metro has the dubious distinction of being one of the slowest transit networks in the United States, and the system is under increasing pressure to deliver more capacity, reduced journey times, and improved reliability. According to SFMTA’s Draft Rail Capacity Strategy, which was published last year, capacity on the Muni Metro Subway is severely limited by inconsistent platform lengths, unreliable surface operations, congestion at the tunnel portals, and operational constraints at terminus stations. This means that the Subway is operating at just 59% of design capacity at peak times.

Furthermore, population growth continues to pile more pressure onto the system. By 2040, the number of households in San Francisco is forecast to grow by almost 30%, while the number of jobs will increase by 35%. Most of this population and employment growth will be concentrated in areas on the existing light rail network, and ridership is therefore expected to continue rising steadily, increasing 80% by 2040.

Several major capital investment projects are underway which will help to build more capacity into the system and the city is working to lay the foundations for longer-term enhancements. “Transit is central to the policy objectives of the city and the future vision is built around transit expansion,” explains Mr John Haley, director of transit (Muni) for San Francisco Municipal Transportation Agency. “One of the biggest challenges we face is that we’re delivering five or six once-in-a-generation capital projects simultaneously. Fortunately, we have had tremendous support across the board to help us do this.”

In September 2014 the San Francisco Board of Supervisors approved a 15-year contract with Siemens for the procurement of up to 260 new S200 SF LRVs, which will expand the LRV fleet by more than 70%. The base contract for 175 vehicles is worth $US 648m and comprises 151 vehicles to replace the Breda LRV2 and LRV3 trams, which entered service from 1996 onwards, together with 24 vehicles to expand the fleet in readiness for the opening of the Central Subway. Assembly is taking place at Siemens’ plant in Sacramento.

SFMTA exercised a $US 210m option for 40 additional vehicles in January 2015, leaving one remaining option for 45 vehicles. These two options will enable Muni to accommodate projected ridership growth and network expansion up to 2040. SFMTA says the price offered by Siemens was 20% lower than the projected cost of the order.

The S200 SFs will be introduced into passenger service this summer and Muni expects to receive 16 vehicles by the end of this year. The fleet will grow to 41 vehicles in 2018 and 64 vehicles by the end of 2019. Withdrawal of the Breda LRVs will not begin until the early 2020s and the delivery of the first 64 Siemens vehicles will enable Muni to address a chronic shortfall in fleet capacity.

“A lot of lessons were learnt from the previous procurement and we wanted to avoid making the same mistakes,” Haley says. “We didn’t buy enough cars, because we only thought about demand at that point in time. Overcrowding is one of our biggest problems, so we’re adding substantially to our fleet. San Francisco’s economy depends on public transit working better - that means expanding and being more reliable.”

Indeed, reliability is one of the key factors driving the fleet renewal programme. On a typical day in 2013, only 114 of the 151 Breda vehicles were available for service, and while reliability has improved in recent years, the fleet averages just 9000km between failures, with door and step faults a major culprit. The tender for the new LRVs specified a minimum of 40,000km between failures - Siemens anticipates it can achieve up to 95,000km between failures with the S200 SF. Simpler maintenance with digital diagnostics and energy-saving features such as LED lighting and a load-dependent HVAC system are also expected to bring down fleet operating costs.

The new LRVs feature longitudinal seating to optimise capacity and a recent pilot showed that the capacity of the Breda vehicles could also be increased by up to 10% with a revised seating layout. However, while the Breda vehicles can only operate singly or in pairs, the Siemens LRVs will be capable of operating in three or four-car formations.

A decade after the last major expansion of the light rail network, the next addition to Muni metro is moving towards completion. The 2.7km second phase of the Central Subway will provide a direct rail connection from the Bayshore and Mission Bay areas to South of Market (SoMa) and the city centre, avoiding the congested 4th and Stockton streets. The extension of the T Third Street Line begins at the Caltrain station at 4th and King streets and includes one surface station at 4th and Brannan Street and underground stations at Yerba Buena/Moscone Center, Union Square/Market Street, and Chinatown.

Construction began in February 2010, and by the end of December 2016 the $US 1.58bn project was 64.4% complete, with opening scheduled for September 2019. Average weekday ridership is forecast to reach 43,521 passengers by 2030.

Looking further ahead, SFMTA’s Draft Rail Capacity Strategy divides priorities for capital improvements into three categories:

  • system-wide investments providing overall network benefits
  • location-specific near-term investments that can be delivered in a five-year timescale, and
  • long-term corridor investments to expand the network

System-wide investments could improve the flexibility of the network and boost capacity and reliability. Potential measures might include electrification and automation of switches and crossovers; installation of additional switches and crossovers to provide greater operational flexibility and resilience; extending stabling sidings for longer trains; delineating transit-only lanes to reduce conflicts with cars; extend platforms for three or four-car trains; and traffic signal priority at road intersections.

Location-specific near-term investments include the construction of turnback tracks, improvements to train control systems, and targeted measures to reduce conflicts with road traffic.

Long-term corridor investments are intended to accommodate population and employment growth with new lines and capacity enhancements to alleviate congestion points. A key priority in this category is a project to extend the Muni Metro Subway to replace the surface section of the M-Line between West Portal station and Parkmerced.

The Muni Subway Expansion Project would include the construction of four sub-surface stations built for four-car trains, creating a high-capacity underground spine through the heart of San Francisco and unlocking latent capacity in the existing Subway. Moving the M-Line underground would also enable a redesign of the heavily-congested 19th Avenue, making the corridor safer for pedestrians, cyclists and transit users. Journey times would also be substantially reduced - according to the 19th Avenue Transit Study, peak M-Line services average only 14-15km/h on this section, primarily due to stops at road intersections.

Preliminary engineering including environmental assessments could begin next year but construction is unlikely to start before the mid-2020s and could take up to 10 years to complete. With an estimated pricetag of $US 2-3bn, state and federal support will be essential if the project is to reach fruition.

Several other Tier 1 enhancements are included in the long-term corridor investments category for implementation after 2025. These include a 4.8km east-west light rail line along Geneva Avenue, which would connect the T-Line on 3rd Street with Balboa Park Bart station; a 10km light rail line along Geary Street and Geary Boulevard serving the area north of Golden Gate Park; and a 1.6km extension of the Central Subway to Fisherman’s Wharf.

With long-range aspirations for expansion and achievable aims to boost capacity and reliability in the shorter-term the Fog City has a clear view of the role transit should play in its future. But at a time of considerable uncertainty overthe future of transit funding in the United States, the challenge will be to convince policymakers at state and federal levels to put funding behind that vision.