San Francisco’s Central Subway
San Francisco is a famously different and defiant city. It was the only major city in the United States to escape much of the urban decay of the 1960’s and 1970’s. The median income in San Francisco is higher than most of the city’s inner suburbs and luxury condominiums in the South of Market (SOMA) neighborhood are being built at breakneck pace. Although growth continues, transit investment in San Francisco has been minimal. BART was the only large transit project completed in San Francisco before the 2000 opening of light rail service along the Embarcadero. The pace of transit expansion has increased markedly since that small extension. Two current multi-billion dollar projects, the Central Subway and Transbay Transit Center are the largest investments in San Francisco’s transit infrastructure since BART. While both of these projects have many merits and flaws, the Central Subway is already under construction so I will begin with a discussion of this light rail extension.
The T-Third Street Light Rail Project, the second phase of which is the Central Subway, was the first entirely new light rail line in San Francisco since the 1980’s. The first phase of the line connected the Visitacion Valley and Bayview/Hunters Point neighborhoods, both highly transit dependent, to the Muni Metro system at 4th and King streets in SOMA. The Central Subway, now under construction, will connect 4th and King streets with Chinatown and the Market Street Subway, completing a parallel route to the 8x Bayshore Express Bus, which serves over 30,000 riders daily. The first phase of the project, the surface level light rail down Third Street to Sunnydale has many flaws, but only cost 780 million dollars, chump change in the rail transit world. The Central Subway, on the other hand, is budgeted at over 1.2 billion dollars for less than two miles of track and three subway stations.
Such a short, expensive transit line should be designed well, cut no corners on construction or capacity, and have an appropriate amount of properly located stations, right? Unfortunately, the Central Subway fails at all three of these simple objectives. Design-wise, the Central Subway botches the transfer to the Market Street Subway’s Powell Street station. The Powell station is already very deep, the BART level being almost 100 feet underground. To pass under the BART platform, the Central Subway’s Market Street/Union Square station will be 140 feet deep and located over 1000 feet away from the existing platforms. A long walk through an underground passageway will be necessary to transfer between the lines. To make matters worse, the majority of riders will be transfer riders and riders who took the 30 Stockton bus in the past. Even with the Central Subway, the 8x bus that parallels the completed T-Third Muni Metro line will go from Chinatown to Visitacion Valley in less than 30 minutes, compared to over 45 minutes by light rail, so through riders are unlikely. The demographic of riders means that this transfer must be as seamless as possible.
An alternative to the current plan would be a slightly different alignment, bringing the tunnels up to an area not directly under the Powell Station. In this case, the platforms for the T-Third could be build directly below the BART tracks and have a much shorter walk and 30 foot elevation change to get to BART or other Muni lines.
Capacity constraints are another serious issue with the current design of the Central Subway. The vehicles Muni plans to run on the line are 75′ LRV’s, identical to those already in service. Technical constraints with these Breda-manufactured cars prevent train consists from running with more than two cars. This is unacceptable for a high-capacity rapid transit project. Muni must purchase new vehicles that can run in 3-4 car consists if they want to fulfill the demand for travel on this corridor. Also, because Muni’s current fleet can only run 2 car trains, platforms for the Central Subway are only going to be 150 feet long. Paying the millions of dollars for the tunnels and building tiny 150 foot stations would be a disaster. The cost of building longer platforms now will be much lower than attempting to lengthen platforms later when demand outstrips capacity, as it inevitably will.
The final critical omission in the plan for the Central Subway is an underground station in North Beach. The tunnel boring machine will be removed at a pit in North Beach along Columbus Avenue. Why not build a station while you have a large underground hole with light rail tracks in it? This fourth station would greatly increase ridership and greatly enhance the utility of the rest of the line by providing a connection to a dense, vibrant neighborhood. Finding the funds for this station now instead of building it later would save a large amount of money.
The Central Subway will be a good addition to San Francisco’s transit system, but its flaws will hamper its utility. If Muni manages to correct these flaws by providing a better transfer at Market Street, greatly increasing capacity and building a North Beach Station, the Central Subway will be a truly great transit project.