Why do we need modern train control?
We will modernize Muni Metro to meet San Francisco’s transit needs well into the future with a new, cutting-edge train control system.
The Train Control Upgrade Project would replace the Automatic Train Control System with a Communications-Based Train Control system. Unlike the existing Automatic Train Control System, newer Communications-Based Train Control technology uses Wi-Fi or cellular connections to precisely track and continually communicate with every light rail vehicle in service and keeps software up to date regularly.
Communications-Based Train Control can manage train movements throughout Muni Metro’s entire 74-mile light rail network, both in the subway and above ground. In the subway, Communications-Based Train Control will work like the existing Automatic Train Control System and use automatic headway management to adjust the speed and dwell time of trains. On the surface, Communications-Based Train Control will communicate adjustments to Muni Metro operators who will remain in control of the train.
While GPS is currently used to track Metro trains running on the street, Communications-Based Train Control telecommunications technology is more accurate and more directly accessible to staff in our Transit Management Center (TMC) – Muni’s “air traffic control tower.”
Communications-Based Train Control would also allow Muni Metro trains to take advantage of transit priority signals, improving Metro travel times and reliability. Currently, a separate Vehicle Tagging System (VETAG) detects trains above ground and communicates to the nearby traffic signal to request priority for the train to pass while holding other traffic with a red light. However, this technology is also outdated and ineffective.
These improvements would give operators and TMC staff greater visibility into the movements and operations of Muni Metro trains, resulting in more effective train management and better service for the entire Muni Metro system.
Service and capacity benefits of Communications-Based Train Control
- More consistent travel times and headways. This means customers will experience faster trips and less time waiting, and trains will be able to serve more runs. Watch this video about the SFMTA’s headway management.
- Less bunching and fewer gaps and delays both in the subway and on surface rail. With the current system it can be difficult to switch trains back in the event of delays and prevent vehicles from bunching up.
- Better communication with traffic signals for priority right-of-way.
- Fewer delays entering and exiting subway portals. Currently, trains have to connect to the train control system at the subway portal before entering the subway, which causes train delays. If the connection fails – which is common – the train has to move slower and other trains are held back for safety, causing further Metro delays. With Communications-Based Train Control trains will be connected to the system at all times.
- The ability to expand the capacity of the Muni Metro system with more trains and longer trains. The current system can only handle 2-car trains.
Reliability and maintenance benefits of Communications-Based Train Control
- Eliminate major subway delays and improve reliability by replacing outdated Automatic Train Control System equipment. The old equipment needs to be replaced as soon as possible to keep Muni Metro running.
- Modern technology that is easier to keep up to date with the latest components and software. While replacing old equipment, we will also upgrade to advanced, cutting-edge technology.
- Provide a train control system that supports Muni Metro service at all times. Since the current system is only available in the subway, is very fragile and doesn’t function during off-hours when trains aren’t running, it provides limited benefits. The new system will resolve these issues.
Safety benefits of the Communications-Based Train Control
- Automatic train separation. This means the system knows where all trains are at all times and send guidance to operators to keep trains safely and appropriately spaced.
- Maintain the high standards of safety currently provided in the subway and extend automatic safety protections to surface operations. The current system isn’t available along the surface, so operators have to switch trains into manual mode. The new system will act like the driver assist in new cars to help prevent collisions.
Environmental benefits
For almost 85 years Muni has continuously operated a network of vehicles, including light rail vehicles, that run on 100% greenhouse gas-free Hetch Hetchy hydroelectric power. Our light rail vehicle fleet played a key role in reaching the San Francisco Climate Action Strategy goals in 2017. Upgrading the Muni Metro train control system from Automatic Train Control System to Communications-Based Train Control will help the City meet future environmental goals by allowing the SFMTA to expand sustainable light rail transit for a growing ridership on the greenest transportation system in North America.
TCUP is in line with the City’s voter-approved Transit-First Policy established in 1973. The policy prioritizes public transit, bicycling, and walking on SF Streets as an economically and environmentally preferable alternative to transportation by individual automobiles.
By providing safe, reliable, rapid, and environmentally sustainable transit service, this project will support our city’s economic and population growth while reducing greenhouse gas emissions and resource consumption.