Busses can fool me thrice

August 30, 2022

Public transit is often framed as necessary philanthropy for cities. It cuts down on cars and pollution at the expense of convenience. If people can more efficiently get to their destination by other means, they will.

This is the wrong way to look at things.

Public transit at its best can be additive for individuals, not just the aggregate good. You don't have to worry about parking, you don't have to worry about traffic, and you know exactly how long it's going to take to get from Place A to Place B. London, Paris, and New York have this figured out - everyone takes the subway, even if they have other options. There is broad support for public transit because it fits into the everyday fabric of city life. But for public transit to really work, it needs trust.

I was waiting for a Muni early in the spring when I first moved to San Francisco. It was a beautiful day; sun was streaming and traffic was lazy. Green routes all across the city according to Google Maps. The bus schedule said to show up at 11:30 so I showed up at 11:23. A steady stream of cars cruised by. Seven minutes tick by - no bus. I double check the clock. One minute turns into five and then twenty. The next bus showed up early and took off immediately. I was on it but if I had gotten there on time for the official schedule, I would have missed it.

I tried again later that week. Same thing, different route. Citymapper said the bus had come and gone yet there certainly was no bus. Like the bus before, one eventually showed up. I wound up with a 25 minute delay and 10 minutes late to my appointment. This wasn't a big deal given my specific appointment but for someone's job interview, potentially career altering.

It left the impression that busses come when they want and adhere to no clear schedule. With something as integral as mobility, doubting schedule breaks public trust in the system. You might give it a few chances but after three you'll relegate public transit to a form of transport that you'll only use when you have no other options or otherwise have time on your hands.

Promptness is the sole and only KPI that matters for public transit. If you want to plan it into your schedule, it needs to be trustworthy. MUNI was on time 57.3% of the time in 2018, which was down from 59.8% of the time in 2016. Being on-time in their report also factors in some fuzziness: -1 minute to +4 minutes of scheduled time. This statistic is abysmal. It's a coin flip that your bus will come on time. And as far as I can tell there's no public tracking on the variance of delays. How often are busses delayed 10 minutes or more? 20 or more? The city's goal is for 85% of busses to come on time but the numbers have remained stagnate for at least the last decade. The 58% average just won't budge.

It feels like there are some easy things that metros (especially the San Francisco one) could do today to increase trust:

  • Every bus should have a GPS beacon with its current location, status, and projected delay. These are available on some routes but not all. Roll them out across the board. Go with the low-fidelity consumer hardware model like SpaceX. Don't use hardened infrastructure that charges an exorbitant markup. Just use an android cellphone with custom software.
  • Have busses been explicitly canceled? Publish cancelation notices online. List the date, bus number and time on one page, versus global announcements that cover multiple lines. More ideally integrate with the most used transit apps across Google Maps, Apple Maps, and Citymapper.
  • Avoid riders fiddling with the bike rack. Keep it always down to optimize the efficiency of boarding or deboarding without the variance of whether riders need to strap their bike.
  • Wait for arrival time. If a bus arrives at a stop before the scheduled arrival time, wait. It's better for a bus to be 5 minutes late than 5 minutes early.

Other actions to increase reliability are more impactful but more complicated. They also typically require public financing to change underlying infrastructure. However, cities need to start with trust. If more people trust the transit system, they'll be more likely to approve upgrades. Without trust, people are going to keep using their cars.