Visualizing LRT frequency

There’s a lot of ways to visualize frequency; I’m hoping this is relatively intuitive. Here is the service offered by the light rail networks in Canada and the US. The grid represents a station at the edge of the downtown during the 7 to 8 AM weekday time period; each cell is a minute, and if it has a colour and letter then that’s the train that arrives in that minute.

The two rows for a city represent the two directions; some cities with more complex situations have four rows — in Portland and Houston, the trains run in two different directions, and in Denver, the trains go to two different stations in the downtown area.

A complicated figure showing transit schedules in a grid
Click here to download as PDF

What’s Interesting Here

One thing to note is that rail service doesn’t mean rail service; you can have a 15 minute wait between trains, or a 5 minute wait. Almost all of the services rise to the level of 15 minute “frequent” service, but only a quarter are in the 10 minute headway range that I think of as true frequent service — remember this is rush hour!

While I hate to be a local booster — seriously, look at Calgary. 26 trains per hour in a single direction. This is on 7th Avenue, which runs at street level, mixed with other transit vehicles and crossing roads at lights. This is a frequency even subway systems have a hard time matching. The next busiest stations are Union Station in Denver and 12th and Imperial in San Diego and both are multi-platform stations. Dallas is the next busiest simple two-track configuration, with 70% of the trains Calgary has, and they’re working on building a downtown tunnel to relieve congestion.

Methodology

Not much to say for methodology; it was just a matter of looking up the schedules on 18 different websites. All schedules are current as of Jan 5/2019 (Denver is as of the Jan 13/2019 service update).

The chart is sorted by increasing frequency, with ties broken by the fewest number of services — Seattle, Sacramento and St. Louis all have 10 trains per hour but Seattle has all that service on a single line, where Sacramento spreads it out over three different services.

I’ve only included light rail focused cities; I’ve left out streetcar and commuter rail service (Denver is an interesting hybrid, and I’ve included the A and B there), and I’ve left out cities where there is also a major heavy rail component — the light rail service in Boston or San Francisco are only a portion of the transit picture.

2 thoughts on “Visualizing LRT frequency

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