From mindgutter on flickr

(Post title with apologies to Pink Floyd)

Matt Johnson, over at Track Twenty-Nine, noted that with MARTA’s official conversion over to a color-based naming system for their rail system, more than half of America’s rapid transit systems (including Metro) use a color-based system.

Starting in 1965, Boston started referring to lines by color. When Washington’s system opened in 1976, line colors indicated the route of trains. Cleveland renamed their lines to colors two years later, in 1978. When Los Angeles’ rail system started opening, lines were referred to by colors – the first heavy rail line opened in 1993, the same year that Chicago started calling trains Red, Orange, and so on. Baltimore renamed transit lines after colors around 2002. Finally, just last month, Atlanta added their Red, Yellow, Green, and Blue lines to America’s transit repertoire.

There are still 6 systems that don’t use colors to identify lines by names. However, four do differentiate lines using different colors on a map: BART, NYC Subway, PATH, and SEPTA. Miami and PATCO each only operate one heavy rail line, so color is not an issue.

In any transit system, the diagrammatic understanding of the system (often represented by the system map) is a vital element in the user’s understanding of where they are.   Colors offer an intuitive means of understanding this – as evidenced by the numerous systems using color identifiers for their maps, even if not in their overall nomenclature systems.

There are a couple of shortcomings in using color as the main identifier of lines and services, however.  One is the limited potential for expansion – Chicago has the most lines of any system using colors (8 – Red, Blue, Yellow, Orange, Green, Pink, Brown, Purple), and there aren’t a whole lot of extra options for system expansion.  Silver?  Gold?  But would that be too similar to Yellow?

That leads to the other limitation – differentiation between the lines depends solely on color, and when those differences are not evident enough (i.e. differentiating Yellow from Gold, or for a person who is colorblind), you need some sort of alternative.  Metro accomplishes this with the use of words on the trains – spelling out the color on the front LEDs, as well as the destination on the side LEDs and a two-letter color abbreviation on the PIDs.

It’s also worth noting that many airports used to have color-based naming systems, but have switched to letters and numbers for their terminals and concourses.  Growing up in Minneapolis, MSP Airport used to name their concourses with colors, but switched to letters.  The letter/number provides an easier identifier to the colorblind and those that are unfamiliar with English.

Eventually, converting to a system where color is a secondary identifier, especially as DC adds more lines, will be necessary.  Particularly if DC adds track connections that enable more services, equating a line of track with the service that it operates on is limiting.  Eventually, DC should consider changing to a naming system similar to that of Paris – where the Metro lines are all assigned numbers and colors, while the regional RER lines all have letters and colors, with numbered suffixes for branch lines in the suburbs.  Jarrett Walker delves into the details of the Parisian system:

Actually, there are FOUR tiers of information here in a clever hierarchy, all designed to ensure that you don’t have to learn more information that you need to do what you’re going to do:

• A Métro route number signifies a simple, frequent line that doesn’t require you to learn much more, apart from riding it in the correct direction.
• An RER route letter such as Line A identifies the common RER segment across the core of Paris and invites you to use it exactly as if it were any other metro line, without caring about its branches.
• Odd vs. even numbered branch numbers on the RER indicate different directions on the common segment.  On Line A, for example, odd-numbered branches are all in the west, even numbered ones in the east, so as you get to know the service, the branch number tells you which way the train is going on the central segment.  Even if you’re not riding onto a specific branch, this can be useful, as redundant ‘confirming’ information, to assure you that you’re riding in the correct direction.  This is important as it’s very easy to lose your sense of north (if you ever had one) in the warrens of underground stations.
• Finally, the individual branch numbers are needed ONLY if you’re headed for a specific suburb beyond the branch point, such as Marne-la-Vallée.

The principle is that this is a progression from simple to complex.  The point of this hierarchy is not to lead customers all the way through, but exactly the opposite: to enable them to “get off,” ignore the remaining layers, as soon as they have the information they need.

Eventually, as DC aims to better integrate the commuter rail systems and further expands Metro, integrating brands and fare structures with Metro, a re-organization of the entire naming system might be in order.  With Silver and Purple lines on the way, there aren’t a lot of other options left.  When David at GGW looked at turning DC’s commuter rail lines into a sort of express Metro system, his naming system ran head up against the limitations (lime? teal?) of the color-based systems.

Hopefully, we’ll eventually have to deal with this issue.  It’ll mean that we’ve expanded and integrated our systems beyond what we have today.  More immediately, DC’s streetcar system presents some nomenclature challenges as well – and that will be a nice problem to have.