Basics

basics: the “new route” problem

When people think of a new transit need, they often jump prematurely to the idea that they need a new route.  This article of mine — linked to in Chapter 7 of my book — explains why this can be a bad idea.

network design for high ridership, a dense city example

How do transit network designers go about their task? Surprisingly little has been written about this.  You can pick up books that appear to cover the “network planning” process and find examples of good and bad networks but rarely a description of how to do the design thinking itself.  EMBARQ’s recent manual for network planners in India, for example, provides great detail about how to analyze demand and evaluate results, but show no awareness of the really challenging task of network design, which sits in between those tasks. Continue Reading →

basics: dead running

P1010471 The British/Australian term “dead running” means “running out of service, unavailable for passengers.”  I like the term because it could be the title of a zombie movie.  I look forward to seeing if it attracts hits. Continue Reading →

basics: walking distance to transit

The question of walking distance in transit is much bigger than it seems.  A huge range of consequential decisions — including stop spacing, network structure, travel time, reliability standards, frequency and even mode choice — depend on assumptions about how far customers will be willing to walk.  The same issue also governs the amount of money an agency will have to spend on predictably low-ridership services that exist purely for social-service or “equity” reasons. Continue Reading →

how universal is transit’s geometry?

240px-Uranus2 Suppose that somewhere else in our universe, there’s another planet with intelligent life.  We don’t know what they look like, or what gases they breathe, or what they eat, or whether they’re inches or miles tall.  We don’t know whether they move by hopping, drifting, or slithering.  We don’t even know if their lived environment is largely two-dimensional, like the surface of the earth, or freely three dimensional, perhaps a cloud-city full of cloud-beings who drift up and down as easily as they drift left or right.  We don’t know what they call themselves, so let’s call them borts. Continue Reading →

basics: branching (or how transit is like a river)

A short draft chapter from the book, overlapping the content of this recent post but with an extended BART example that I hope readers will enjoy and have comments on.

In 2011, cartographer Daniel Huffman thought it would be interesting to draw river systems as though they were subways.  Figure 1 shows part of his sketch of the Lower Mississippi.[i] Continue Reading →

basics: expertise vs. activism

The planning professions work in a grey zone between expertise and activism, and managing these competing impulses is one of our hardest tasks.

As a transit planning consultant, I don’t worry much about being perceived as an advocate of transit in general.  Experts in any field are expected to believe in its importance.  But I do try to keep a little distance between my knowledge about transit and the impulse to say “You should do this.”  A good consultant must know how to marry his own knowledge to his client’s values, which may lead him to make different recommendations than he would do as a citizen, expressing his own values. Continue Reading →

basics: conceptual triangles

Sometimes, we have to think in triangles.

In the transit world, for example, we know that ridership arises from a relationship between urban form (including density and walkability) and the quantity of service provided.  For example, if we focus on local-stop transit, the triangle looks like this: Continue Reading →