How transportation planning kills streets

Since the 1950s, the level of service (LOS) metrics have established an ideal condition for US thoroughfares. Think of a car commercial in northern Arizona with a road leading to the horizon with rock formations on either side (the rock formations are optional).

The opposite, the thing to be avoided at very high cost, is driving with lots of people all around you. That's called congestion.

That makes sense on an Interstate highway, but in a mixed-use downtown — not so much. In fact, there's a technical word for the absense of people in a city or town: Dead.

A far more technical and thorough explanation of why this is bad for cities can be found in Gary Toth's blog on the Project for Public Spaces website. It has some fun images by Andy Singer, which I repost below. The blog compares the use of level of service to weeding a flower garden with a rototiller.

Notice that after elimating the weeds and the congestion, the garden and the city are, respectively, dead.

Worse, Toth explains, the level of service metrics are combined with 20-year projections for the future. This method predicts growth and designs thoroughfares to avoid the dreaded congestion even in the face of the expected development for two decades coming. There's a technical term for a city or town without congestion for 20 years: Ghost town.

Of course, due to the lack of appeal of a community with overwide thoroughfares and a decimated downtown, the projected growth does not come. That's when even the ghosts look for a livelier place.

An alternative would be to create a new grading system that acknowledges that in some places — that is to say cities and towns — people are good. Mobility could be measured not in terms of how few people are around you, but how many choices you have to get from point A to point B. The best choice, really, would be walking a short distance on streets and through public spaces with lots of people all around you — places with life and ... congestion.

For more in-depth coverage on this topic: 

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