Dealing with Congestion

On September 8, Wiley & Sons will release the second book in the Strong Towns series: Confessions of a Recovering Engineer: A Strong Towns Approach to Transportation. Chapter 6 is about the shared experience of all American drivers with the seemingly wicked problem of traffic congestion. There is a reason for that ubiquity, as well as a reason why our efforts to end the scourge of traffic congestion have been unsuccessful.

French statesman Georges Clemenceau said, “War is too important to be left to the generals.” For our local leaders, traffic congestion is too important to be left to traffic engineers and transportation planners.

Back in 2015, when Congress was debating yet another transportation spending package, US Senator Chris Murphy took to Twitter to build support. He kicked off the conversation by focusing on the commute and invited people to share their ideas for how to fix it. He even live streamed his ride, sharing in the frustration of many who find themselves stuck in crippling traffic each rush hour.

Sadly, while Senator Murphy calls for an "honest discussion", his argument included this patently false statement right out of the Infrastructure Cult's talking points memo:

Federal gas tax receipts in 1993 were $19.6 billion. By 2013, that had climbed to $29.2 billion. To this, Congress annually adds billions more. The infrastructure bill currently being debated is unlikely to have a gas tax increase. Sure, the gas tax has not been increased since 1993, but let's not pretend that is the fundamental cause of our transportation woes or -- more importantly -- that what we "need" is more "big projects".

Most of Senator Murphy's Twitter conversation dealt with the chronic issue of traffic congestion. Notice I did not call congestion a problem. It's clearly not. Within our places -- on our streets -- congestion is an indicator of success. As Yogi Berra reportedly said:

"Nobody goes there any more because it is too busy."

Indeed. The most successful places are full of congestion.

Between our places -- on our roads -- congestion signals many things but, for me anyway, it primarily indicates America's cultural -- and the engineering profession's technical -- misunderstanding of the systems we have built.

Consider the hierarchical road network. It's so commonplace today that we rarely stop to question it. Small, local streets empty into collector streets. Those collectors empty into arterials. The arterials empty into major arterials which eventually end up pouring into our highway systems. Small to big; it's the way we build things in North America.

Slide from our Transportation in the Next American City presentation.

Slide from our Transportation in the Next American City presentation.

Stop a moment to ponder a watershed. There are ditches that flow into small creeks. Those creeks flow into larger brooks and streams. In turn these flow into larger rivers and, ultimately, these systems come together to form some of the world's major tributaries.

We all intuitively understand that, when we experience rain or snow melt on the edges of a watershed, there is a compounding effect that occurs. We are competent at recognizing that, by the time all this water is concentrated into a tributary, it can accumulate to produce a flood.

We've so grasped this concept that we've taken steps to address the problem in the only effective way possible: at the source. We don't allow people to fill their wetlands. We require developers to retain their runoff on site. We build retention systems to hold back stormwater and feed it into the natural systems more slowly so flooding does not occur. We take these steps and others at the source to mitigate the cumulative, negative impacts of stormwater runoff: flooding.

Slide from our Transportation in the Next American City presentation.

Slide from our Transportation in the Next American City presentation.

Instead of a river network, examine a similar system of roadways during a typical commute. Here we have rain of a different sort: the automobiles that emanate forth from the developments we induce, subsidize and cheer for out on the periphery of our cities.

The cars travel local streets, empty into collectors, then into arterials and major arterials, and then into our highway networks.

It’s Hydrology 101, so why are we so shocked when this produces a flood?

WE. CREATE. THE. FLOOD.

If we were going to design a system to generate the maximum amount of congestion each day, this is exactly how it would be done. This is why all American cities -- big, small and in between -- experience some level of congestion during commutes. We take whatever cars we have and funnel them into the same place at the same time. We manufacture a flood.

Like Hydrology 101, the only long-term way address traffic flooding is to go to the source. Auto trips need to be retained near where they originate, or transformed into non-auto trips, to prevent them from accumulating and flowing further downstream. We need to create local alternatives to an auto trip.

That means building more corner stores and neighborhood businesses. It means creating more local jobs and housing options. It means emphasizing sidewalks and biking infrastructure so that people have more alternative ways to respond to congestion. These things are also good and necessary outcomes if our cities are to become financially strong and resilient.

Traffic congestion was last century’s problem, but it is this century’s solution. Traffic congestion accelerates demand for local alternatives, the stuff we need to be building. We can’t build our way out of congestion if the only building we do is more transportation infrastructure, but if we expand our toolbox to include building more complete and prosperous neighborhoods, then traffic congestion becomes the catalyst for a renewed local prosperity.

For a nation of insolvent cities, the struggle against traffic congestion is over. The struggle to build stronger places is upon us, and in that, traffic congestion is now our ally.