Aerial view of collapsed sections of the Cypress viaduct of Interstate Highway 880 in Oakland, California in 1989. (H.G. Wilshire, U.S. Geological Survey)
Strange how the traditional laws of supply and demand go out the window when it comes to traffic. Studies over the last decade (like this one, this one, and this one; plus the book Suburban Nation) have pretty much dismantled the theory that more roads equal less traffic congestion. It turns out that the opposite is often true: building more and wider highways can increase traffic congestion. If only people like Robert Moses and Le Corbusier had known this before their grand urban plans left our cities clogged with traffic, and carved up by ugly, value-destroying highways.
As part of its series on urban transportation, the Mother Nature Network has this recent post, which includes a nice rundown of the evidence against highways as congestion relievers, plus a discussion of the latest idea taking hold in urban traffic management circles: destroy highways to reduce congestion.
A particularly dramatic case in point comes to us from traffic-clogged Seoul, Korea, where a few years ago a handful of “crazy” visionaries in the transport department somehow managed to sell a new mayor on the demolition of an elevated downtown highway. Fast-forward to today: the highway’s gone, a formerly paved-over river has been rehabilitated, the resulting green space is a source of urban pride, and — wait for it — motor vehicle travel times have actually improved in the neighborhood of the old highway.
The MNN piece reminds us that highway tear-downs have had similar results in New York City and San Francisco, but that it took natural disasters for those to happen: New York’s West Side Highway collapsed under the weight of a cement truck in 1973, and San Francisco’s Embarcadero Freeway was removed after suffering damage from the Loma Prieta earthquake in 1989.
One final tidbit on the economic costs of traffic: according to the Texas Transportation Institute, traffic congestion costs us $87 billion a year in wasted fuel. And that’s not even counting all those hours lost (and road rage)!
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The theory takes an interperetivist approach at explaining phenomena that have occured on auxilliary highways in huge metropolitan areas. If you remove the road, the demand for travel still exists. In the case of a large metro area with many alternative routes, removal of one may not affect the system’s ability to meet demand, but in a smaller area, removal of the highway could be crippling. Throughout CA’s central valley, populous areas have popped up along the highway since the inception of the interstate system. These cities that were built around the highways lack the supporting street framework to give people the same amount of mobility in the absence of the highway. If no alternative were created, people would be forced to find work and schools much closer to home, but more realistically, they would languish in their inability to get anywhere on the clogged country roads. Large cities offer legitamate alternatives to the highway (if nothing else, the opportunity for lifestyle change), but take the cross-town route from Fresno or Bakersfield, and the cities would descend into chaos.
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I am a transportation planner in California, and I am a little miffed at Mr. Turner’s article. First of all, he counters what he represents cartoonishly as a “one size fits all” solution with another, equally absurd proposition. If he were to look at travel demand models for every region that he proposes should be freed of its highways, he would find a great many where his theory does not hold. Highway deparments of 40 years ago severely misunderstood mobility, this is true, but “transportation planning” is a creation of the 90′s, and the engineers and planners still have a wasy to go before they see eye to eye. That brings me to my second point: planners at State DOTs and regional transportation agencies are constantly pushing for innovative alternatives to the highway. The planning process is backlogged by about 15 years by design, which means we are only now seeing the fruits of planners’ struggles since 1992. Look at the regional plans of the last decade and you’ll see that things are in flux, but it will still be years and years until the construction culture catches up. Turner’s postmodern “smash it to smithereens” take on the subject is cute, but devoid of any credit to the people who are actually trying to take what we already have and make it better and more efficient (a staple of sustainability, I might add).
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Lol. “traffic demand models.” the ones that are rigged to conclude more supply is always necessary? Like or don’t like this article because it supports or contradicts your assumptions, pick up Traffic by Tom Vanderbilt for a deeper view of the issues.
What happened in the cases cited above as well as in Seoul and Milwaukee which removed a freeway b/c they couldn’t afford to maintain it (expect far more of that around the country), resulted in improved overall connectivity and spatial integration as freeways are about regional to regional connectivity, undermining local connectivity, the backbone of cities.
Furthermore, what occurs is a form of “import replacement.” more things are done locally, now that a freeway is removed, a place becomes safer and more desirable, thus denser and more valuable.
Think about these examples as well. Pompidous widened the car travel lanes essentially from building face to building face. It pushed out all the pedestrians and all the businesses died. Since the mid 90s, Paris has systematically been replacing the travel/parking lanes of Champs Elysees along the side with increased pedestrian space. It’s now some of the most valuable real
estate in the world.
When Copenhagen began removing cars and parking spaces all of the businesses objected. They’re doing better than ever today because people want to be there.
And lastly, it is important clarify the difference between intracity and intercity freeways. The intercity are important in linking regional economies. The intra are destructive and disrupt local economies. This is why Eisenhower was appalled when cities and states bastardized his interstate system and ran amok with them.
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“motor vehicle travel times have actually improved in the neighborhood of the old highway”
Isn’t the point of a freeway to improve travels time to points that AREN’T in the neighborhood? Erecting a wall around each neighborhood would presumably also improve local travel times, but would greatly increase travel time to non-adjacent neighborhoods.
If eliminating freeways is such a great idea for large cities, then why don’t more rational commuters avoid the current freeways and use existing “surface” streets?
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Because many (most?) commuters – no, make that most drivers – aren’t rational?
If asked, I can provide plenty of observational evidence to support this thesis
If there were no roads, there would be no congestion on a road.
It’s simple supply and demand. You decrease the capacity of your road network (supply), and the cost of driving goes up (price), and demand goes down.
The question is whether the region is better off in some obscure measure, like happiness.
That’s a hell of a coincidence! On December 15, 1973, the northbound lanes between Little West 12th Street and Gansevoort Street collapsed under the weight of a dump truck, which was carrying over 30 tons (27,000 kg) of asphalt for ongoing repairs of the highway, too!
Traffic is caused by intersections, on and off ramps, and the forced changes in speed of vehicles. That’s just simple math.
Fascinating! I’d like to see how public transport and other projects impact congestion too.
Like many of the commenters I agree that the article ignores the ‘unseen’. Reducing capacity may reduce congestion, by people travelling less. But on the margin it may mean someone giving up work. Or instead of commuting into a city they may travel outwards out (maybe a longer journey but quicker). Or they may rent a city centre flat during the week, pushing up rental prices. Or the congestion may simply move elsewhere.
Surely the best approach is to estimate the external costs of motoring (CO2, congestion, pollution, accidents, lack of exercise, noise….. ) and tax accordingly. This may give you car taxes like here in the UK (if my sums are right I’m paying the equivalent of $7 per US gallon for fuel). Charge those costs, see how much traffic you get, plan accordingly. Job done. But of course it would be political suicide to even suggest it.
“…if my sums are right I’m paying the equivalent of $7 per US gallon for fuel…”
But you are probably paying as much per mile as the typical American SUV owner does when gas is $3.50/gal.
Good point James. If the US doubles gas prices and moves to efficient cars, it may not improve congestion. But it may not have to worry so much about what happens in the Middle East.