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Remember a few years ago when millions of our fellow Americans started gorging on bacon and cheeseburgers in order to lose weight? The Atkins diet fad was an odd moment in our culture and probably one best politely forgotten. But one reason the scheme took off like it did is that human beings are innately fascinated by counter-intuitive effects. Most examples you hear about on teevee–”Rock-hard abs without getting off your couch!”–are malarkey, of course. But in certain charmed cases, it is possible to get thin by eating lard, so to speak.
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One example is reducing traffic congestion by eliminating roads. Though our transportation planners still operate from the orthodoxy that the best way to untangle traffic is to build more roads, doing so actually proves counterproductive in some cases. There is even a mathematical theorem to explain why: “The Braess Paradox” (which sounds rather like a Robert Ludlum title) established that the addition of extra capacity to a road network often results in increased congestion and longer travel times. The reason has to do with the complex effects of individual drivers all trying to optimize their routes. The Braess paradox is not just an arcane bit of theory either – it plays frequently in real world situation.
Likewise, there is the phenomenon of induced demand – or the “if you build it, they will come” effect. In short, fancy new roads encourage people to drive more miles, as well as seeding new sprawl-style development that shifts new users onto them.
Of course, improving congestion is not the main reason why a city would want to knock down a poorly planned highway–the reasons for that are plentiful, and might include improving citizen health, restoring the local environment, and energizing the regional economy. More efficient traffic flow is just a wonderful side benefit.
Sound dubious? Here are several examples of how three cities (and their drivers) have fared better after highways that should never have been built in the first place were taken down.
CASE 1: Seoul, South Korea – Cheonggycheon highway
In 2002, Mayor Lee Myung Bak pledged to renew South Korea’s capital Seoul by eliminating a 1970s-era highway that literally represented a paving over of the Cheonggyecheon River. His radical plan replacing it not with another road, but with a restored stream along the old riverbed. The immediate result of the intervention was a beautiful new 1000-acre park in the center of the city, lower pollution, cooler temperatures city-wide. What wasn’t expected, however, was the city’s reduced traffic volumes. After all, the road carried 160,000 cars a day before it was closed. But the highway’s closing was enough to convince thousands of people to drive less, or change their habits, as the city offered better public transportation options.
Before:
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After:
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CASE 2: Portland, Oregon – Harbor Drive
The idea that it’s possible to remove a major road without creating traffic jams is not exactly a recent one: Portland proved its merits more than 30 years ago. Until the early 1970′s–a period when the city’s now-thriving downtown area was losing the battle with urban blight–there was a four-lane freeway known as Harbor Drive occupying the western shore of the Willamette River, creating a barrier between the downtown area and the waterfront. Even citizens and a few politicians began arguing in favor of taking down the road in the late ’60s though, Oregon’s Highway Department wanted to widen the thoroughfare.
Ultimately, the most important advocate for its demolition was then-governor Tom McCall. After a long and contentious political battle, McCall prevailed and the highway was closed in 1974. On the first day it was shut off to traffic, one of the highway engineers who predicted gridlock catastrophe reportedly called one of McCall’s lieutenants to congratulate him: there hadn’t been “a ripple” of disturbance in the city’s traffic flow.
By 1978, a greenway occupied the land where the Harbor Drive once stood. Twice expanded since then, the Tom McCall Waterfront Park is an integral part of Portland’s success in recreating itself as a 21st century city.
Before:
(Photo)
After:
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CASE 3: San Francisco – Embarcadero Freeway
Arguably the US city where freeway removal has most improved urban life is San Francisco. The Embarcadero Freeway once stood elevated on the city’s waterfront. Two levels of concrete divided downtown from the bay. Though there had been a public push to demolish it since it was constructed, only after it was damaged in the 1989 Loma Prieta earthquake did the efforts crystallize, and it was never rebuilt. In its place today: a waterfront boulevard with bike trails, parks, and public exhibitions.
Before:
After:
(Photos)
CASE 4: San Francisco – Central Freeway
Also damaged in the Loma Prieta quake was the Central Freeway, which ran as a spur into the city. The thoroughfare was closed in 1992 and a few years ago rebuilt as a surface road named Octavia Boulevard. Though the boulevard is well-used, it’s no more congested than the far larger highway that it replaced, showing that traffic responds the environment in which it is placed.
Before:
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After:
Of course, this evidence doesn’t suggest that all road expansions are unnecessary, or that all highways should be removed. All of the highway demolitions cited above are in densely packed urban areas where other highways and reliable and convenient public transportation options are available. But the lesson is clear: If a major road is making a city a less livable and vital place that it would otherwise be, in many cases everyone benefits when politicians have the vision and guts to tear it down.
COMING THIS WEEK: Roads to Tear Down, Part 1
Tags: FEATURE
[...] Huh?! 4 Cases Of How Tearing Down A Highway Can Relieve Traffic Jams (And Save Your City) [...]
[...] for a different future—New York, London, Paris, Seoul, Copenhagen, San Francisco. Together, their successes show that it’s possible to relieve congestion, create beloved vibrant streets, grow the economy, [...]
[...] stays at home. As with others cities, Philadelphia should consider dismantling its highways (see: Braess Paradox), and should reject any federal attempt to build more roads. For the annual capital required for [...]
[...] stays at home. As with others cities, Philadelphia should consider dismantling its highways (see: Braess Paradox), and should reject any federal attempt to build more roads. For the annual capital required for [...]
[...] stays at home. As with others cities, Philadelphia should consider dismantling its highways (see: Braess Paradox), and should reject any federal attempt to build more roads. For the annual capital required for [...]
The Buffalo Skyway is a particularly good example. It’s not even terribly busy *now* thanks to Buffalo’s shrinkage — there’s absolutely no excuse for it.
Another cute example of closure *improving* traffic is Times Square. Broadway knots up the entire traffic pattern in Manhattan; closing it at all the intersections with north-south streets speeds traffic up. And people like it, too!
[...] The answer may, perhaps, lie with the Alaskan Way viaduct, and how Seattle is dealing with it’s aging. The notable cultural phenomenon that both Vancouver and Portland share (but Seattle does not) is a rejection of freeways. [...]
Yes, some research on Traffic Reduction -
On this page are two items:
http://www2.cege.ucl.ac.uk/cts/tsu/publications.asp?StaffID=33
1. 2002 Disappearing traffic: the story so far
Have a look at page 4 for a list of road closure effects.
Some were involuntary, such as bridges falling down.
2. 1998 The summary of the full study:
Traffic impact of highway capacity reductions: assessment of the evidence
I just wanted to say thankyou for posting this. I was a throughly enjoyable read and certainly opened my eyes to allot of things that I had not thought about before. Look forward to more from you.
[...] final lighter note – this is a really interesting article looking at some examples of planners axing roads in favour of public spaces, and finding relatively [...]
Freeways, even roads in general, are an abomination to humanity in that they fundamentally remove humanity from urban spaces–roads are commutation zones, thought of as places that you don’t want to spend more than a few seconds to avoid getting hit. Only rarely during “special” events, i.e. parades and open markets, do streets become communicative environments. The freeway is the epitome of the void, as it is wholly devoid of
This is the reverse of what the street was, for all of human history excepting the past 80 years–the marketplace, the forum, the public square, all of this happened in the street. Now our humanity is confined to small strips of concrete sidewalk, subordinate to the car-dominated landscape.
The urban future will be radically different than the Jetsonesque landscape we all once imagined; a gradual shift is taking place in which we realize that individualized hermetically sealed boxes are actually a pox on our landscape and psyche, and that cars should be subordinate to US, not the other way around.
The Gardiner Expressway, Toronto, has been under threat for many years.
The reason has to do with making Lake Ontario more visible from Toronto’s downtown area. Some people complain that the Gardiner, which is an elevated highway, blocks the view. There have been extravagant plans to bury the Gardiner, by rebuilding it underground. There is also a plan to convert part of it into a ground-level boulevard, replete with stop lights and pedestrian crossings. So far only a short stretch at the east end of the Gardiner has been demolished.
What some people may have forgotten is that Toronto adopted a policy of limiting highway construction, culminating in the cancellation in 1971 of the proposed Spadina Expressway along with a number of other proposed highways in Toronto. See
http://en.wikipedia.org/wiki/Spadina_Expressway and
http://en.wikipedia.org/wiki/Cancelled_expressways_in_Toronto
Urban planner Jane Jacobs, who had been instrumental in blocking the Lower Manhattan Expressway in New York City, blamed the construction of expressways into major American cities for an exodus of the middle class from once-vibrant downtown cores. Jacobs formed the “Stop Spadina And Save Our City” group, which grew to become a major rallying point for anti-expressway feeling in the city. By the late 1960s the Spadina Expressway had become a “hot” topic politically.
The Spadina decision is history and most unlikely to be reversed. However not many people seem to appreciate how poorly served Toronto is by expressways, compared with most other cities of comparable size, especially those in the USA. Just two expressways serve the downtown area, the Gardiner Expressway and the Don Valley Parkway, and they are connected in such a way as to form a single highway.
Compare these two with the number of highways serving Dallas or Houston, cities of about the same size, each of whose downtown areas can be approached by a choice of about seven expressways and whose downtown areas are surrounded by ring roads to help to distribute the traffic.
On no account should the Gardiner Expressway be demolished. It’s far too useful and any replacement would be far too expensive.
[...] a handful of cities have been willing to tear down a bad highway and start again. In the end, they’ve succeeded, because they’ve been willing to deal with the short-term effects to ultimately deliver a [...]
I like boston’s idea with i-93 its the best of both worlds there’s a park and the freeway is underground! Oh and I give thanks to the rest of the american citizens for helping split the 60/40 bill on the project. I know its not fair having to pay such a crazy amount of capital to improve a city that you dont have residence within.
$22 billion for Boston’s CA/T project pales in comparision to the trillions being spent upon the post 911 wars- which off course utterly neglect civil defense-evacuation route needs which would jusify numerous undergound highway and rail projects, though uttery ignored by the jesuitical-masonic elites and most of the impressionable college students.
[...] maintaining excess auto lanes, adding new lanes, or refusing to give up lanes for other modes. Entire highways have been torn down and replaced by at-grade, multi-modal boulevards, or in some cases streams and [...]
Am I the only one that finds river/harbor walks to be bland and visually lifeless? They have no more character than a room at the Hilton. At least raised highways, like the Embarcadero had a kind of aggressive, almost exuberant, expression of utility and an aesthetic true to its purpose. The only highway reclamation projects I like are the Cheonggycheon highway which has introduced vegetation and water to create a complex and changing organic scene, and the San Francisco central freeway transformation, which actually looks like a genuine streetscape. As for replacing harbor freeways with boat basins, I find this loathsome. To me, a yacht basin is just another ugly parking lot, to which only the wealthy may apply. What makes cities interesting to walk through and live in is fairly close to what makes them unbearable: an organic, decentralized mixture of old and new things, rehabilitation and decay, competing interests, responsiveness to pedestrian and consumer needs and multiple layerings of usage. When planners come along, they tend to favor some interests over others, and tend to clean up and obliterate some of the more interesting elements of the cityscape. Riverwalks have no competing interests, little evidence of “layering” except in statically managed museum-like displays, and a lack of responsiveness to the user. I am not opposed to regulations to curb excesses like pollution, noise, obstructions to public passage, and infrastructure projects designed to improve transportation, improve living conditions and civic health. But, I recognize that planners are notoriously poor at understanding or replicating the “dynamic tension” (Jane Jacobs) that makes cities vital.
[...] zone when the next bus rapid transit (BRT) phase is installed. Interestingly, there have been many studies showing that traffic does not deteriorate when public space is added – even a mathematical [...]
[...] Cities that have chosen (or been forced by citizen groups) to stop building or to remove freeways have been rewarded tremendously, and not just economically. [...]
[...] is a counter-intuitive fact that several cities have removed urban freeways without signficant effects on auto traffic elsewhere, while improving the overall quality of life [...]
It’s amazing how beautiful and simple this can be. It’s also amazing the ideas they have to help lower the congestion in the city.
[...] – from infrastructurist.com [...]
[...] there is, as the phrase has it, a better way. From Seoul to San Francisco, the urban motorways are coming out (thanks to Jonny for that [...]
[...] antithetical but if you tear out a highway, you might just relieve congestion. This article by The Infrastructurist gives four examples of exactly how that [...]
[...] Francisco went through a similar transformation with its Embarcadero Freeway. Although the freeway’s actual demolition didn’t come to fruition until damage from a 1989 [...]
[...] Francisco went through a similar transformation with its Embarcadero Freeway. Although the freeway’s actual demolition didn’t come to fruition until damage from a 1989 [...]
[...] in their downtown cores. This is just the first Google hit on "highway removal": Huh?! 4 Cases Of How Tearing Down A Highway Can Relieve Traffic Jams (And Save Your City) | INFRASTR… This is why so many Portlanders are against the building of the new Columbia River Crossing. [...]
[...] no more LIE? No more GSP? No more VWE? The city will just be one huge parking lot. Read this: Huh?! 4 Cases Of How Tearing Down A Highway Can Relieve Traffic Jams (And Save Your City) | INFRASTR… Is Removing a Major Road Really a Good Idea? | INFRASTRUCTURIST Seoul tears down an urban highway [...]
[...] cities such as San Francisco, Portland, and Seoul have found that tearing down freeways has actually reduced congestion while improving business (and of course life on the [...]
I support the demolition of flyovers in CBD. But diverting traffic around CBD and reducing congestion in CBD is not the real meaning of Braess Paradox. Are there any real measured evidence of it? Is it possible to measure it? I do not think that is really possible. I am trying to do it with well calibrated network model. Anyone has the experience please contact me.
Ho take from me a little pussycat ? see video
[...] across the country (and globe) have decided that urban freeways could be turned into parks and development opportunities. In [...]
[...] across the country (and globe) have decided that urban freeways could be turned into parks and development opportunities. In [...]
[...] The answer may, perhaps, lie with the Alaskan Way viaduct, and how Seattle is dealing with it’s aging. The notable cultural phenomenon that both Vancouver and Portland share (but Seattle does not) is a rejection of freeways. [...]