Here’s a look at how tearing down highways is a good thing.

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.

Vehicles are being barred between 42nd and 47th streets at Times Square and 33rd and 35th Streets at Herald Square.
City officials say the move will reduce pollution and pedestrian accidents and ease traffic flow in the area known as “crossroads of the world”.
…
“It’s good for traffic, it’s good for businesses and we think it is going to be great deal of fun,” city transport commissioner Janet Sadik-Khan said last week.

The symbolism of the financial heart of the American empire discouraging the use of the automobile will hopefully be noticed.

In a three pronged study which evaluated drivers without a navigation system, drivers with a navigation system, and drivers with a navigation system that included traffic, the results revealed that drivers using navigation devices 1) drove shorter distances and 2) spent less time driving. Conducted in two metropolitan areas of Germany – Dusseldorf and Munich – the study also showed that drivers with navigation devices had a 12% increase in fuel efficiency, as measured by liters of fuel consumed per 100 kms. Fuel consumption among those drivers using navigation fell from 8.3 to 7.3 l/100kms.
This increase in fuel economy translates to an estimated .91 tons (metric) decrease in carbon dioxide emissions every year per driver, or a 24% decrease over the amount that the average non-navigation user emits per year. Stated in terms of grams/km the reduction equates to 25 g/km per car. And with an annualized decrease in driving of nearly 2500 fewer kilometers per driver, 1.19 million tires would also be saved from disposal in Germany due to the decrease in wear and tear.

“If the green trial proves successful, TNT will consider adding 200 additional zero emission vehicles to its fleet to serve in other urban locations in the UK. This would result in significantly reduced controlled and CO2 emissions.

TNT has an overall rating of 84 out of a possible 100 on the Dow Jones Sustainability Index, the highest recorded score in the Industrial Transportation category in 2006.”

Previously, we looked at an artistic display of this concrete.

“Visitors to the Italian Pavilion of the architecture exhibition in the Venice Biennale, which will remain open until Nov. 19, will get a breath of fresh air. That’s because parts of the concrete walls and grounds have been built with cement containing an active agent that, in presence of light, breaks air pollutants such as carbon monoxide, nitrogen oxide, benzene, and others through a natural chemical process called photocatalysis.”

“The agency estimates that by 2030, when most old engines will have been replaced, 20,000 premature deaths, tens of thousands of illnesses, and more than 7,000 hospital visits will be prevented every year.

Officials said cleaner diesel fuel will immediately cut soot emissions from any diesel vehicle by 10 percent. But when combined with new engines hitting the road in January, it will enable emission reductions of up to 95 percent. ”

The technology behind the tiles is still being tweaked. Essentially, the tiles absorb pollutants that are generated from cars that lead to smog, while letting other gasses float on by. The tiles need to be located near the pollution source in order to be the most effective of course.

“The tiles provide councils, developers, and designers with an easy way simultaneously to improve the air quality and visual appeal of urban spaces. A London- and Berlin-based, interdisciplinary collaboration between innovators and materials manufacturers, architects and city councils, Elegant Embellishments produces lo-tech, interactive tiles in all shapes and sizes together with Millenium Chemicals TiO2. The tiles are modular and can thus be assembled to cover any surface or create any shape desired.”

The BBC is running a good article on car sharing in the UK. Richard Ghail writes about how carpooling is a great way to meet people, save money and the environment all in one go.

He credits the congestion charge in London reinforces of environmental protection. What’s more, he points out that the economy benefits from less congestion on the road.