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Reducing Parking Spaces Helps Cities Cut Auto Emissions

A new study shows economic and policy changes that limit parking have significantly reduced miles driven in 10 European cities

With bicycle share schemes, smoothly running metros and pedestrian-only streets, Europe has an edge over the New World when it comes to alternatives to automobile transportation. A new study reveals that Europe has success with another tool designed to remove people from their cars: subtracting parking spaces.

Because every vehicle trip must end in a parking space, limiting parking through economic and policy changes has significantly reduced miles driven in 10 European cities, according to "Europe's Parking U-Turn: from Accommodation to Regulation," published by the New York City-based Institute for Transportation and Development Policy (ITDP).

On- and off-street parking is ultimately controlled by municipalities, and decisions at the local level can help boost citizens' adoption of car alternatives. In the cities studied, which range from Antwerp, Belgium, to Zurich, researchers assessed how parking policies have shifted to fit in with "alternative social goals," including walking, bicycling and increasing park and community space.


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"European cities demonstrate that if you make a city center more convenient, people won't think that driving is the best and only alternative," said Michael Kodransky, co-author of the study and global research manager with ITDP.

Optimally, parking lots should always be 85 percent full to help reduce cruising for a parking space, said the study. The coordination of on-street parking supply with off-street parking supply through pricing structures is essential.

Europeans try 'cap and trade' with parking
Shrinking the number of parking spaces also helps. Hamburg, Germany and Zurich implemented a kind of "cap and trade" of parking spots, where for every off-street spot built, an on-street parking spot was converted into park or community space. Many cities in the study also abolished minimum parking standards for new developments, instead enforcing a maximum allowance. Zoning planners also gave priority access to popular spaces to pedestrians and public transit users.

Paris even invested €15 million ($20 million in physical blocks like bollards to prevent cars from parking. London was the only city in the study to charge parked vehicles based on their level of carbon emissions.

The results are positive. Take Amsterdam, a city that saw a 20 percent reduction in car traffic in the inner city, as well as a 20 percent decrease in traffic searching for a place to park, since strict parking enforcements were implemented. In Copenhagen, Denmark, traffic dropped by 6 percent in five years, despite a 13 percent increase in car ownership over the same period.

Parking charges are less controversial than congestion charges -- a tax to drive in city centers during peak hours -- and more likely to pass in a vote, said Kodransky.

Dealing with parking is also politically challenging, he added, but the public is more likely to accept it if they know that the revenues will be used to make public spaces more pleasant -- in Barcelona, Spain, 100 percent goes to the bike share scheme, for example.

Parking regulations work best when done in concert with other policies, said Deron Lovaas, federal transportation policy director at the Natural Resources Defense Council.

"They have to be part of a package, and that has to be communicated to consumers," he said.

He added that the measuring of vehicle miles is a fair reflection of how emissions might stack up. "It doesn't make much sense to rank them in isolation," he said.

American cities mandate space availability
The fact that this study was done in Europe "points to the likelihood that there hasn't been much progress at all" in the United States, said Lovaas.

However, Donald Shoup, a professor of urban planning at the University of California, Los Angeles, says that some cities have shown efforts to reduce car use through parking enforcement.

One example is in Washington, D.C., where council member Tommy Wells introduced a performance parking pilot program almost three years ago that set higher meter rates around the city's baseball stadium.

"On every block there should be one vacant place," said Shoup. "If there's no vacant place, the price is too low."

Shoup is a leader in the field of limiting parking for smart growth. His 2005 book "The High Cost of Free Parking" has garnered ardent followers, or "Shoupistas," according to Lovaas.

He adds that city zoning rules have traditionally mandated a minimum amount of parking. Now, governments must instead demand a maximum number of spaces in order to cut car dependency.

"It isn't as though there wasn't any regulation; the regulation is to require a lot of parking," said Schoup. "We've been regulating badly; our regulations have done a lot of damage."

Reprinted from Climatewire with permission from Environment & Energy Publishing, LLC. www.eenews.net, 202-628-6500

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