Calming Traffic on Bogotá's Killing Streets by cuiliqing


      make better use of energy, water, and materi-        owned by the municipal government’s Shang-           planned ecological footprint could be less
      als to minimize a building’s environmental           hai Industrial Investment Corp. The city wants       than half that of a comparable conventional
      impact throughout its life cycle. These trends       housing for 10,000 residents completed in            city, Wood says. Buildings will be properly
      are converging in plans for several eco-cities,      time for Shanghai’s 2010 World Expo, which,          insulated and rely on low-energy lighting
      the most notable being Dongtan.                      appropriately, will explore the theme “Better        and appliances. A double-piping system will
         From the outset, the Shanghai govern-             City, Better Life.” The goal of the start-up         provide drinking water and treated waste-
      ment, which owns the site, has viewed                phase, scheduled for completion by 2020, is a        water to flush toilets and irrigate vertical
      Dongtan as an “eco demonstrator” of urban            community of 80,000, businesses providing            farms (see p. 752). The initial target is that
      development existing in harmony with the             50,000 jobs, and shops, entertainment, and           no more than 10% of Dongtan’s trash will
      environment—even on an ecological treas-             cultural amenities that offer residents every-       end up in a landfill; planners would like to
      ure like Chongming. “This is not just about          thing they need in Dongtan, although it’s            eventually make it the world’s first zero-
      saving energy or saving water,” says Roger           expected that some people will commute to            waste city. Most Chinese cities dump about
      Wood, a partner in the engineering consult-          Shanghai and some nonresidents will work in          90% of their waste and burn the rest.
      ing firm Arup in London that is in charge of         Dongtan. Eventually, the Eco-city could be               A second requirement is that all energy
      Dongtan’s master planning. “It is about a            extended to cover 30 square kilometers and           consumed in Dongtan comes from renewable

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      holistic approach that goes right through the        house half a million people.                         sources. Solar panels, wind turbines, and a
      social, governance, education, transporta-              The investment corporation instructed             biomass cogeneration plant, fueled by rice
      tion, wastewater issues—all the things that          Arup to minimize the project’s ecological            husks, will generate electricity for power,
      actually make a community.”                          footprint: the land and water areas needed to        heating, and cooling. Husks, currently burned
         Dongtan will rise on a portion of an              provide Dongtan’s resources and absorb               or dumped, will be collected from throughout
      86-square-kilometer strip of Chongming               waste. Using established technologies, the           the Yangtze delta.

      Calming Traffic on Bogotá’s Killing Streets
      With humor, education, and tough laws, this Colombian city has dramatically reduced traffic injuries and deaths
      LONG BRANDED AS ONE OF THE WORLD’S MOST DANGEROUS CITIES, changes, deaths and injuries would increase 65% by 2020. “We have
      Bogotá, Colombia, has won plaudits for cutting its murder rate by more than interventions that work, and we know how to bring the rates down,” says
      70% during the past decade. But this city of 7 million people has received far Rosenberg. “There’s no other opportunity like this in public health. It’s as
      less attention for a dramatic decline in a more com-                                                   good as the best vaccines. But we need the
      mon danger that plagues urban areas everywhere:                                                        resources”—and political will.
      traffic-related injuries and deaths.                                                                       Rosenberg, Hildalgo, and others laud the
          With a combination of innovative education                                                         aggressive and creative efforts of mayors Antanas
      campaigns, an overhaul of its public transporta-                                                       Mockus and Enrique Peñalosa, who alternately ran
      tion system, strict law enforcement, and redesign                                                                                   the city from 1995 to
      of streets and highways, Bogotá has made mov-                                                           Silent treatment.           2003. Mockus, a former
                                                                                                              Bogotá used mimes to
      ing from place to place safer and more efficient.                                                                                   mathematician and
                                                                                                              shame traffic violators.
      “In 1997, everything was a mess and we were los-                                                                                    philosopher, famously
      ing the battle,” says Dario Hildalgo, a trans-                                                         painted zebra stripes at intersections and

                                                                                                                                                                     PHOTO: COURTESY OF EL TIEMPO; SOURCE: ROAD ACCIDENT PREVENTION FUND
      portation engineer from Bogotá who is now with                                                         employed mimes to shame bad behavior, pretend-
                                                              Bogotá Traffic Safety History
      the World Resources Institute in Washington,                                                           ing to pull on vehicles, for example, that blocked
      D.C. “To solve the problems, we needed a mira-                      Accidents Deaths      Injuries     crosswalks at red lights. “The city was a very funny
      cle. The miracle happened.”                                                                            place,” says Francisco José Fernandez, head of the
          Mark Rosenberg, the former head of injury pre-       1998       52,764     914        21,053       Road Accident Prevention Fund, a private group
      vention at the U.S. Centers for Disease Control and      1999       52,327     872        22,035       supported by a special tax on car insurance. But
      Prevention in Atlanta, Georgia, says Bogotá is a         2000       48,337     823        22,035       Mockus had serious aims and some decidedly
      model for the world. “Bogotá is not unique in hav-                                                     unfunny interventions. For one, he fired approxi-
                                                               2001       42,776     764        24,265
      ing this problem, but it is unique in solving it,” says                                                mately 2000 traffic police. “The police department
      Rosenberg, who now heads the nonprofit Task              2002       41,615     604        22,289       that was working on traffic was very corrupt,” says
      Force for Child Survival and Development in              2003       40,175     759        22,884       Fernandez, who served as secretary of transit when
      Decatur, Georgia.                                                                                      Peñalosa took over in 1998.
                                                               2004       43,000     666        24,532
          In a 2004 report, the World Health Organiza-                                                           Peñalosa, an erstwhile journalist, built on
      tion and the World Bank blamed 1.2 million deaths        2005       35,838     564        17,249       Mockus’s efforts. Bogotá hired an army of 1000 to
      and some 50 million injuries each year on road           2006       35,585     553        17,815       confront pedestrians who ignored red lights,
      crashes. For people between the ages of 10 and 24,       2007* 31,083          486        15,029       cracked down on drunk drivers, built bicycle-only
      traffic injuries are the leading cause of death                                                        lanes, installed new signals, and restricted each
      worldwide. The report projected that without major       * Through October.                            car’s access to the city center to 2 workdays a week.

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                                                                            Published by AAAS
                           The plan also calls for all vehicles in         detached home. One unresolved issue likely to             As they wait for Dongtan to materialize,
                       Dongtan to have zero tailpipe emissions. That       affect car use is whether the rail line connect-      planners welcome growing efforts to reduce
                       will be a stretch technologically, and it will      ing Chongming to downtown Shanghai will               energy and resource use, a trend that Qiu says
                       require a mind shift in middle-class aspira-        extend to Dongtan. Deng says previous new             will be furthered by several new national laws
                       tions. Dongtan planners hope to reduce              towns lacking good public transportation              on planning and energy consumption. In
                       dependence on private autos with apartment          links ended up encouraging private-car use.           addition, Shanghai, to alleviate traffic and
                       buildings laid out in clusters so that all resi-        There are other concerns. Zhu Dajian, an          promote mass transit, is considering a toll
                       dents are within a 10-minute walk of a shop-        economist who studies sustainability at Tongji        system on private cars entering downtown,
                       ping center and public transportation, which        University in Shanghai, says it will be a chal-       similar to schemes in London and elsewhere
                       could be pollution-free fuel-cell buses or elec-    lenge turning Dongtan’s impressive plans into         (see p. 750).
                       tric light rail.                                    reality without compromises: “The key issue is            China’s urban planners realize that eco-
                           Cars running on fossil fuels cannot achieve     that the implementation is often out of the con-      cities, redevelopment projects, and green
                       zero tailpipe emissions, so conventional cars       trol [of the designers].” Zhu adds that although      building efforts must be scrutinized to deter-
                       would have to be parked outside city limits.        some of Dongtan’s concepts and technologies           mine how well they enhance livability and
                       Dongtan residents who wish to drive in town         could be put to use in other projects, he thinks it   reduce environmental costs, Qiu says. With so

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                       will have to use hydrogen fuel-cell or electric     will be difficult to copy the model wholly            many cities growing so rapidly, China is
                       vehicles. However, such vehicles that match         because of Shanghai’s financial and institu-          already a laboratory for urbanization. Now it
                       the performance and affordability of conven-        tional support for Dongtan. (Officials at Arup        is poised to become an experiment in innova-
                       tional cars are years if not decades away. Zhao     say they are unable to disclose estimated costs       tive urban planning as well.
                       wonders if enough people will be willing to         or how the costs compare to those of a conven-                                           –DENNIS NORMILE
                       give up the dream of owning a car and a             tional new town.)                                     With reporting by Richard Stone in Xiamen.

                           Perhaps most important, Peñalosa championed a new bus
                       rapid transit system modeled after the widely celebrated one in
                       Curitiba, Brazil. At the time, Bogotá relied on several bus com-
                       panies that clogged the roads and vied for passengers.
                       Peñalosa oversaw development of a bus rapid transit system
                       called TransMilenio that has dedicated lanes. He also forced
                       companies to work together by bidding for contracts and shar-
                       ing revenue. Although Peñalosa met strong resistance,
                       Hildalgo, who worked on TransMilenio, says the mayor told the
                       bus companies, “I’m doing this with you or without you.” When
                       Peñalosa’s term ended in 2001, Mockus was reelected and
                                                                                                                                                    Fast lane. Bogotá
                       continued the traffic reforms.
                                                                                                                                                reduced traffic injuries
                           Today, TransMilenio has only about 25% of its projected                                                           and deaths by replacing a
                       388 kilometers in operation—funding shortfalls have slowed                                                             chaotic, competitive bus
                       completion—but accounts for 18% of the transit trips in the                                                           system with TransMilenio,
                       city and moves 1.3 million passengers a day. The $750 million                                                         which moves more rapidly
                       system has shaved about 15 minutes off the average trip,                                                                      and pollutes less.
                       according to TransMilenio data, and has reduced emissions by
                       replacing 1500 obsolete buses with a new fleet.
                           TransMilenio is one element in a broad push to improve traffic safety.         In April 2006, the World Bank launched the Global Road
                       Along the TransMilenio route, injuries plummeted from 18 a week in 1998        Safety Facility to help low- and middle-income countries reduce traffic-
                       to four in 2002, notes Hildalgo. In Bogotá at large, accidents and traffic-    related injuries and deaths. The fund hopes to spend $30 million per year,
                       related injuries and deaths all steeply dropped between 1998 and 2006 (see     but to date, donors have contributed just $12 million. “It’s nothing,”
                       table, p. 742).                                                                complains Rosenberg.
                           Bogotá proves that even cash-strapped cities can improve traffic safety,       As much progress as Bogotá has made, it, too, faces costly obstacles to fur-
                       Rosenberg says: “Traffic deaths are not an essential consequence of growth     ther improving its traffic safety. The new mayor, Samuel Moreno Rojas, has
                       and development.”                                                              promised to build a traditional rail system, an idea that the public likes but
                           Elsewhere, Sweden has paced the field with technologies—such as            that some transportation experts worry will inevitably delay the completion of
                       road dividers made of Mylar—and traffic-slowing strategies as part of          the much cheaper TransMilenio routes. And although use of private cars has
                       Vision Zero, a project launched in 1997 to eliminate traffic deaths and        dropped, motorcycles are increasingly popular and now are involved in
                       injuries in that country. Traffic deaths, which already were low by interna-   51% of all fatal crashes. “Motorcycles right now are a nightmare,” says

                       tional standards, by 2006 had dropped by 20%. “Probably the most               Fernandez. Improving motorcycle safety, he says, will require intensive courses
                       important measure for bringing down the death rate is to build safer roads     for riders, more complex licensing tests, and stepping up enforcement—all of
                       so when people make mistakes in driving they’re not penalized with their       which cost money. “Bogotá is much more friendly now than it was 10 years
                       lives, and they did this in Sweden,” says Rosenberg. Norway and Australia      ago,” says Fernandez. “But there are a lot of things to do.”
                       now have similar programs.                                                                                                                       –JON COHEN

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