How to Keep 18 Million People Moving

São Paulo operates the world's most complex bus system

Photo: Julio Bittencourt


Buses form a convoy on the Francisco Matarazzo Avenue busway.

It’s a warm Tuesday night in São Paulo, and as on most nights during rush hour here, a swarm of cars clogs every centimeter of Rebouças Avenue, slowing traffic to a crawl. But inside bus 7598, Carlos Soares holds on firmly to keep his balance as the jolting vehicle whizzes past the congestion. The bus he’s on is one of thousands in this city that run in special lanes that cars are forbidden to use. Convoying one after the other, the buses form a kind of virtual train on tires.

”Look at their faces,” says Soares, a 20-year-old video producer, pointing at the drivers stuck nearby. ”They’re mad because the buses took one of their lanes. But for us on the bus--we love it.”

For the past five decades, congestion has gotten steadily worse in this Brazilian megacity, South America’s largest, with 18.3 million people scattered throughout its metropolitan area. Although Brazil may be better known for the vibrant beaches of Rio de Janeiro or the lush, green Amazon forest, São Paulo is this country’s economic locomotive. So plenty of people have thought long and hard about how to keep the city moving--literally. More subway and commuter rail lines are on the way, but they are coming slowly and at great expense. Seeking alternatives, transportation experts here turned to an option that was already on the streets: the bus.

With 26 391 buses, 1908 lines, 34 transfer stations, and 146.5 kilometers of dedicated busways, São Paulo operates what is currently the world’s most complex bus system. Extending from bustling downtown avenues to narrow neighborhood streets, this sprawling network of lines is the basis of public transportation here. One in every five paulistanos --as residents of São Paulo are called--hops on a bus every day to go to work, school, or other destinations. Daily bus rider­ship in the metropolitan area is some 10.5 million passengers. With such people-moving capacity, the entire population of Belgium could ride on São Paulo’s buses over the course of a single day.

In a transportation world that has dreamed up such systems as maglev bullet trains and ”smart roads” capable of guiding vehicles, bus-based mass transit may appear quite low-tech. But in São Paulo the buses themselves are only the most visible part of a vast operation that relies on a number of advanced technologies: computer simulations help plan the bus network, GPS monitoring keeps track of the fleet, and electronic payment streamlines fare collection. And in an experiment to reduce pollutant emissions, later this year São Paulo will test a small number of hydrogen-fuel-cell buses on one of the city’s busiest busways.

None of this technology would be of much use without experienced bus engineers, of whom São Paulo has plenty. Over the years this cadre of bus pros has been disseminating its expertise throughout Brazil and beyond. As Pedro Szasz, a consultant in São Paulo and one of the world’s top public transportation experts, puts it, ”Brazilians are good at soccer, samba, and bus systems.”

Other cities have taken notice. Committees from all corners of the globe descend on São Paulo every year to see how folks here run their buses ( ônibus , in Portuguese). São Paulo, after all, is hardly the only megacity facing megatraffic problems. Los Angeles, Mexico City, and Shanghai are but a few. The waste in time and fuel is enormous. According to the Texas Transportation Institute, in College Station, traffic congestion in 85 U.S. urban areas cost the nation more than US $63 billion in 2003. The International Association of Public Transport, in Brussels, puts such costs for 15 European countries at 120 billion per year.

How can we prevent cities from choking themselves in traffic and pollution? Experts all agree there’s no silver bullet. Cities need a mix of mass transit systems, and designing such systems needs to be part of a broader urban development plan. With its expansive bus operation, São Paulo is showing that this transportation option has a crucial role in that mix.

The concept of a modern, high-capacity bus system is often called bus rapid transit. BRT differs from conventional bus operations in that the coaches--often newer, more comfortable vehicles--run on dedicated portions of roadways, and stations feature off-vehicle fare collection and slightly elevated platforms to speed up boarding. Proponents say BRT systems have lower construction costs, can be built in a quarter to half the time subways require, and their operating costs are almost always covered by fare collection, eliminating the need for subsidies. BRT also offers more flexibility, because routes can be adjusted as the city grows, different bus types can be deployed, and cars can be allowed to use bus lanes during weekends.

Illustration: Bryan Christie Design

Now, there’s some debate about how many people BRT--or other systems, for that matter--can transport. One way transportation experts assess a system is by measuring its maximum throughput--much as a mechanical engineer would gauge the flow of water through a pipe. In that way, a single-lane BRT line is said to transport up to 15 000 passengers per hour in one direction, or nearly seven times as many as a freeway car lane. BRT’s capacity is similar to light rail’s but smaller than that of subway systems, some of which carry more than 50 000 passengers per hour. Although it would be nice if every metropolis had ample subway service, building such infrastructure is often beyond a city’s means. Whereas construction costs for a light-rail line can run anywhere from $15 million to $25 million per kilometer and subway systems from $50 million to $200 million, BRT systems require from less than $1 million to $20 million.

Not all bus corridors in São Paulo are full-featured BRT systems. Indeed, it’s hard to characterize all of this city’s different busways. You can find here nearly all the different configurations a transportation planner could concoct. Segregated corridors in the middle of avenues? A handful. Dedicated bus lanes on the left of roadways? Four, built not long ago. São Paulo is even constructing a 20-meter-high elevated busway that snakes its way above traffic--a controversial project whose original design called for all-electric, computer-controlled buses but which will go into operation using diesel coaches with drivers at the wheels. (One critic called it a ”drunken roller coaster that escaped from Playcenter [the local amusement park].”)

During the past decade, São Paulo reorganized its maze of bus lines into a more efficient network: structural lines with high-capacity coaches running mostly radially toward the city’s center, and local lines with nimbler microbuses connecting neighborhood streets to other bus lines and subway and train stations. São Paulo’s 11 bus corridors became a key piece in this reorganization. Its two most successful, the 14-km-long Santo Amaro–Nove de Julho corridor and the 33-km-long São Mateus–Jabaquara corridor, each transport more than 200 000 passengers per day.

”São Paulo is the biggest laboratory in the world in terms of transportation in many ways,” says Darío Hidalgo, a transportation specialist with the global management consultancy Booz Allen Hamilton, in Bogotá, Colombia. He says that bus experiments in São Paulo and in another Brazilian city--Curitiba, which began constructing a pioneer BRT system more than 30 years ago--helped inspire other cities to develop their own rapid bus projects. Bogotá, with nearly 7 million people, chaotic traffic, and not a single subway line, completed in 2000 what many consider to be an exemplary BRT project: the 80-km-plus TransMilenio system, which can move 40 000 people per hour per direction using two lanes. ”It’s a world record for buses,” says Hidalgo, who participated in the project.

Other cities that have built or are planning BRT systems include Boston, Cape Town, Chicago, Los Angeles, Mexico City, New Delhi, New York City, Ottawa, Paris, and Sydney. There are already 15 BRT systems operating in Asia--including those in Beijing, Jakarta, Nagoya, and Seoul--and 24 others soon to come. All these BRT systems may be very different in their design and operation, but they attempt to accomplish the same goals. One is getting people to use public transportation over private automobiles, thereby improving traffic and reducing tailpipe emissions. The other is providing a better way of getting around for those who don’t own cars. In most cities in the developing world, the carless are the majority of the population (70 percent in São Paulo, for example), so implementing an efficient bus system is also a matter of social equity.

How do planners in a megacity like São Paulo go about designing its transportation system? How do they know, say, where to build new busways?

Many of the answers come from a conference room--nicknamed the ”situation room”--at the headquarters of São Paulo’s metropolitan transportation agency. Indeed, improving transportation in São Paulo has been quite a war.

Use of public transportation had been declining for decades, but now for the first time its share is smaller than that of private transportation: 47 ­percent versus 53 percent, according to the last major ­government-­sponsored survey. With more cars on the street, driving has only gotten worse. Rush-hour backups throughout the city routinely add up to more than 100 km. And every three minutes, an additional automobile joins the fray. Lined up bumper-to-bumper, all of São Paulo’s 5.5 million cars would form a queue some 20 000 km long, enough to go halfway around the world. It’s probably a good thing people don’t start out at the same time.

After locking itself away in the ”situation room” for numerous meetings, a group of experts recently emerged with a major review of São Paulo’s transportation plans for the next 20 years. Pedro Benvenuto, who headed the review, says that the goal is to have transportation planning help reorganize the metropolis, especially by promoting the emergence of new job-dense areas outside the city’s center. While São Paulo has experienced the bulk of its population growth at the fringes of its metropolitan area, most jobs remained concentrated at central locations.

For the review, Benvenuto summoned transit officials, city planners, consultants, academics, and representatives from subway, rail, and bus companies. The work begins with the experts devising plans to increase access to public transportation, speed up existing services, build new infrastructure, and so on. Then it’s the modelers’ turn. This subgroup examines the proposed plans using an urban planning simulator called Tranus, an open-source program used by dozens of cities that’s like a kind of SimCity--the popular city-design game--minus the sleek graphics. The program simulates how transportation affects land use, and vice versa. To run it, the modelers feed in a digital representation of São Paulo’s roadways, a detailed map of the city’s real-estate characteristics, a database of daily trips for the entire population, and also social and economic indicators. Then they run dozens of simulations to assess the costs and benefits of different scenarios.

The group’s proposed review envisions an ideal 2025 city where public transportation ridership increases to about 60 ­percent, low-income people double the average number of daily trips they can afford, and even car drivers benefit, with average traffic speed increasing by 20 percent. The plan will require $20 billion in investments and calls for a significant expansion in all types of transportation infrastructure. Most resources will go into extending the subway network to 168 km from 60 km and the rail system to 372 km from 270 km. The bus system, which will continue to be the city’s largest people mover, is slated to receive an additional 366 km of dedicated lanes and 40 new transfer terminals. It’s an ambitious plan. But is it enough?

As any bus rider here will attest, there’s plenty of room for improvement. Many lines need better speed and consistency. Decrepit coaches ( latas velhas , or old cans, some would call them) need to be replaced. And some busways need more lanes and enhanced stations to keep long, slow-moving lines of coaches from bogging down the whole system. For experts like Pedro Szasz, São Paulo needs to be more ambitious with its bus projects. He says that, contrary to what detractors may claim, there is more than enough road space to take lanes for buses. The problem, he adds, is that large projects require the right political and economic conditions, and these are not easy to come by.

That’s not to say there hasn’t been progress. Riding on a bus in São Paulo, you might not notice all that’s required to keep things running efficiently. Consider fare collection. Called the bilhete único , or single ticket, it’s a wallet-size plastic card with a microchip inside. With technology from Philips, it stores how much money you’ve added and subtracts your current fare as you wave it near a card reader inside a bus. With the card, you can ride on up to four buses within two hours and pay only one fare. And you can use the same card on any bus--local, intercity, regional--as well as the subway or commuter rail.

The cards are not just convenient for passengers. Buses in the city are operated by a dozen private companies, which need to be paid according to the number of people they transport. The bus system’s revenues last year came to $1.65 billion. Before electronic fare collection was introduced, dividing the funds was a difficult task, with disputes over the figures (and also fraud) hard to avoid. Now, after completing its run, each bus transfers the fare data it has accumulated to an overseeing agency, which in turn distributes each company’s share.

”I’ve worked in the transportation sector for 30 years now, and this was always a dream,” says Frederico Bussinger, an electrical engineer turned transportation expert and the city’s ­secretary of transportation. ”That it’s all integrated now is no small accomplishment.”

And other advances are on their way. One is making buses more reliable. São Paulo is equipping all city buses with GPS systems. Each vehicle will carry a tracking device that continuously reports its location to a control center and also lets the driver communicate with remote supervisors. The monitoring will help make adjustments to operations and also provide information to users through displays at bus stops. Another advance is aesthetic. Previously, bus corridors required concrete and metal dividers that narrowed roadways and disfigured the urban landscape. Now a yellow stripe painted on the asphalt separates bus and car lanes, with digital cameras placed along the bus corridors. Invade one and you get a fine.

Photo: Julio Bittencourt


Engineers monitor all city  buses from a single control center.

”We are going from the bus of the Stone Age to the bus of the Information Age,” Benvenuto says.

Indeed, from the 1820s when horse-drawn carriages, called ”omnibuses,” hit the streets of Nantes, France, as the first urban public coaches, the bus has come a long way. According to one estimate, São Paulo’s modern diesel buses are 6.5 times more energy efficient than cars: buses consume an average of 2 ­kilowattâ''hours per passenger per trip, whereas cars require 13 kWh.

But of course, put too many buses together and you have a problem breathing. Automobiles here are the main culprits in urban air pollution, with buses adding less than 15 percent of the carbon monoxide and hydrocarbon pollutants in São Paulo’s air. But in or around a BRT corridor, the contribution from buses jumps to 50 percent. And concentration of particulate matter in busways can be twice as high as in regular roadways.

São Paulo, like other megacities with large vehicle fleets, has long been battling air pollution, which health officials estimate is responsible for 4000 premature deaths annually. The city’s bus agencies are replacing older buses with newer ones with better engine control systems and subjecting them to more stringent inspections. They also devised emission assessment metrics to grade each bus company’s fleet, which by contract needs to remain below a maximum level.

Also, there’s the possibility of benefiting from new vehicular technology. São Paulo has studied nearly all options--cleaner diesel, biodiesel, ethanol, natural gas, electricity, hybrids--but for the moment it is exploring a more ambitious proposition: buses powered by hydrogen fuel cells. Backed by the New York City–based United Nations Development Program and the Global Environment Facility, a funding agency in Washington, D.C., São Paulo embarked on a $16 million project to build five prototype buses and one hydrogen production and filling station.

”Five buses are not a lot, but it’s a beginning,” says Marcio Schettino, the project’s executive coordinator. ”We hope to both advance the technology and create a market for hydrogen-powered vehicles.”

The onboard fuel cell, developed by the Canadian company Ballard Power Systems, in Burnaby, B.C., combines hydrogen and oxygen to produce electricity, which powers a motor to propel the bus, with only water vapor as a by-­product. Another Canadian company, Hydrogenics, in Mississauga, Ont., will supply the equipment to produce 120 kilograms of hydrogen per day. The system as a whole will be zero-emission, because the hydrogen will be produced through electrolysis of water, and 90 percent of Brazil’s electricity comes from hydropower. Although the core technologies are imported, Brazilian companies will provide the buses’ chassis and bodies and Brazilian engineers will accompany all stages of the development.

One of the advantages of the Brazilian bus in comparison to others tested in Europe and North America is that it will be a hybrid, recovering energy during braking by turning the motor into a generator and charging a battery. The 90â''­passenger buses will have a range of 300 km, which is about the same as the diesel buses currently used here. Monitored by GPS, the vehicles will be tested for four years running for about 1 million km on the São Mateus–Jabaquara busway, in the southeastern part of the city.

To be sure, air pollution and congestion are hardly new challenges for megacities like São Paulo. However, the problems seem only to be getting worse. A new major government-backed transportation survey will be conducted this year, and experts will spend months scrutinizing the new data. Whether bus systems will help clear the air and streets remains to be seen, but one thing is certain: São Paulo has plenty of lessons for other mega­cities with transportation problems of their own.

It's 8:00 p.m. and Carlos Soares gets off the bus at the Anhangabaú stop. The ride from his workplace took 55 minutes, but Soares is not quite home yet. From here, he’s getting on the subway, and after a short ride he still has a local bus to take--a 2â''hour journey that is typical for millions here. Still, Soares is not complaining. He says that after the Rebouças bus corridor began operation, it cut his daily commute by half an hour each way. And while riding, he’s able to talk on the cellphone, read a book, or chat with a reporter. Much better than grinding his teeth in stop-and-go traffic.

”The [bus] corridor is great,” he says. ”I just wish it went all the way to my door.”

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