Insurgentes, the jampacked boulevard Mexico City's 18 million residents love to hate, cuts through this massive metropolis, north to south, filled with cars spewing smoke, taxis swinging illegal U-turns, and rickety commuter minivans screeching to stops with no discernible rhyme or reason.
Confusion, delays, and a feeling of being fumigated has, for as long as most people here can remember, been about as sure a thing here as traditional Posada processions at Christmastime.
Until this week, that is, thanks to popular mayor and presidential hopeful Andrés Manuel López Obrador's latest addition to the city: the Metrobus, chugging along this summer on a stretch of Insurgentes near you. It looks like a regular bus and moves like a regular bus - but here in Mexico City it is being hailed as nothing short of a revolution.
Over the past few months Insurgentes has been reengineered (including cutting down thousands of trees, much to the shock of environmentalists) to create designated Metrobus lanes running down its center. Commuters - of whom there are an estimated quarter of a million daily - board the Metrobuses from the middle of the avenue, at one of the 36 modern stations. A fleet of 90 low-pollution Volvo buses, with official capacity for 160 passengers each, has been introduced, replacing over 300 aging and smaller municipal and private buses and vans.
"You change an old, atomized system with no regulation and no control over the number of buses and drivers to something organized, with new buses and good lanes and you have a success on your hands," says Bernardo Baranda, a researcher at Mexico City's Center of Sustainable Transport, a private group that advised the government on the project.
Mr. Baranda estimates the new system will shave an hour off the nearly two hours it takes riders to travel the 12-mile route at rush hour and help reduce pollution by enticing more people to use public transportation. His organization says Mexico City has about 3.5 million registered cars, and that number has been growing by an average of almost 10 percent a year for a decade.
Modeled after similar so-called "bus rapid transit" (BRT) systems in Brazil and Colombia, the idea is to build some of the best qualities of a subway line - designated lanes, spacious passenger loading areas, prepaid electronic ticketing, and buses with lots of doors to get passengers on and off quickly - into a much less expensive bus system. While other parts of the capital already have an underground - and a good one at that - building a new one along Insurgentes might have broken the bank: The Metrobus cost a total of $30 million, as opposed to as much as $130 million per mile for a subway.
The service, free this month, leading to longer waits and crowded carriages during its trial period, will eventually cost 3.5 pesos, or about 40 cents a ride.
"It is a devilishly difficult business to build an effective transportation system in any crowded city - whether rich or poor," says Hal Harvey, environment program director at the Hewlett Foundation, a charitable group based in Menlo Park, Calif. "Subways are too expensive to reach more than a few lines. Relying on cars or conventional buses condemns citizens to endless traffic jams and exhaust fumes. BRT offers the one way out."
Wenceslao Garcia Olivera is a policeman who used to have a street beat in the nearby San Angel neighborhood. Starting this week, however, his posting is at the Metrobus station on Altavista and Insurgentes. His mission: to ensure passengers waiting for the vehicles don't stick their hands or heads too far out into the street and get hit by one. "What people don't understand is that this is something completely different," he says. "It's a subway in clever disguise."
Mr. Garcia admits, however, that he still rides a microbus to work; the Metrobus does not go in his direction, and, he says, lowering his voice, he would not want to wait so long or fight the crowds. "I suppose there is room for further improvement," he confides.
The scarcity of routes, waits as long as 15 minutes between buses, and crowds are not the only complaints heard about the Metrobus. Critics fear the whole program could backfire, with buses taking up lanes previously used for cars, forcing them to look for shortcuts through previously quieter neighborhoods.
So far, in its first few days of operation, there have been a half dozen small accidents, mainly because of cars, unaccustomed to the designated lanes, driving right into the buses; and pedestrians, unaccustomed to crossing busy Insurgents to catch their buses, walking into cars. But, says traffic policeman Jose Antonio Reyes Duran, taking a break from a few hours of nonstop whistle-blowing, he expects it all to get clearer within a few weeks.
"These days we just give out warnings, because no one yet knows what is going on," he says. "But soon we are going to get serious and give out fines.... People have to understand this is the future." Like it or not, he says, "Insurgentes is a different place nowadays."
• Ms. Harman is Latin America bureau chief for the Monitor and USA Today. Additional reporting by Eloise Quintanilla.