Mexico City’s air quality is said to be the worst in the Western Hemisphere to the point that, in the past decades, birds would even fall from the sky already dead. Locals, on the other hand, described that living in the city was comparable to smoking two cigarette packs daily.
This growing concern prompted the city to undertake measures in improving the air quality, which include driving restrictions one or two days in the weekdays, first initiated in 1989. Then in 2008, it implemented additional driving restrictions every Saturday.
Such restrictions, however, have small results, according to a study published in Scientific Reports.
“Saturday driving restrictions are a flawed policy. It’s a big hassle for people and does not improve air quality,” Lucas W. Davis, associate professor at the Haas School of Business in University of California Berkeley and faculty director at the Energy Institute in Haas, said in a statement.
As the first study to investigate the effects of driving restrictions on Saturdays in the city, it made a comparison of the levels of pollution of eight primary pollutants or toxins before and after said program took effect.
Supporters of the program estimated that there would be a reduction of vehicle emissions by 15% or even more. But even with lesser motorists on Saturdays, the program had “close to zero impact,” the study said.
Wanting to establish the impact of weekend driving restrictions, Davis made an analysis of the hourly data on air pollution in 29 monitoring stations across Mexico City from the period of 2005 to 2012.
None of the pollutants he identified lessened as a result of the Saturday restriction.
Wondering why it failed to minimize the pollution, he subsequently studied ridership data from the public transportation systems of the city—from buses to railways—and discovered no visible increase with the riders on Saturday.
“People have found other ways to get around the driving restrictions,” said Davis. “Some purchase multiple cars, others take taxis or Uber.”
He argued that, with Uber and similar taxi services increasingly becoming rampant, the policies on driving restrictions will remain to struggle in improving the quality of air. He instead suggested that the city and other similarly populated cities should require more stiff and strict vehicle emission tests.
“Test every car, test every year. If you have a car that’s polluting the air, you can’t drive it. Period,” he said.
The research, Saturday Driving Restrictions Fail to Improve Air Quality in Mexico City, revealed that Mexico City has particulate levels three to four times higher than in Buenos Aires, Sao Paulo, Los Angeles, and New York.
(Photo Credit: University of California Berkeley)