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Improving air quality in the Valley of Mexico is urgent and represents an enormous challenge for society



 February 2016


 The monumental challenge

The mobility and air quality crisis in Mexico City’s Metropolitan Area (ZMVM) requires structural changes and implementation of very drastic measures, even if they are unpopular among the population. These measures should be directed at giving priority to public transportation and significantly restricting the use of private vehicles, and should be commensurable to environmental and public health costs for society caused by pollution and congestion. The social cost per car may even exceed its market value, although currently it is fully subsidized in most large cities, including the ZMVM. However, there are success stories, such as Tokyo and Singapore, where the retail price of a car reflects the actual cost it has for society, and may reach more than twice its market value.

The profound transformation required by the city must be accompanied by development policies aimed at containing the expansion of the urban sprawl and rescuing public space, including the creation of green areas.

It is evident that such measures cannot be implemented in the short term, since they require large investments in public transportation infrastructure as well as raising awareness among society about the benefits these generate. Continuing with inertial measures may cause a considerable deterioration of the current situation, and the end result may be the existing reality lived in cities such as Manila and Lagos, Nigeria, where daily average commuting times are even higher than in Mexico City, which often exceeds two hours per commute.

The situation in the Valley of Mexico

Recently, there has been a broad debate on the reasons why established pollution limits set by the Mexican Official Regulations have been exceeded in the ZMVM.

In the Valley of Mexico, the air pollution problem is complex; it is due to a combination of multiple causes, and there are no single measures or “magical solutions” to solve it. Among other factors, its geographical location and orographic characteristics have a decisive role on air quality, as it is located in a closed basin, with an average altitude of 2,240 meters above sea level, surrounded by a mountain range. These natural conditions make it difficult for wind circulation and dispersion of pollutants.

The governments of Mexico City and the State of Mexico have jointly implemented for more than 30 years, programs to control emissions of air pollutants and improve air quality. Such efforts have yielded positive results. However, atmospheric concentrations of ozone and particulate matter persistently exceed the limits set by Mexican Regulations, and in the case of ozone, have as well increased from 2011 to date.

 Currently, the ZMVM has the highest levels of ozone pollution nationwide, and is the fourth city in terms of fine particle presence, the most worrisome contaminant from a public health point of view. Scientific evidence indicates that there is a correlation between exposure to air pollution and the incidence of respiratory and cardiovascular disease, which can cause premature deaths in vulnerable segments of the population and poor lung development in infants. As a result of these health impacts, there are serious economic and social repercussions for the country.

 Origin of the air quality problem

The source contributing most to pollution in the ZMVM is transport; private cars generate most of ozone precursors and are the second largest source of emissions of fine particles, only after heavy diesel transportation. The Valley of Mexico has a fleet of nearly 5 million vehicles, which has grown in the last decade at an average annual rate of 3.8%. This growth is explained, among other reasons, by the irrational expansion of the urban sprawl, an inadequate and poor public transportation system, and a mobility model that privileges and subsidizes private transportation. The growing traffic congestion is a factor that weighs more and more on poor air quality in the Valley of Mexico. It also generates a significant deterioration in the quality of life and productivity of its citizens, and reduces the competitiveness of the city.

Coupled with growing congestion, the average age of the fleet exceeds twelve years of age. This is relevant because, given the accelerated rate of technological advances, most recent vehicle models with cutting edge equipment and controls, generate less emissions every time. A vehicle over 20 years, can contaminate up to 20 times more than one with the latest technology, regardless of its maintenance. This differentiation between emissions from new cars against old is valid in general, although it doesn’t always apply in Mexico, as there are in the market, recent model vehicles with obsolete and highly polluting technologies, which are sold to access segments of the middle income population.

 New rules for vehicular pollution verification

The recent decision to adjust the Vehicular Pollution Verification Program, providing holograms based only on emission levels, not the vehicle year, aggravated traffic congestion. In addition to this modification to the Program, there are a large number of vehicles circulating in the ZMVM that had their license plates processed in other states. This is due to various reasons, including avoiding ownership taxes, and having access to a hologram even without having the need to take the vehicle to a verification center.

In the last six months we’ve seen an increase of hundreds of thousands of vehicles circulating daily. In many cases, moreover, they’re vehicles with high emission levels which gained access to a daily circulation hologram taking advantage of corrupt practices and obvious flaws of verification systems. According to an analysis made by the Mario Molina Center from measurements made in 2015 with remote sensor equipment, about 45% of vehicles circulating with hologram zero and 80% of vehicles with a hologram two (circulating restrictions, two times a week) surpass the limits allowed by current regulations. This is in itself serious, but even more so when you consider that these limits are too lax and should be updated.

 New Traffic Regulations

In the recent debate, it has been argued that some of the provisions of Mexico City’s new Traffic Regulations, particularly the more restrictive speed limits, have negative effects on air quality. From our point of view, the Traffic Regulations, whose express purpose is to reduce road accidents, it is not a matter requiring priority attention from an air pollution perspective. While there is a correlation between speed and emissions, which varies according to the pollutant in question, generally optimal emissions and fuel consumption occurs at speeds between 55 and 85 kilometers per hour, especially if constant acceleration is kept. Unfortunately, in Mexico City, regardless of the limits, the average speed during peak hours is between 8 and 11 kilometers per hour, as a result of traffic congestion.

 Solutions and most relevant measures

We must focus on public policy actions which are urgent to discuss and implement, and that require the concerted work between different levels of government, academia, private sector, civil society organizations and the general population. We must also ensure that a greater social welfare is achieved, as in cities like Tokyo and Singapore. This requires a considerable effort of communication and awareness among society.

From our perspective, the most relevant measures include:

Considerably expanding and improving the quality, safety and reliability of public transportation, ensuring access to the most vulnerable economic segments of the population.

  1. Designing and implementing policies restricting the use of private transportation by eliminating the implicit subsidy which it has, by establishing, for example, a tax or ownership fee associated with the vehicle’s value and its emissions; fuel prices that reflect environmental and health impacts; rates and space limits for parking lots as well as congestion charges.
  2. Regulating inter and intra-freight transportation in regards to weights and dimensions allowed, routes and times of access and circulation, and mechanical physical inspection processes and verification of emissions.
  3. Promoting territorial development policies to contain the expansion of the urban sprawl, encouraging densification, mixed land uses and rescuing public spaces and green areas.
  4. Tackling corruption and ensuring that vehicle emissions testing centers comply with current regulations and update the maximum allowable limits of pollutant emissions and fuel quality content in the Mexican Official Regulations.
  5. Encouraging the penetration of cleaner and more efficient vehicle technologies, such as electric and hybrid cars, buses and trucks.

While these measures may require substantial investment, the benefits for society by far outweigh its cost.

We reiterate our willingness to cooperate in achieving actions aimed at solving the problem of air quality in the Valley of Mexico.

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