Study on GHG emissions avoided from public transit

According to a study on GHGs avoided from public transit, each ton of CO2 emitted by the STM serves to avoid another 20 in Montréal.

Together, several municipal and provincial partners worked with public transit companies on a study to quantify GHGs avoided from public transit in the Greater Montréal area. One of its goals was to identify a known, reliable methodology that would make it possible to compare results obtained by Montréal with those of other major cities in North America.

GHG emissions avoided from public transit were quantified according to three major categories:

  1. The impact of reduced car use
  2. The impact of less traffic congestion
  3. The impact of urban densification

These three categories were measured on the basis of the geographical boundaries of the Montréal metropolitan community (CMM). The approaches used to calculate the amount of avoided GHGs are consistent with the methodologies recommended by the American Public Transportation Association (APTA) and the Transit Cooperative Research Program (TCRP).

The results obtained show total avoided GHG emissions of 3,911,000 t CO2 eq per year which, for purposes of comparison, represent about 55% of overall emissions caused by road transportation in the CMM’s territory. Those results also confirm the significant impact of public transit on reducing GHG emissions within CMM’s territory, but also throughout Québec.

In 2015, the STM emitted a total of 158,000 tons of CO2. The study shows that each ton of CO2 emitted by the STM serves to avoid another 20 tons in Montréal.

Public transit users help reduce not only GHG emissions, but other air pollutants as well, thereby helping to improve air quality and public health.  

Étude sur les GES évités par le transport collectif (French only)

Top of page