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TDM and sustainable mobility matter more than ever - WTS Greater New York Chapter

Author: Heliana Verónica Higbie

Sustainability has been defined as “development that meets the needs of the present without compromising the ability of future generations to meet their own needs.” As the concept of sustainability percolates through our complex global society, transportation professionals are beginning to see its importance and are redefining goals and strategies through the lens of sustainability.

A key development in this area has been a focus on Transportation Demand Management (TDM) and sustainable mobility. TDM maximizes travelers’ choices by promoting strategies that encourage a behavioral shift away from single-occupant vehicle (SOV) trips and toward non-SOV transportation modes. In other words, TDM means encouraging and enabling people to carpool, vanpool, walk, bike, take mass transit or telework.

Negative impacts of climate change on human survival have gone from a distant possibility to present-day reality. 2020 was the hottest year on record, and 2021 has already seen record-breaking wildfires, droughts, tornadoes and hurricanes, and flash flooding in New York City for the first time in recorded history. These are the results of a steady increase in the average global temperature.

Reducing Greenhouse Gas (GHG) emissions has been identified as critical to avoiding the worst-case scenarios of climate change. Historically, climate impacts tend to be greater for traditionally underserved and disadvantaged populations. Therefore, it is essential to prioritize mobility equity, in order to simultaneously increase access and mobility options, while reducing air pollution and improving quality of life for low-income and vulnerable populations.

According to the Environmental Protection Agency (EPA), the transportation sector accounts for nearly one-third of total U.S. Green House Gas (GHG) emissions. Over the last 40 years, there has been an increase in the rate of commuting where one person travels alone in a passenger car—the SOV problem. Light-duty vehicles account for a whopping 59% of GHG emissions from the transportation sector, and they have been wisely targeted for reducing GHG emissions.

TDM strategies have become an essential tool in maximizing the use of existing public transit infrastructure and mobility modes to reduce SOV reliance. Effective TDM strategies require transportation professionals to understand how people make their transportation decisions and then incentivize them to make more sustainable transportation choices. Partnerships such as the one formed between WTS and ACT are necessary to the interdisciplinary nature of TDM solutions. Great strides have been made in conceiving and implementing TDM strategies that are effective at shifting individual behavior away from SOV commuting toward rideshares, walking, biking, taking public transit, or teleworking.

The COVID-19 pandemic dealt sustainable transportation efforts a major setback. A recent study from IBM found that as life returns to normal people have flocked to personal vehicles rather than returning to public transportation. The study shows that more than 20% of people who regularly used buses, subways, or trains now said they no longer would. And another 28% said they will likely use public transportation less often. Solving this problem will require more transportation professionals to be actively focused on finding TDM strategies. A bright side of the pandemic has been positive behavior change, which encouraged people to telework, bike, and walk more than they used to do before 2020.


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