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Mass Transit

An eastbound Metropolitan Area Express light rail train stops at Yamhill Street and 2nd Avenue in downtown Portland, Oregon. With 97 stations, ridership on the MAX is approximately 120,000 people per week.

Curitiba, Brazil, developed the first bus rapid transit (BRT) system in the 1970s, a model replicated in more than 200 cities worldwide. Dedicated BRT lanes along main thoroughfares—separate corridors from automobiles—were installed for fifty times less than the cost of rail. Bus stops were designed to be more like metro stations with multiple points of entry and exit.

All mass transit modes use scale to their emissions advantage. When someone opts to ride a streetcar, bus, or subway rather than driving a car or hailing a cab, greenhouse gases are averted.

The benefits go beyond emissions reduction and accrue to all city dwellers, not just those who use mass transit. By reducing the volume of cars, mass transit relieves traffic congestion. With fewer people driving, fewer accidents and fatalities take place. Overall, air pollution drops. Mass transit also makes cities more equitable by providing mobility to those who cannot drive.

Urban transport is the single largest source of transportation-related emissions, and growing. With good urban design, mass transit can help embed mobility, livability, and sustainability in cities.


Curitiba, Brazil…Jaime Lerner: Adler, David. “Story of Cities #37: How Radical Ideas Turned Curitiba into Brazil’s ‘Green Capital.’” The Guardian, May 6, 2016.

dedicated lanes…installation costs [vs.] rail: Reed, Drew. “How Curitiba’s BRT Stations Sparked a Transport Revolution.” The Guardian. May 26, 2015.

Curitiba’s…passengers [vs.] London’s Tube: Adler, “Green Capital.”

bus rapid transit…replicated…worldwide: Global BRT Data.

transport sector…emissions: Sims R., R. Schaeffer, F. Creutzig, X. Cruz-Núñez, M. D’Agosto, D. Dimitriu, M.J. Figueroa Meza, L. Fulton, S. Kobayashi, O. Lah, A. McKinnon, P. Newman, M. Ouyang, J.J. Schauer, D. Sperling, and G. Tiwari. “Transport.” In Climate Change 2014: Mitigation of Climate Change. Contribution of Working Group III to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change. Cambridge, UK, and New York: Cambridge University Press, 2014.

Urban transport…use of cars: Pyper, Julia. “Cars Will Cook the Planet Absent Shift to Public Transportation.” Scientific American. September 17, 2014.

United States…daily commuters: Cox, Wendell. “Evaluating Urban Rail.” December 5, 2014.

[vs.] Singapore and London: UN-HABITAT. Planning and Design for Sustainable Urban Mobility: Global Report on Human Settlements 2013. United Nations Human Settlements Programme, 2013.

fewer accidents and fatalities: Pourbaix, J. “Towards a Smart Future for Cities: Urban Transport Scenarios for 2025.” Public Transport International, 60, no. 3 (2011): 8-10.

transit…makes cities more equitable: Zhao, X., A. Mahendra, N. Godfrey,,H. Dalkmann, P. Rode, and G. Floater. Unlocking the Power of Urban Transit Systems for Better Growth and a Better Climate. London and Washington, D.C.: New Climate Economy, 2015.

“A train is a small society”: Gopnik, Adam. “The Plot Against Trains.” The New Yorker. May 15, 2015.

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