Impact of Transit on Mobility, Equity, and Economy in the Chicago Metropolitan Region

Omer Verbas; Taner Cokyasar; Seamus Joyce-Johnson; Scott Wainwright; Maeve Coates; Aymeric Rousseau; Jim Aloisi; Anson Stewart; Joshua Auld

arXiv · 2409.04568

Impact of Transit on Mobility, Equity, and Economy in the Chicago Metropolitan Region

Omer Verbas·Taner Cokyasar·Seamus Joyce-Johnson·Scott Wainwright·Maeve Coates·Aymeric Rousseau·Jim Aloisi·Anson Stewart·Joshua Auld

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Abstract

Transit is essential for urban transportation and achieving net-zero targets. In urban areas like the Chicago Metropolitan Region, transit enhances mobility and connects people, fostering a dynamic economy. To quantify the mobility and selected economic impacts of transit, we use a novel agent-based simulation model POLARIS to compare baseline service against a scenario in which transit is completely removed. The transit-removal scenario assumes higher car ownership and results in higher traffic congestion, numerous activity cancellations, and economic decline. In this scenario, average travel times increase by 14.2% regionally and 34.7% within the City of Chicago. The resulting congestion causes significant activity cancellations despite increased car ownership: 11.8% of non-work and 2.8% of work/school activities regionally, totaling an 8.6% overall cancellation rate. In the city, non-work cancellations would reach 26.9%, and work/school cancellations 7.3%, leading to a 19.9% overall cancellation rate. The impact varies between groups. Women and lower-income individuals are more likely to cancel activities than men and higher-income groups. Women account for 53.7% of non-work and 53.0% of total cancellations. The lowest 40% income group experiences 50.2% of non-work and 48.0% of overall cancellations. Combined, activity cancellations, travel time losses, and increased car ownership cost the region $35.4 billion. With annual public transit funding at $2.7 billion, the ratio is 13 to 1, underscoring transit's critical role in mobility, equity, and economic health.

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Omer Verbas, Taner Cokyasar, Seamus Joyce-Johnson, Scott Wainwright, Maeve Coates, Aymeric Rousseau, Jim Aloisi, Anson Stewart, Joshua Auld. 2024-09-06. Impact of Transit on Mobility, Equity, and Economy in the Chicago Metropolitan Region. https://arxiv.org/abs/2409.04568

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