  COVID-19 introduced tremendous disruptions to the normal operation of transit
agencies, led to a massive suspension of regular service, and disturbed the
access to essential mobility for many transit-dependent populations. In this
study, we reexamine the national-level service disruption of the public
transportation system as a result of the COVID-19 pandemic and investigate the
disparities in the reduction of transit supply, causing certain racial-ethnic
groups to be disproportionately affected. To support our analysis, we collect
GTFS data from 232 transit agencies covering over 89 million people across 45
states in the U.S. Our findings suggest more disadvantaged communities and
certain racial-ethnic groups have experienced disproportional reductions in
transit supply, regardless of their pre-pandemic level of service. Further, we
employ causal mediation analyses to address the mediation effect of the
pre-pandemic level of transit service on the relationship between
race/ethnicity and transit supply reduction. This analysis validates the
disproportionate reduction in service quality for specific racial/ethnic
groups, a trend evident across the majority of transit agencies. In particular,
Black Americans are found to be associated with the greatest absolute service
loss and also the largest total effects on transit supply reductions, while the
White and Asian groups are less impacted. We further report that the most
impacted communities by transit loss mainly consist of minority populations,
where the reductions in transit are correlated with pandemic-related health and
economic burdens and result in greater changes in mobility intensity. Our study
contributes to a comprehensive understanding of transit inequities due to the
pandemic and provides valuable insights to better prepare public transportation
systems against future nationwide disasters.
