noise on physical and mental health are inequitably distributed and, except near airports and segments of urban Interstates, have been largely unaddressed. Fortunately, noise levels will also decline with the transition to electric drive. Transportation barriers to health care disproportinately harm low-income people and require further innovation in access to services. Active transportation can improve public health, but jurisdictions need greater data-driven guidance on designs and policies that are safe, convenient, and likely to shift behavior to cycling and walking.

priorities. In most cases, government priorities have been to improve roads or transit service, not access to or affordability of vehicles. In addition, environmental justice efforts during project selection and design are too often approached as procedural requirements instead of being weighed as important inputs along with all other considerations.

People of color living in racially segregated communities and on reservations often face disproportionately high constraints in accessing transportation, including significant cost burdens.^{110,111,112,113,114} As a result, these communities are disproportionately likely to lack access to employment, health care, education, healthy food, and other life needs and opportunities. Transportation’s importance for providing access to opportunities is a well-studied area, especially for access to work, but also for access to quality education and health care, and access to a reliable vehicle remains one of the largest determinants of an individual or household’s access to opportunities.^115,116,117 While this research indicates that shortcomings in transportation are seldom the sole cause of poor access, studies also suggest that improvements in transportation, including increased access to private vehicles, can play a meaningful role in helping to address these problems.^118,119,120 This access may come via increased vehicle ownership, programs to reduce insurance and maintenance costs, availability of car-share and car rental services, or other opportunities tailored to particular places. More research to understand and document how transportation affects all individuals’ access to opportunities, particularly for people of color, is essential for designing and implementing ameliorating policies.

Individuals have sometimes pointed to patterns of decision making indicative of racial and gender bias when criticizing transportation planning and investment priorities, particularly in urban areas. Examples, as noted above, include the siting of urban freeways in low-income—and often racially segregated—neighborhoods, creating dislocation, isolation, and exposure to negative environmental factors such as noise, poor air quality, and safety hazards.¹²¹ Such choices are seldom made by state and local transportation agencies alone,¹²² but planning and implementation have, in fact, largely been the responsibility of these institutions.^123,124 Curbing racism in decision-making processes and power structures across all levels of government is essential to equitable transportation planning and investment choices. Understanding racial bias in transportation institutions and better involving low-income people and people of color in planning for their communities’ transportation is a critical step toward ensuring access for all.

Although it had been known for decades that transportation plans and policies had disparate effects on communities of color and low-income populations,¹²⁵ the civil rights implications of emphasizing urban

highways through low-income and minority areas were not addressed in transportation legislation until the 1990s.¹²⁶ More laws, policies, standard practices, and regulations are in place today to prevent and remedy such inequities. Examples range from commitments to appoint public transit boards that are more demographically representative of communities of color¹²⁷ to ensuring that road pricing schemes are not disproportionately burdensome to low-income populations. Because long-range regional transportation and land use planning can be so critical to efforts to address past and minimize future inequities, these areas will be useful research focus points for equity-relevant data, metrics, and analytic tools.¹²⁸ Existing data and methods for measuring equity in transportation-related projects are inconsistent across jurisdictions and often incomplete; recent efforts to improve these measures include shifts away from measuring mobility (measures such as number of trips and numbers of miles traveled) to measuring accessibility and outcomes.^129,130 The interactions among the many dimensions of equity concerns, including race and income among others, are complex and difficult to distill into concise terms that allow advocates and policy makers to communicate clearly.

Transportation networks, and especially links between employment centers and residential areas, are inextricably tied to land use. The built environment, whether in areas that are sparse and rural or dense and urban, is an important factor in equity analyses. As described in more detail in the Land Use section of this publication, zoning and housing decisions in the United States have often resulted in policies that discriminate against lower-income households and people of color, often requiring them to live or move to places less convenient to city centers or to high-quality schools and jobs. Myriad projects are under way to improve accessibility for late-night activity and in areas where transit service is infrequent through innovative transit, microtransit, and shared mobility options; examples include Dallas Area Rapid Transit’s GoLink,¹³¹ Los Angeles’s Metro Micro,¹³² and Austin’s Capital Metro Pickup.¹³³ Programs to improve automobile access through auto ownership financing programs, efforts to offset the many ongoing (and often inequitable¹³⁴) costs of driving, and policies to broaden access to driver licensing also exist.¹³⁵ The IRA and the IIJA also include policies intended to increase access to used electric vehicles through tax credits for vehicle purchase, and targeted funding for charging infrastructure in low-income areas. The California Air Resources Board provides additional assistance to low-income households to purchase zero-emissions vehicles.¹³⁶ The effectiveness, including cost-effectiveness, of these many programs in filling mobility gaps remains an important area for further research.

Reducing transportation-related inequities requires reaching agreement on the means of defining, measuring, and addressing the