Assessing Transportation Impacts Using Vehicle Miles Traveled Rather Than Level of Service Can Incentivize Infill Development

Local governments have long relied on Level of Service (LOS), a measure of automobile congestion, as the basis for assessing transportation impacts of land use development projects. However, use of the LOS metric creates an incentive for projects that contribute to urban sprawl while penalizing denser development projects that could allow people better accessibility to jobs and services through alternate modes like walking, bicycling, or transit. Starting July 1, 2020, local governments in California are required to use vehicle miles traveled (VMT) rather than LOS to measure land use projects’ transportation impacts. Researchers at UC Davis studied how this change affects the approval process for urban development. Because most agencies have not yet switched to using VMT in their analyses, the researchers looked back at environmental documents for development projects in the City of Los Angeles between 2001 and 2016 and determined whether these projects could have benefited from using a VMT metric instead of LOS for measuring their transportation impacts. Findings are summarized in this policy brief.