Reducing vehicle miles traveled (VMT) would generate many benefits, including alleviating traffic congestion, reducing air pollution, reducing greenhouse gas (GHG) emissions, reducing our dependence on foreign oil, improving public health through increased exercise, and enhancing interactions within our communities. There are plenty of policy ideas for how to reduce VMT and GHG emissions from passenger vehicles. Road and parking pricing, mixed use zoning, investments in alternative modes, and household travel planning programs represent just a small sample of the possibilities. However, these policies can be costly, they may require substantial political capital, and/or they may have an effect only over the long-run. For planners and local government officials aiming to affect VMT to choose wisely, it is necessary to know – in addition to its cost, likelihood of political acceptance, and any co-benefits – how much each policy option will actually affect VMT and GHG emissions.
This white paper is written to be a practitioner’s guide to the extensive academic literature that provides evidence of policy effectiveness in reducing VMT. It identifies theoretical relationships between land use planning, transport system investments and services, and VMT, highlights the challenges inherent in exploring these relationships using real-world data, and discusses three prominent studies in detail with respect to these challenges. The paper concludes with a discussion of how results from this literature can be practically applied to inform policy and planning decisions.