The metric by which transportation impacts are analyzed under the California Environmental Quality Act (“CEQA”) has changed, and real estate developers are quickly realizing that it is affecting the economic bottom line of their properties. Whether a proposed project has a significant environmental impact will no longer be determined by analyzing traffic congestion and counting vehicle trips. Instead, pursuant to Section 15064.3 of the CEQA Guidelines and the Governor’s Office of Planning and Research, transportation impacts will be determined by measuring the vehicle miles traveled by occupants (“VMT”) in any proposed project. Because VMT can be stated in “absolute terms, per capita, per household,” the expectation is that VMT will lead to more varied analysis. The stated rationale for the change is to further align VMT with California’s greenhouse emission goals because it accounts for emissions and traffic as a result of additional miles traveled.
What Is VMT and How Is VMT Measured?
VMT is, generally, the measure of distance of automobile travel by occupants moving to, from, and within a project. The traditional guidepost of automobile delay will no longer factor into the environmental impact analysis. Generally, projects close to public transit have fewer vehicle miles traveled and transportation impacts. Indeed, projects within a half a mile of a major transit stop or a stop along a high-quality transit corridor are presumed to cause less than a significant impact under the CEQA Guidelines and advisory guidelines.
Measuring the total miles traveled by vehicles as a result of a project requires careful modeling. The best method for assessing VMT for residential and mixed-use projects is the tour-and-trip based approach. For this approach, VMT is measured by analyzing the miles a person in a new project will travel to get to routine, necessary places, such as work and the grocery store.
How Do You Mitigate VMT?
If a proposed project generates sufficient VMT so that there is a “significant environmental impact,” then the VMT must be mitigated to a level of insignificance. VMT is mitigated by reducing the total number of miles traveled by automobiles. This can be accomplished by utilizing a variety of tactics, including:
What Are the Costs of Mitigation?
- Improving or increasing access to transit
- Increasing access to common goods and services
- Incorporating affordable housing
- Providing incentives or subsidies that increase the use of transit modes other than a single occupancy vehicle
- Providing telework options
- Providing transit passes
- Implementing or providing access to a commute reduction program
The costs of mitigation in urban settings will be less significant due to increased density, access to common goods and services, and availability of transportation infrastructure. The costs of mitigation outside of urban settings is more difficult to forecast. VMT will likely have a significant impact on new residential developments in suburban and rural areas. Outside of urban settings, some estimate that VMT mitigation could increase the cost of a project up to $80,000 per residence. In order to control costs, developers should foresee and incorporate VMT mitigation measures at the design phase.
Although VMT is the measure of transportation impact for CEQA purposes, lead agencies may still use the traditional “level of service” analysis for evaluation of a project’s compliance with a general plan. This means that residential developers may need to conduct both VMT and “level of service” studies, increasing the costs of seeking entitlements and the cost of mitigation measures for general plan compliance.