ALIGN: Frequently Asked Questions

What is Level of Service?
Level of service (LOS) measures vehicle delay at intersections and on roadways and is represented as a letter grade A through F. LOS A represents free-flowing traffic, while LOS F represents congested conditions. In order to calculate the level of service for a development project, a multi-step process is required that must identify, estimate or obtain the following information: potentially affected intersections (i.e., study intersections); traffic counts at study intersections; the number of trips generated by the project, split between employees and non-employees; the assignment of the trips to particular modes of transportation (e.g., auto, transit, bicycling, walking); for vehicle trips, the number of passengers in a vehicle; the distribution of the trips on the transportation network; and the direction in which the trips are headed.  With this information, traffic simulation software estimates vehicle delay at the study intersections with and without the project.

In San Francisco, we currently use level of service as an environmental analysis tool as well as a planning tool.  LOS is used to measure potential transportation impacts of projects subject to CEQA, including development projects, transportation projects, and long-range plans. In general, a project that was estimated to change LOS at an individual intersection to one of the bottom two rankings (D and F) triggered significant impacts under CEQA in San Francisco.  If a project triggers a significant impact under CEQA, it requires mitigation measures and a higher level of environmental review. In San Francisco, it was rare for projects to require a higher level of environmental review solely because of LOS significant impacts.

What is Vehicle Miles Traveled?
Vehicle miles traveled per person (or per capita) is a measurement of the amount and distance that a resident, employee, or visitor drives, accounting for the number of passengers within a vehicle. Many interdependent factors affect the amount and distance a person might drive. In particular, the built environment affects how many places a person can access within a given distance, time, and cost, using different ways of travels (e.g., private vehicle, public transit, bicycling, walking, etc.). Typically, low-density development located at great distances from other land uses and in areas with few options for ways of travel provides less access than a location with high density, mix of land uses, and numerous ways of travel. Therefore, low-density development typically generates more VMT compared to development located in urban areas. The information required to calculate VMT was already required in order to calculate LOS impacts and emissions of air quality and greenhouse gases.

Why is vehicle miles traveled better than level of service for measuring environmental effects?
The issues associated with LOS analysis and environmental review have been known for several years.  A common concern regarding LOS is that it’s inconsistent with other state and local laws for protecting the environment because it is biased against smart growth – infill development near transit lines in urban areas. It typically also does not result in better outcomes for the transportation system.

LOS is biased against smart growth because most urban areas, such as San Francisco, have some existing traffic congestion, whereas projects far away from urban areas and infrastructure have minimal traffic congestion. Therefore, smart growth projects in urban areas that promote sustainable forms of transportation but have some vehicle trips can generate significant traffic impacts under LOS.  Conversely, projects far away from urban areas and infrastructure that induce greater regional vehicle travel often generate no significant impacts under LOS.  VMT is a better measure of these two types of projects’ environmental effects because an increase in vehicle miles traveled results in increased air pollution, including greenhouse gases, as well as increased energy use. 

LOS does not result in better outcomes for the transportation system because a common way to improve LOS is to widen roadways.  In San Francisco, given our space constraints, this is not feasible. We are not going to bulldoze buildings – destroying housing and businesses – to widen roads. Even if there is the right-of-way available to widen roadways and improve LOS, these changes often are harmful to people walking, biking, or taking transit. San Francisco has adopted Transit First, a policy prioritizing transit, and Vision Zero, a commitment to end all traffic fatalities in a decade. Steps to improve LOS conflict with these policies by hindering transit and decreasing pedestrian and bicyclist safety. These steps would increase crossing distances for people walking, increase vehicular traffic levels because of induced demand which can slow down transit, and increase traffic speeds to unsafe levels. Vehicle miles traveled is a better measure because if a project results in a significant amount of VMT, a smarter solution is to provide on-site transportation demand management measures, like subsidized car-sharing or bike-sharing memberships, or improve right-of-way conditions for people walking or taking transit, like wider sidewalks. These VMT reduction measures are aligned with state and local laws intended to improve the environment.

For further information on these two reasons and others, please refer to the State Office of Planning and Research’s Updating the Analysis of Transportation Impacts Under CEQA  webpage.

What is the California Environmental Quality Act?
The California Environmental Quality Act, or CEQA, was enacted in 1970 in response to the growing awareness that environmental impacts must be carefully considered in order to avoid unanticipated environmental problems from planning efforts or development. The environmental review process provides decision-makers and the general public with an objective analysis of the immediate and long-range impacts of a proposed project on its surrounding physical environment. This includes both specific and cumulative effects. In California, environmental review has two purposes: to disclose the impacts of a project and to ensure public participation. For more information about CEQA, please refer to San Francisco Planning’s Environmental Planning webpage and the California Natural Resources Agency’s CEQA webpage.

What is the difference between the CEQA statute and the CEQA Guidelines?
The CEQA statute is the law that is passed and amended by state legislators.  The CEQA Guidelines are the regulations that explain the everyday application of the CEQA statute for both the public and the government agencies required to administer CEQA.

Put simply: CEQA is the law. The guidelines are the rulebook for following the law. The CEQA Guidelines provide objectives, criteria and procedures for the evaluation of projects subject to CEQA. The CEQA Guidelines are developed by the California Office of Planning and Research and certified by the California Secretary of the Natural Resources Agency. 

What will happen to the CEQA process in San Francisco now?
San Francisco Planning reviews every project in San Francisco subject to CEQA to identify any potential adverse environmental effects, assess their significance, and propose measures to eliminate or mitigate significant impacts. This review includes an evaluation of impacts across 18 environmental review topics, including transportation. Based upon this review and whether the project qualifies for an exemption, an environmental document is prepared. This process would not change.

What are the CEQA implications for new development projects?
In San Francisco, for projects that require preparation of a Transportation Impact Study, it is expected that the time it takes to prepare this study would be reduced by approximately 30 percent by no longer requiring a LOS analysis. All other topics currently analyzed in a Transportation Impact Study, such as impacts to people walking, bicycling and riding transit; loading; emergency vehicle access; construction; and site circulation and access would continue to be analyzed for physical environmental impacts.

What are the CEQA implications for new transportation projects?
Because CEQA has required traffic impact analysis to focus on automobile congestion, those studies have treated public transit projects, as well as pedestrian and bicycle infrastructure, as having negative traffic impacts if they should slow cars down.  Based upon the Office of Planning and Research’s Revised Proposal on Updates to the CEQA Guidelines on Evaluating Transportation Impacts in CEQA , transit and non-motorized improvement projects that reduce overall VMT or are intended to improve safety and operations will be considered to have a less than significant impact on VMT. 

When will the CEQA changes take effect?
They went into effect immediately, including for active projects, after adoption by the Planning Commission on March 3rd, 2016.  Going forward, vehicle miles traveled is the significance critria for all CEQA environmental determinations.

How will this affect me?
Individuals: Healthier, more active life-styles, financial savings (e.g., less money spent at the pump), safer streets, and cleaner air.  

Local governments: The proposed changes promote choices in planning communities and in transportation networks.  

Environmentally friendly project developments: Simpler transportation studies and more certainty to the environmental review process.