California Air Resources Board

SACRAMENTO - The California Air Resources Board (CARB) today issued a guide designed to provide public health, air quality and urban planning policy-makers with options for reducing exposure to traffic pollution for those who live or work near busy roads.

“Infill developments are crucial to California’s ability to meet our air quality and climate goals,” said CARB Chair Mary D. Nichols.  “They put people close to public transit, reduce the need to drive, and promote biking and walking.  The health benefits of denser urban neighborhoods can be reduced if they are built close to congested highways.  This guide provides planners and builders of infill developments a range of science-based strategies to protect public health and reduce the impacts of nearby traffic.” The guide, Strategies to Reduce Air Pollution Exposure Near High-Volume Roadways, is a technical advisory that addresses concerns raised about the potential health implications of living and working in existing or planned developments near busy roads.  The strategies are options that planners and others can put into place to protect public health in developments close to freeways and as “infill” development, which is the opposite of urban sprawl, continues.  

This is especially important in urban areas where the freeway network is dense, which means there are few places that are not near a freeway.

Strategies identified in the technical advisory fall into one of three categories: they reduce traffic emissions, reduce the concentration of air pollution from vehicles, or remove pollution from our air. The strategies were chosen based on peer-reviewed scientific literature and CARB-sponsored research projects. Examples include the use of traffic roundabouts instead of stoplights to reduce stop and go driving, sound walls and vegetation that help dispel pollution, and air filters in buildings that remove pollutants from indoor air.

The new technical advisory supplements the Air Quality and Land Use Planning Handbook issued in 2005, and is a companion document to the forthcoming updated General Plan Guidelines from the Governor’s Office of Planning and Research.  

Infill development promotes biking and walking, and shortens distances that people must travel for their daily activities.  Dense developments also support transit operations, and can improve quality of life by facilitating community connectivity.

“These are scientifically based strategies that can be used at the local level to reduce exposure to air pollution in the near future while we work toward full implementation of California’s progressive regulations that are cleaning the air but are being phased in over time,” said Chief of CARB’s Research Division Bart Croes.  

“As California grows, we have the collective opportunity to shape the future of the built environment to be both protective of public health and supportive of environmental goals,” said Croes.  “We hope that this new guide will help decision makers promote healthy, safe, equitable and sustainable communities.”

For more information and for Fact Sheets in English and Spanish, please visit https://www.arb.ca.gov/ch/landuse.htm