Local, regional, and state agencies in California are making efforts to increase bicycle infrastructure and ridership. In most areas, bicycle routes are a subset of vehicle routes and new bicycle infrastructure is created by adding bicycle lane(s) to existing roadways. The planning process for identifying bicycle routes typically considers available right-of-way, existing roadway infrastructure (e.g., presence of bridges, number of intersections), vehicular traffic volume, safety concerns, and built environment factors (e.g., attractive land uses such as shopping districts, scenic views), among other factors. However, exposure to traffic-related air pollution is rarely considered in this process. This oversight can have negative impacts on bicyclists given they are directly exposed to vehicular exhaust and experience an increased breathing rate during biking. Exposure to traffic-related air pollution has been proven to contribute to a wide range of health problems such as lung and heart diseases.

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In urban areas, many socio-economic concerns have been raised regarding fatal collisions, traffic congestion, and deteriorated air quality due to increased travel and logistic demands as well as the existing on-road transportation systems. As one of the promising remedies, active transportation has been advocated, which may not only mitigate congestion on local streets, but also promote physical fitness, foster community livability, and boost local economy. To promote the active transportation mode, extensive work has been focused on planning and developing a number of pedestrian and bicyclist related programs which require the infrastructure, e.g., sidewalks, as a premise. A significant amount of these efforts have to go for the setup, maintenance and evaluation of the sidewalk inventory on a relatively large geographic scale (e.g., citywide, statewide), which lays a solid foundation for a variety of active-mobility-focused applications and related research.

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Traditional Intelligent Transportation System (ITS) applications aim at improving safety and mobility for roadway transportation. With increasing concern about energy consumption and pollutant emission of transportation sector, a number of environmental-ITS applications have emerged to improve fuel economy and reduce overall emissions. Further, mobile emissions disperse into the atmosphere and impose health risks to public population who are exposed to the contaminated air. To date however, environmental-ITS applications haven’t considered emissions from a pollutant exposure point-of-view. This dissertation proposes two environmental-ITS applications and a high-resolution screening method to mitigate human exposure to mobile pollutants. The key contributions are:

• This dissertation develops a vehicle road navigation method to mitigate mobile-source exposure to a localized susceptible population. Routing experiments show that 50% of 400 experiment trips achieve 30% inhaled mass reduction for both mobile-source PM2.5 and Reactive Organic Gases. Also, the low exposure routes can be more fuel efficient than conventional least duration routes.

• This dissertation defines a state-of-practice digital sidewalk system and proposes a pedestrian navigation tool with the goal of minimizing pedestrians’ inhaled mass of on-road traffic emissions. Pedestrian routing experiments demonstrate that the navigation tool is able to advise walking trips that significantly reduce pedestrians’ PM2.5 exposure up to 90%. As a result, pedestrians can be protected from excessive pollutant exposure.

• This dissertation also develops modeling techniques for large-scale pollutant exposure assessment for Southern California Association of Governments (SCAG) residents, with spatial analysis resolution fifty times higher than previous research. In conjunction with socioeconomic parameter analysis, results reveal that in the SCAG region, low-income and minority population are subject to high-level vehicular emission exposure. This study makes it possible for community outreach and mitigation planning targeted at disadvantaged residential communities.

The frameworks in this dissertation provide valuable implications for environmental transportation and justice research. Future improvements can be focused on real-time population activity collection, exposure assessment, and navigation implementation in the real world.