Planning With A Eye Toward Health Equity
Transit-oriented housing development is great for density and walkability. What about air quality? Michael Austin, Project Manager for Corgan’s Urban, Campus and Cultural sector, explains why planning for health equity requires a different approach to transit-oriented development.
Bringing public health along for the ride
As local agencies and elected officials work to address the housing crisis, many are looking toward transit corridors for land to develop residential buildings. Numerous regions throughout the nation are experiencing a surge in transit investments, such as light rail and bus rapid transit, which depend on building up nearby ridership. We know that creating transit-oriented districts can have major public health benefits: By concentrating mixed-use development near public transit, residents' mobility and access to food and services increase, without the need to drive.
But for optimal public health outcomes, it's essential for planning practitioners to guide decision-makers about the harmful effects of locating housing along freeways and arterials — areas where land is often the easiest to develop. We must implement policies and design strategies that avoid repeating past mistakes and jeopardizing residents' health.
Looking beyond conventional wisdom
Living next to freeways and arterials is a known health hazard — the data is clear, as noted in a U.S. Environmental Protection Agency report. Los Angeles, often seen as the epicenter of car culture, is a prime case study. Comprehensive articles and academic studies highlight the harmful impacts of living near major roadways, yet development in these areas continues despite known risks. Thus, it is important to prioritize public health in planning decisions.
A first step is dispelling two pervasive myths, that switching to electric vehicles and planting trees will solve air quality issues. While vehicle electrification reduces automobiles' toxic emissions, it doesn't eliminate all harmful particulate matter. In fact, certain types of emissions may even increase. Moreover, the residual noise, odors and other sensory impacts of living near roadways are left unaccounted. Urban tree canopies do help soak up particulate matter, but they are not a standalone solution. Noise and smell, two critical factors affecting personal wellbeing, aren't significantly mitigated by trees alone.
A comprehensive approach is necessary to protect public health
When developing transit-oriented developments (TODs) along active corridors, it's important to prioritize housing that's set no closer than 500 feet — and ideally, 1,000 feet — from major arterials and freeways, as suggested by UCLA researchers and the California Air Resources Board. Focusing particularly on affordable, family-size and senior housing, as well as support services like healthcare and childcare provides essential housing in these developments. Concentrating a mix of commercial, retail, office and civic uses closer to transit stations keeps these areas active and reduces the public's direct exposure to road pollutants.
We can see that illustrated in the following examples of how these buffers can be applied:
Expand TOD boundaries beyond the commonly aspired 10-minute "pedshed," or walkable area, to help advance walkability into areas with higher livability, such as neighborhoods with mature tree canopies, parks and schools. While a careful study of access and public realm quality is essential for each location, the safe distance from freeways and arterials will benefit residents' wellbeing.
Bellevue, Washington's design guidance for the East Main Transit-Oriented District (along I-405 to support the Sound Transit Eastlink expansion) was one of the first approaches to incorporate air quality considerations into land use code. The city's Air Quality and Land Use Planning report provides a model for integrating research to inform potential city-wide recommendations — for instance, strategies that address air quality and traffic-related air pollution, land uses next to high-volume roadways, and development alternatives that balance limited exposure to air pollution with the community's growth.
While it may be tempting to locate housing in industrial areas, particularly with the push to increase housing supply, industrial zones remain critical economic engines and are not suitable for residential development because of their association with harmful toxins. As Seattle's Industrial and Maritime Strategy report highlights, mixing residential with industrial uses creates conflict and devalues both spaces.
Committing to a collective approach
As planners, we have a responsibility to uphold ethical standards, including promoting economic, social and racial equity. Continuing with the "business as usual" approach only perpetuates the race-based inequities we're working to dismantle.
Public health resources, such as those provided by Seattle-King County Public Health, offer valuable guidance on integrating health considerations into decision-making. These resources are essential in ensuring our communities can access healthier living spaces, from parks to high-quality grocery stores. By implementing smart design and policy, a collective approach can make a difference.
