The Site Analysis: Mobility + Pollutions

Though a hub for economic flow, the 9.3 square mile Inner Loop remains difficult to access for elderly and low-income residents due to the downtown’s car-centric design. The Inner Loop is surrounded by two interstate highway systems and includes a road network of primarily bidirectional arterial lanes. This presents a challenging landscape to traverse for residents who do not own vehicles.

Furthermore, the American Lung Association classified Maricopa County—inclusive of Phoenix and the surrounding cities of Chandler, Glendale, Mesa, Scottsdale, and Tempe—within its lowest ranking for environmental quality in part due to the dangerous confluence of road noise, air pollutants, and heat at the Inner Loop’s interstate entry and exit points toward the center of downtown. Pollution places those with respiratory challenges, such as the elderly, at greater risk. Rice University reports that poverty and the proportion of older and younger residents are growing fastest in Sun Belt Cities and Arizona State University found evidence that Hispanic and poor communities in Phoenix experience more extreme heat compared to their White and wealthy counterparts.

The Inner Loop has wide public transportation coverage, which should reduce traffic volume and improve air quality. However, the service has experienced limited ridership, with roughly 75% of commuters traveling to work by car historically and currently. Stations with high ridership (i.e., bus stops with greater than 71 riders per day are co-located with areas of high automobile traffic, exposing riders to higher noise and air pollution levels. The City of Phoenix thus seeks to reduce use of singleoccupancy vehicles to improve residents’ health and quality of life.

Regional air pollution map

Source: AZDOT