Livable arterials, not necessarily an oxymoron

By Eric Sundquist

Perhaps nowhere is the conflict between mobility and livability more apparent than along arterials. One problem in improving livability is that, while practitioners have multiple well-established standards for mobility, they have none for livability. Since “what gets measured, gets managed,” livability tends to go unmanaged. In many cases we have simply built for mobility, with unfortunate results for areas along and near arterials.

Into this gap step Carolyn McAndrews and Wesley Marshall of the University of Colorado-Denver. Their new study surveys residents near 10 arterials in Denver, in order to better understand what factors contribute to livability. Neighbors’ perceptions are summarized along four axes – including the intriguingly designated “social sketchiness” axis – in Figure 1.

Figure 1. Ten Denver arterials rated on four livability factors; factors and ratings derived from neighbor surveys.

While the study stops short of providing guidance on the relationship between speed or other characteristics practitioners could expect, it does point in that direction, noting that vehicle volume seems less important than other arterial attributes.

The low-traffic arterials in our study—arterials with about 12,000 vehicles per day—are not necessarily associated with more livable neighborhoods than their higher traffic counterparts. A low-traffic arterial with fast-moving traffic that does not offer sidewalks, transit access, or useful establishments feels dominated by traffic. These findings suggest that residents may not perceive differences in actual traffic volumes, but they do notice pedestrian-oriented design elements, commercial establishments, cleanliness or the lack thereof, and the comfort they feel along the arterial.

The study concludes with some steps to improve livability:

Our research suggests three specific types of planning interventions that could enhance the livability of arterials in ways that matter to adjacent neighbors: 1) Encourage active land uses, such as restaurants and other commercial establishments, that serve nearby residents; 2) maintain the arterials effectively, control litter and graffiti, and reduce neighborhood neglect and decay; and 3) enhance the pedestrian environment in ways that support transit access and reduce exposure to traffic hazards. Each of these interventions is a departure from the traditional approach to arterial planning because none focuses on motorized traffic per se, although each links to traffic in important ways.

Eric Sundquist is Director of SSTI.