While concerns about traffic safety were central to the development of conventional community design practice, there has been little empirical examination of the relationship between community design and the incidence of traffic-related crashes, injuries, and deaths. The authors examined the relationship between community design and crash incidence. They present a brief historical review of the safety considerations that helped shape conventional community design practice and then analyze GIS data on crash incidence and urban form using negative binomial models. They found that many of the safety assumptions embedded in contemporary community design practice are not substantiated by the empirical evidence. While disconnecting local street networks and relocating nonresidential uses to arterial thoroughfares can reduce neighborhood traffic volumes, this does not appear to improve safety, but rather substitutes one set of safety problems for another. They found urban arterials, arterial-oriented commercial developments, and big box stores to be associated with increased incidences of traffic-related crashes and injuries, while higher-density communities with more traditional, pedestrian-scaled retail configurations were associated with fewer crashes. They found intersections to have mixed effects on crash incidence. They conclude by discussing the likely reasons for these findings (vehicle operating speeds and systematic design error) and outline three community design strategies that may help improve traffic safety. (Author/publisher)
Abstract