Background
Urban planners and sociologists have debated and theorized about what constitutes a neighborhood since the turn of the 20th century. Neighborhoods have been defined in both social and physical terms. The geographic boundaries of neighborhoods expand or contract based on people's daily activities and sociodemographic background. For research purposes, neighborhoods are important spatial units of sampling, measurement, and analysis. In practice, they are key spatial units of intervention, planning, and organization. Programs promoting active living in communities depend on operational definitions of walkable neighborhood that include the identification of the physical environmental characteristics that support walking, and the spatial delineation of neighborhood boundaries.
Objectives
This paper seeks to define walkable neighborhoods based on their objective spatial characteristics. Empirical research findings lead to considering the following characteristics: (1) detailed land use and infrastructure conditions significantly associated with walking; (2) the range of neighborhood spatial extents related to walking behaviors; and (3) neighborhood boundaries corresponding to people's perceptions of neighborhood and their walking behaviors. The paper compares the research findings with urban planning and sociology theories to improve the conceptualization and measurement of walkable neighborhoods in urban and suburban settings.
Methods
Subjective data come from a telephone survey covering walking behaviors, demographics, household characteristics, attitudes, and neighborhood perceptions (n=608, randomly selected adults living in urbanized King County of Washington). Objective data on physical environment are derived from a 500,000-parcel and network Geographic Information System (GIS) databases. They include individual respondents' physical neighborhood characteristics captured from 1-km and 3-km buffer areas around their homes; and proximity to 24 individual destinations and 11 neighborhood centers (groups of destinations) known to attract walking. Multinomial logit models estimated the likelihood of walking moderately (<150 minutes/week), and sufficiently for health goals (150+ minutes/week), against not walking. They identified individual physical environmental variables significantly associated with walking, controlling for important confounders from the survey. Descriptive statistics and bivariate analyses determined individual neighborhood boundaries. Perceived attributes of the physical environment were compared with actual (GIS) attributes to define salient neighborhood boundaries.
Results
The models show that the presence of and distance to specific destinations and groups of destinations near home are important indicators of walkability. Grocery stores/markets and non-fast-food restaurants stand out consistently as positively associated with walking sufficiently for health purposes. Environments with large offices and schools are negatively associated with walking, while parks and trails are not significant. Smaller block sizes and more complete sidewalks along major streets, as well as higher residential density of the respondents' parcel, are associated with increased walking. On average, people who walk sufficiently live within about 0.3 miles of a grocery store and a restaurant. For grocery stores, schools, and parks, respondents generally perceive these land uses to be within their perceived neighborhood limit when they are located within approximately a quarter mile to a half-mile radius from home. Neighborhoods boundaries for such recreational facilities as fitness center, sports facilities, and trails become larger ranging from 0.6 up to 1.75 miles. People generally perceive and construct geographically smaller neighborhoods when considering residential compared to commercial uses, and multifamily compared to single-family development.
Conclusions
Walkable neighborhoods appear to be definable objectively and spatially. The importance of nearby routine utilitarian walking destinations, such as grocery stores and restaurants, points to changes in lifestyle and family composition already highlighted in consumer behavior research. This finding suggests rethinking planning models, which typically have anchored neighborhoods around community centers, schools, and parks. The strong positive role of density at the respondent' parcel level, combined with the short distances to attractors of walking, suggests that walkable neighborhoods take the form of nodes of concentrated development. Within these nodes, residential and commercial land uses may be segregated spatially but they remain in close proximity. An operational concept of mixed-use neighborhood thus involves a precise measurement of the residential and daily retail environments and distances between them. The limits of a neighborhood spatial extent are constantly negotiated depending on people's daily behavior and experiences and related types of proximate land uses. Commercial neighborhoods appear to be perceived as larger than residential ones, likely because the automobile is the prevailing mode of access to commercial activities. Neighborhoods involving recreational activities are generally larger than those involving utilitarian activities. Despite these variations, neighborhood boundaries for the purpose of walking appear to be around a quarter to a half-mile from home or neighborhood centers.
