Abstract
Ensuring accessibility to necessary services is critical for older adults. However, there often exist spatial disparities in the levels of accessibility to services. Because the application of Geographic Information System (GIS) has gained attention in the gerontology field, we used spatial analysis to identify communities of concern for older adults from the perspective of accessibility. We defined the communities of concern based on the proportion of older adults and the level of accessibility to health, social, and daily services via two specific modes of transportation—walking and public transit. Our findings show that newly developed communities tend to have less accessibility to necessary services, and aging communities are randomly distributed across the city. Our results call for interdisciplinary collaboration, between urban planning and gerontology professionals, to better understand the spatial pattern of aging communities and its implication for properly addressing the mobility needs of older adults in the communities.
Regardless of location of residence, every citizen must be provided with the same level of social and community services. It is even more important to provide better accessibility to necessary services for older adults who are often considered a transportation minority. To sustain their own health and well-being, older adults should have both essential and discretionary services within an accessible distance via alternative transportation (a means of transport other than a car). Previous literature has provided empirical evidence of a positive relationship between the level of accessibility to community resources (e.g., parks and grocery stores) and physical activity, which in turn, enables older adults to stay healthy (Li et al., 2005; Yen et al., 2009).
The social-ecological model explains the relationship between environment and health (Bauman et al., 2012; Saelens et al., 2003). Physical activity related to travel (e.g., walking or cycling, which in turn affects individual health outcomes) is associated with several characteristics of a given neighborhood—in particular, the built environment (Todd et al., 2016). A number of studies have demonstrated how walkable neighborhoods (typically described as being high density and having mixed-land use and a grid street network) can increase total physical activity among its residents by encouraging active travel (Frank et al., 2006). In contrast, a suburban neighborhood, often characterized by a low-density residential developments, is likely to lead to a heavy reliance on automobiles, which is correlated with physical inactivity that worsens health outcomes (Bauman et al., 2012).
Spatial disparity in accessibility to necessary services within a given area usually happens in practice. As a city’s boundaries extend outward, outer communities are likely to experience limited access to necessary amenities for several reasons—the first being related to the built environment (e.g., low-density developments with single land use and a lack of transit provision; Pearce et al., 2006). Despite the spatial disparity in these areas, there have been few studies with spatial analysis in gerontological research and practice (Hirshorn & Stewart, 2003; Horner et al., 2015; Yamashita & Kunkel, 2012). Quality of life for older adults highly depends on the accessibility to necessary services, and their neighborhood built environment should support them through appropriate community-level planning practices.
Thus, this study aims to identify communities of concern for older adults in Calgary by mapping out the communities based on the size of the aging population and the level of accessibility to necessary facilities while applying community as a unit of analysis. By identifying communities with low accessibility to needed facilities via walking and public transit, the local government can prioritize changes in certain communities to make them accessible for older adults.
Method
Study Area and Data
Calgary is one of the fastest-growing and rapidly aging cities in Canada. According to the 2019 civic census, the population of those 65 years and older accounts for approximately 12% of the city’s population. The city has developed new communities on the edge of town to accommodate its population growth in the past few decades. These communities often have a lack of access to necessary services by alternative transportation partly due to the delayed public transit service provision. In addition, the neighborhoods have automobile-oriented designs. Although Calgary’s public transit system is well established, only 20% of communities are directly connected to the light rail transit (LRT) service; in addition, bus ridership is low. In general, Calgary is considered a car-dependent city, although many of the inner-city communities are walkable. To establish measures for this study, we accessed 2016 Calgary civic census information via the city’s open data portal, which includes community-level demographics and the city’s proprietary street network and facility data sets related to our area of interest.
Measure
Aging community
Adopting the definitions of aging society from the World Health Organization (WHO), we used the 7%, 14%, and 20% of older adults who are aged 65 and older out of the total population to indicate the pace of population aging by naming “aging,” “aged,” and “super-aged” communities, respectively. Using these categories, we created a map showing Calgary communities based on these aging definitions.
Accessibility
Considering the reduced ability of older adults to drive or bike, we focused on two modes of transportation (LRT/bus and walking) as related to access to three categories of services: health (hospitals and community health centers), social (community centers and public libraries), and daily (parks and grocery stores).
Analysis
In many disciplines, Geographic Information System (GIS)-based methodology has been widely used to assess and measure transportation accessibilities (Finch et al., 2019; Ozel et al., 2016). We utilized ArcMap 10.7.1, which is the central application used in ArcGIS. To identify aging communities, we calculated the proportion of the population 65 years and older for individual communities. To measure accessibility to necessary services, we started with creating walksheds and transitsheds from the six facilities (i.e., hospitals, community health centers, community centers, public libraries, parks, and grocery stores). Then, we rasterized the walksheds and transitsheds and assigned scores based on distance or time from those facilities. Finally, the accessibility scores were aggregated at the community level.
Creating walksheds and transitsheds
A walkshed refers to a walkable area to/from a specific point of interest. We were interested in visually determining how accessible specific facilities were based on different walking distances. Specifically, we created walksheds of individual facilities with distance parameters of 200, 400, 800, 1,200, and 1,600 m. A distance of 400 m is deemed a 5-min walking distance at the average walking speed. Considering relatively slower walking speed for older adults, we included an additional distance parameter of 200 m. Unlike walking trips, transit trips are influenced by the transit schedule. To account for a real-time transit schedule, we considered the General Transit Feed Specification (GTFS) data in our analysis. Then, similar to the process of creating walksheds, we created service areas for transit accessibility based on specific time intervals such as 10, 20, 30, 45, and 60 min. The other parameter is the time of day, and we specifically used the transit schedule of 10:00 a.m. on Wednesday. Figure 1 illustrates examples of a walkshed and a transitshed.
Examples of walkshed (left) and transitshed (right).
Raster analysis and statistics for walksheds and transitsheds
To retrieve statistical values for each community based on the walksheds and transitsheds, we performed the following process. First, all service area polygons (both walksheds and transitsheds) had to be dissolved at the specific distance value. Second, we assigned integer values to these polygons so that higher values indicated shorter distances and travel times (Table 1).
Value Assignment to Individual Cells.
Each set of dissolved polygons for a specific facility was then converted to a raster. Using the 25-m raster cell size, we assigned integer values to individual cells with respect to distance and time. Once we created all rasterized maps with cell values, we summarized them into a single rasterized map for the walk and transit statistics calculations. As a result, we created two separate rasterized maps for walksheds and transitsheds, where the separate raster cell values were added up so that each final cell value could be interpreted in terms of good and bad walkability (range = 0–23) or transit accessibility (range = 0–29) to six facilities overall. Last, we calculated statistics on the raster values within the boundary of each community.
Results
Among 204 Calgary communities, 79 communities (38.7%) were classified as “aging,” 45 communities (22.1%) were considered “aged,” and 26 communities (12.7%) were “super-aged” communities. In other words, more than three quarters of Calgary communities are in the process of aging. These communities seem to be located randomly across the city (Figure 2).
Community map with aging status.
Figure 3 shows the mean accessibility scores for individual communities (size varies) within the city limits. The darker-colored communities represent communities with better overall walking and transit accessibility to services, whereas the lighter-colored communities show a relatively lower overall accessibility. It is obvious that communities with higher accessibility are located in a relatively central location, whereas communities with lower accessibility are likely located in the outer suburbs. Furthermore, it is noted that the communities with lower accessibility tend to be younger.
Community accessibility maps: Walking (left) and transit (right).
Table 2 lists the selected 26 super-aged communities and their demographic characteristics and walking and transit accessibility to services. Based on the accessibility scores and the aging status of a respective community, we identified eight communities of concern for older adults in Calgary that show either or both accessibility scores below the regional averages. These communities are bolded and shaded in Table 2.
List of Super-Aged Communities With Accessibility Scores by Walking and Transit.
Note. The average levels of accessibility by walking and transit for the entire city are 5.30 (SD = 3.02) and 18.06 (SD = 5.32), respectively. Based on the accessibility scores and the aging status of a respective community, eight communities of concern for older adults in Calgary were identified that show either or both accessibility scores below the regional averages. These communities are bolded and shaded.
Conclusion
From the findings, we derived several policy and practice implications. Among the eight identified communities, six are considered established communities, meaning those that were developed between 1960s and 1980s. Those particular communities are Shawnee Slopes, Maple Ridge, Point McKay, Parkland, Varsity, and Midnapore. The two new communities, Seton and Greenwood/Greenbriar, are still developing. From the planning perspective, the six established communities of concern of older adults are apparently bedroom communities with single-family detached houses and a limited number of community amenities. To address this issue, needed facilities should be provided nearer to these communities if there is developable land within proximity. For instance, one LRT station located in the Shawnee Slopes community has an adjacent area used primarily for surface parking lots. This land could be developed to retrofit the station area with features that facilitate easy access for the older adults of the community.
Unlike the older communities, the two newer communities of concern had more amenities and diverse housing options. Most of Calgary’s new master-planned communities are likely to have a mixed-use village center to serve its residents, usually equipped with grocery stores, restaurants, and social destinations. Although older residents benefit from living in this type of neighborhood, they still need to travel to other communities for certain services (e.g., hospital visits). In this regard, it would be critical to connect newer communities to those with the necessary amenities by extending the existing transit service or introducing a new transit service.
In this study, we identified communities of concern for older adults in Calgary by measuring accessibility to health, social, and daily services. Our findings suggest that aging communities are randomly distributed across the city, and newly developed communities tend to show lower accessibility to the services of our interest. Another implication for the current study is that spatial analysis of the community can help ensure a better quality of life for older adults by highlighting the lack of accessibility to resources in the community. Given that the spatial data are available in many municipalities, the application of GIS to perform spatial analyses can be adopted to other areas or regions not only to gain better understanding of the spatial patterns of necessary resources for older adults but also to identify communities of concerns for them.
This study, however, has some limitations that need to be addressed in future research. First, our findings are aggregated regardless of potential differences across the generational age groups (Black & Hyer, 2020). Second, there could be a number of the relatively young-old people (e.g., baby boomers) who still use a car as their primary mode of transportation. Last, we did not address the possibility of older adults moving from one facility to another. Future studies should address these limitations while taking all modes of transportation into consideration.
Footnotes
Acknowledgements
This research was also possible thanks to the support of Oak Foundation through the Richard Parker Professorship in Metropolitan Growth and Change.
Declaration of Conflicting Interests
The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
Funding
The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This research was made possible thanks to the generosity of Grant Allen, philanthropic gift (#10020127) made in honour of his late wife, Patricia Allen (1924–2017), founder and former CEO of the Kerby Centre, through the Faculty of Social Work at the University of Calgary. The late Patricia Allen dedicated her career to improving the quality of life for seniors.
