Sustainable Communities Index

Indicator PR.3.a Recreational Area Score

Why Is This An Indicator Of Health and Sustainability?

A review of studies showed that access to places for physical activity combined with outreach and education can produce a 48 percent increase in the frequency of physical activity.^a Evidence also shows that contact or views of the natural environment can improve functioning in children with Attention Deficit and Hyperactivity Disorder (ADHD) and problem solving and cognitive function in people living in public housing.^b,c More generally, living in proximity to green space is associated with reduced self-reported health symptoms, better self-rated health, and higher scores on general health questionnaires.^d Finally, children who live in close proximity to parks, playgrounds, and recreational facilities tend to be more active compared to children who do not live near those facilities.^e  Adolescents who engage in moderate physical activity five or more times a week are more likely to achieve an ‘A’ in math and science than their peers.^f

Methods

To calculate the Recreational Area Scores, the distance from each residential intersection (intersections within 100 meters of residential lots) to recreation spaces (park, natural area, or recreation center) within 2 miles of the intersection is calculated. A distance of < 0.5 miles is given a score of 1, while distances between 0.5-0.1 miles are given a score of 0.75 and distances >1 mile are given a score of 0.5.

In order to make sure that large parks in the city do not overly skew the distribution of relative access to recreation spaces, a formula for diminishing returns is applied to each park’s acreage. The assumption is, that as a park’s acreage becomes increasingly large, additional acres add less and less value. Thus, the formula used is:

Diminishing Return Adjusted Acreage = (actual acreage x acreage cap)/(actual acreage + acreage cap)

An acreage cap of 250 acres was chosen because parks of 250 acres or more are in the largest park category of regionally serving parks, as specified by the National Recreation and Parks Association. Thus, additional acres could not advance a park of 250 acres or more into a higher category and would not add significantly more value.

Distance weights are then multiplied by the diminishing returns adjusted acreage for each recreation space within the 2 mile search radius. These products are then summed for each intersection, for a sum of “distance weighted acres.” The distance weighted acres for each intersection are then normalized to a scale of 0-100 to create a Public Recreation Access Score.

Public Recreation Access Scores for all of the residential intersections in the city are interpolated onto a continuous surface in ArcGIS using an inverse distance weighting (IDW) technique, with an output cell size of 30 and a variable search radius that samples the 12 nearest points.

Neighborhood averages are calculating by using the “zonal statistics by table” tool in ArcGIS to calculate the averages for neighborhood boundaries.

Limitations

The analysis here relies on total accessible acreage as a measure of public recreation space quality. However, the quality and utility of recreational spaces is influenced by many other factors beyond land area, including the range of facilities, like playgrounds, sports fields/courts, swimming pools, bathrooms, etc., and the safety and cleanliness of the space. Many small parks may have numerous high quality facilities, while some of the larger parks may be relatively unimproved or poorly maintained.

Additionally, many other factors besides distance influence the accessibility of a recreational space, such as the presence of major roads, highways, buildings, steep hills, and gates; one’s mobility status; and whether a neighborhood is safe enough to travel through.