This project recommends that green space investments should be considered in Aurora and North Denver to counteract long-term and racialised systematic disinvestment in these neighbourhoods through practices of redlining and discriminatory urban planning. People living in these neighbourhoods do not only have low levels of residential park access relative to the rest of the conurbation (Maps 5-8) but are also exposed to high levels of environmental hazards, which green space interventions could work to ameliorate. Green spaces reduce harms to health by cooling the neighbourhoods around them and by offering a sanctuary from the noise and pollution of the city to the urbanites who use them. 

North Denver experiences high levels of Heat Severity in almost all neighbourhoods, while other neighbourhoods have only patches of heat severity, even if more extreme (Map 9). This means that there is almost no space to seek respite from the heat for residents in these neighbourhoods.

Furthermore, both Aurora and North Denver experience very high levels of transportation noise (Map 10) relative to the rest of the conurbation, as highways run past and through many lower-income, Black, and Latino neighbourhoods in the urban area. These noise inequalities are a product of the systematic allocation of disposability along lines of race and income that characterises much of America’s post-war freeway planning. This is accentuated by how North Denver and Aurora experience higher levels of pollution than some of the wealthier suburbs in the South of the city (Map 11), in part because more cars and highways run through these neighbourhoods than in other parts of the conurbation.

Where green space needs to be created in Denver-Aurora-Lakewood is clear. The question is now how more green space can be provided in Aurora and North Denver without the displacement of existing populations through processes of green gentrification (Safransky, 2014; Anguelovski et al., 2019; Penney, 2020).

Methods

To identify which areas of Denver-Aurora-Lakewood have the best and worst provision of green spaces within a 10-minute walk of residential addresses, a network model was built using OpenStreetMap (OSM) Road and Path line data to compute service areas for all entrances to urban green spaces (parks and nature reserves) in Denver-Aurora-Lakewood. These service area walksheds were then used to assign the time taken to walk to an urban park entrance to each residential address in Denver-Aurora-Lakewood. This data was generalised to the Census Block Group level, as a proportion of residential addresses in each block group that can access a park within a 10-minute walking distance. This was compared with socio-economic and environmental data to make subjective judgements on where in Denver-Aurora-Lakewood is most in need of macro-scale green space interventions. A 10-minute walking distance (half a mile) is generally considered to be the furthest people are willing to regularly walk to access a green space (Wolch et al., 2005; Boone et al., 2009; Rigolon, 2017).

The network approach to calculating the service areas of urban green spaces was selected over a straight-line radius approach. A straight-line radius, or buffer, approach to calculating the service areas of urban parks does not consider the positions of a park’s point(s) of access and does not realistically account for the real distance taken by park users to access a park, as it assumes that movement is free and possible in all directions (Figure 1). A network approach more closely emulates the actual routes that users are likely to follow between residential addresses and points of access to urban parks by measuring distance along roads and public rights of way to parks rather than in a straight line (Nicholls, 2001). Figure 1 makes this clear.