Could a former shopping centre, its car parks and access roads accommodate more homes, shops and public spaces without recreating the distances that make a car essential? In the United States, several redevelopment projects are trying to answer this question. Their climate value lies less in a promise of a “green neighbourhood” than in concrete planning choices: where to build, how to connect destinations, and how much space to leave for water and open spaces.
These transformations do not eliminate emissions on their own. They can, however, change the conditions that encourage them, particularly car journeys and buildings’ energy consumption. Their impact depends on what is actually built, the transport available and the uses that take hold.
Reusing already-developed sites
After decades of suburban planning organised around big-box retail, extensive car parks and detached houses, some projects are reinvesting in sites that have already been built on. This approach, sometimes called “redevelopment of existing sites”, involves adding homes, businesses and public spaces in areas whose infrastructure or buildings no longer meet local needs.
In Austin, the former Highland Mall has given way to a neighbourhood centred on a community college campus, with homes, offices, restaurants, green spaces and educational facilities. The site of the former Mueller airport, also in Austin, has likewise been transformed into a neighbourhood where destinations are close together. These examples are not interchangeable: they show that an underused site can accommodate functions different from those originally intended.
In Wyandanch, in the town of Babylon on Long Island, the municipal Wyandanch Rising programme aims to revitalise the centre of the community. The municipality describes a project comprising 240 affordable or workforce homes, 50 000 square feet of retail space, a new railway station, a public square and roadworks. The programme also includes pre-apprenticeship training for the construction trades and support for small businesses. These are objectives and elements announced by the municipality, not a measure of emissions reductions.
The climate link runs through travel
In a neighbourhood where homes, shops, schools, offices and leisure spaces are far apart, a car often becomes necessary for everyday journeys. Winding roads, cul-de-sacs and vast car parks can reinforce this dependence by organising the area around the car rather than walking, cycling or public transport.
Bringing several destinations closer together can therefore make some journeys easier without a car. But density alone does not establish that residents will drive less: the outcome also depends on how well routes connect, public transport provision and how services are distributed. The Pike District in Maryland illustrates this sought-after combination. Since 2010, the county and its partners have been working to transform a four-mile suburban corridor into a mixed-use area, linked in particular to rail, a rapid bus service and cycle paths.
The form of housing also matters. Detached houses generally require more energy to heat or cool than homes that share walls, such as flats or terraced houses. Redeveloping a site can therefore affect both distances travelled and buildings’ energy needs. These are plausible mechanisms; their actual effect depends on the project and how it is occupied.
Rain and heat also depend on the ground
An impermeable car park prevents some rainwater from soaking into the ground. During heavy rainfall, water then runs off more quickly into drainage networks and waterways, which can increase the need to manage runoff. Replacing some of the tarmac with open spaces, permeable surfaces or water-retention features can help ease this pressure, provided they are designed and maintained appropriately for the site.
The space given to vegetation and open spaces also changes the neighbourhood environment. The effect of redevelopment depends on the layout of the streets, the surfaces that are transformed and the design of public spaces. A park announced as a response to flood risk therefore does not, on its own, guarantee protection from every rainfall event.
At Ballantyne, near Charlotte, the Ballantyne Reimagined project plans to turn a large business park into a denser, mixed-use neighbourhood. The development company LandDesign describes Stream Park in particular, a six-acre space created on part of a golf course, with a redesigned pond to help manage stormwater and a restored stream. The company says work is under way. These details describe a design and construction work, not a climate outcome that has already been measured.
Local priorities, results to be assessed
Climate is not always the primary reason for these projects. The closure or decline of a shopping centre can deprive a community of tax revenue; housing construction also responds to local demand. Developers may be seeking shops, jobs, public spaces and better transport links at the same time. Redevelopment is therefore as much an urban planning trade-off as a climate policy.
Access matters too. In Wyandanch, the municipal programme combines affordable and workforce housing, training and support for local businesses with the transformation of the town centre. These objectives give the project a social dimension: the benefits of a more accessible neighbourhood depend on who can live and work there and use its facilities. Municipal intentions, however, are not enough to establish what results have been achieved.
To assess the climate benefit of redevelopment, it is therefore necessary to look at what is actually built and used: the proportion of journeys made without a car, the transport available, buildings’ energy needs and how the site absorbs or channels water. Reusing an already-developed site may avoid shifting expansion onto other areas, but it guarantees neither that no new land will be developed nor a measured fall in emissions. The decisive change lies in how the neighbourhood functions day to day.
References
- Yale Climate Connections, “The suburbs are getting a makeover. That’s a climate win.”
- Town of Babylon, Wyandanch Rising
- LandDesign, Ballantyne Reimagined Infrastructure
A space on the Highland campus of Austin Community College, located in a former shopping centre.
