We have come across two articles over the past week on the environmental impact of parking spaces, based on calculations on the number of vehicles and parking facilities in the US.
One study, “Parking infrastructure: energy, emissions, and automobile life-cycle environmental accounting” by Mikhail Chester, Arpad Horvath and Samer Madanat, calculated that there could be up to three parking spaces for every car on the road (therefore around 800 million car spaces). The analysis found that besides the heat island effect, parking spaces increase sulfur dioxide and soot, resulting in 0.5% to 12% of total estimated lifecycle energy consumption and greenhouse emissions, and 24% to 81% of other air pollutants, depending on vehicle type and scenario.
The second article, from New Scientist, reports that the tar sealers widely used in the US to coat blacktop driveways, parking lots and paved playgrounds are contributing significant pollution to urban and suburban lakes, as well as air pollutants. While many cities in the US are now moving to ban the coal-tar sealers that have been linked to these increased pollutant levels, the impact of the existing car parking spaces will continue to have an effect on water and air quality for many years to come.