Removing paving exposes the soil again to rainwater and air. The removal of pavement allows for the revegetation of land with trees and plants and the reinstatement of soil ecosystems. By allowing rainfall infiltration and reducing water runoff, stormwater flows that carry toxic urban pollutants to local streams and rivers are reduced, to the benefit of water quality and riparian habitats. Because pavement increases the summertime temperatures in cities and suburbs, this contributes to the formation of ground-level ozone – the main constituent of smog, so de-paving improves air quality and reduces the “heat island effect”, which often making city temperatures several degrees higher than surrounding rural areas. This in turn reduces the need for electricity to power fans and air conditioning units. Removing pavement also reconnects people with the natural world.
In many cities, over half of the urban land is paved for roadways and parking lots. Impervious surfaces such as concrete and asphalt can be useful for providing access for pedestrians, bicyclists, wheelchair users and cars. However, the paving over of millions of hectares of land and vegetation have contributed to numerous economic and environmental problems.
Depave—one of the community groups that is pioneering this movement—is focused on reclaiming over-paved spaces in Portland, Oregon. Bringing together staff and volunteers for what it describes as “constructive destruction”, the organization partners with host sites each year to demolish un- or under-used pavement, and instead design, fund, and install a range of permeable community spaces that include play-scapes, parks, and community gardens. According to their 2019 Impact Report, the group has depaved over 20,438 square metres over the past 12 years, collecting stormwater runoff from over 46,450 square metres of adjacent impervious areas. All together, their work has reduced annual stormwater runoff by 59,960.9 kilolitres.
While we may need sidewalks and roadways, we can minimize the pavement we use for driveways and parking areas, and thereby restore the natural environment. Ideally, we shouldn’t be paving over habitat and farmland to accommodate auto-centric development. Depaving can reverse the damage! By rethinking our built environment, we can create opportunities for water to seep into the ground during extreme rainwater events—and often sequester carbon and promote biodiversity in the process too.