Imagine driving on a perfectly flat road that has no potholes – and which can be recycled when you’re done with it. Such a road is coming to Los Angeles after Mayor Eric Garcetti decided to work with road tech company TechniSoil Industrial on replacing the city’s bus lanes and deteriorating asphalt.
TechniSoil uses plastic waste, otherwise destined for landfill or our oceans, as a replacement for bitumen – the black, oil-derived sludge that holds traditional roads together. The new surface makes use of all the asphalt that has already been laid, meaning that the roads are in effect recycled rather than replaced. This saves the tremendous carbon resources required to bring in new and take away old asphalt each time. TechniSoil claims its roads are between eight and 13 times more durable in lab tests, and it anticipates a minimum lifecycle double that of a regular road.
TechniSoil uses approximately 2,300kg of recycled PET plastic per 1.5km two-way road, which equates to around 395,000 plastic bottles, but CEO Sean Weaver hopes to double this content by 2022. “We’re turning something meaningless into the single most valuable piece of infrastructure,” he says. “We can consume all of the world’s waste plastic into our system, and we can do that within the next eight years. There is no other technology that can do that.”
The idea of adding waste plastic into roads dates back to 2001 when Rajagopalan Vasudevan, an Indian chemistry professor, recognised plastic’s binding qualities and pioneered a plastic-bitumen road-laying technique across India. With newer technologies, plastic roads can meet higher road standards, and the idea is spreading globally.
Shell and Total enhance their roads with newly-produced polymers, but several companies are seeking to use waste plastics for the same purpose. Besides TechniSoil, there’s Dow Chemical, which has worked with local governments across Indonesia, India, and Thailand since 2017; and Scottish company MacRebur, which makes road products that replace part of the bitumen with waste plastic crumbs. Dutch company PlasticRoad makes roads entirely of waste plastic, which will now be taken to market after successful pilots in the cities of Zwolle and Giethoorn.
One concern is whether these roads shed microplastics. MacRebur and TechniSoil dismiss this on the basis that they’re turning the plastic into its original oil-based state, but environmentalists encourage caution. “Even if the roads are more resilient, you would assume that, especially if they are made completely from waste plastic, they would erode to some extent and that would contribute to a problem they’re supposed to be solving,” Libby Peake, head of resource policy at Green Alliance, says.
LA’s commitment could be a watershed moment. “The roads of the future are going to be perpetual roads,” Weaver says. “If the agency, meaning the city or the state, gets better value for their dollar, and the user gets better value for their tax dollar, then you’re not going to be able to stop it.”