Some scientists believe we're living in a new epoch of history, the Anthropocene, defined by how drastically humans have altered the Earth with mining, roadways and other earthworks. Now, engineers are testing plastic roads that can be installed and removed incredibly quickly.
One recent entrant into this new business is the Dutch construction company, VolkerWessels, is collaborating with the city of Rotterdam to start prototyping plastic-built roads in a "street lab" provided by the city. It's extremely early days for the project — and we should take it with a massive grain of salt — but it's still an interesting proposal. The idea is to recycle plastic from oceans into a tough aggregate that could be poured and moulded into pre-fabricated "bricks" and installed on site quickly. As the The Guardian notes, prefab roads would go a long way towards curtailing the massive amount of pollution created by asphalt ("2% of all road transport emissions," the paper says).
The pieces would be hollow, allowing workers to run infrastructure through them like tunnels and replace these connections without digging up the road entirely. It would "also ideal for poorer soil," the company explains, adding that "this applies to at least half of the Netherlands," where cities sit on swampy or sandy land. They're not unlike lego roads — easy to snap together, remove, and alter. Most importantly, maybe, it collects all of the complex materials and systems that run through our streets into a single, protected layer.
VolkerWessels is actually far from the first company to have this idea, though. An Indian chemistry professor named Rajagopalan Vasudevan, who specialises in figuring out new ways to reuse old plastic, was profiled by Bloomberg recently for developing a way to turn recycled plastic into a polymer that can used to make asphalt instead of traditional bitumen. The roads are stronger, cheaper, and of course, greener. India has used it to build roads for years now.
Of course, those "plastic" streets are still traditional asphalt — a more realistic proposal than VolkerWessels', which would totally alter the way highways and streets are built from the beginning to the end and has years, even decades, of research and development ahead of it, if it survives.
But it's also indicative of an interesting shift towards designing infrastructure with an exit strategy; roads and bridges and other pieces of landscape-altering structure that are designed to be removed, as well as installed. No city lasts forever, and neither do roads. And after thousands of years of building them, it seems like engineers are beginning to think about how to make them easier to remove.