An article in Monday's Washington Post proposed that the plastic recycling problem could be solved by using the recycled plastic to make roads.
This is a quintessentially bad idea. It threatens to become a prime example of how today's solutions can become tomorrow's problems if you don't think it through.
For this to make a difference, it would have to go to scale, with massive numbers of roads being made of recycled plastic. If it didn't go to scale, it would become a boutique band-aid, allowing us to feel good about a faux solution but not really solving anything.
Here's tomorrow's problem if this gets implemented: Roads degrade because they get abraded by vehicular traffic. That becomes massive amounts of micro and nano plastic particles… plastic dust. Storm run-off would carry it into the waste water system or directly into surface waters.
Air currents would transport it in the wind. Sooner or later a lot of it would wind up in the oceans. And ultimately in our poop. It would become even more of a problem than what we have today.
Exactly how much of a problem would depend upon what mix of polymers were used and what additives might be in the plastics, as that would determine the particles' toxicity.