Grammar Question

Reads alright. Other punctuation is possible but the current one is not wrong, so... Is there anything in particular that's bugging you about it?

not sure about the verb form you've chosen: "would hover." It suggests that something is preventing that traffic from hovering, and it would hover if only that something were removed.

Are you perhaps saying that hovering is what that traffic habitually or routinely does? In that case, you'd say something like

the traffic on this route hovered a meter or so above the synthetic road surface

It reads OK insofar as it has no obvious errors, but out-of-context it is meaningless to me. What point are you trying to make, if any?

That there aren't any cars on the road right now is clear enough, but the next section makes a play on words to tell me the road surface has never been used at all.

Are there still cars hurtling along above the surface?