> Finally, people have seen what recent innovation in concrete pavements can bring, with this permeable concrete that instantly absorbs thousands of gallon of water [3].

While certainly impressive, this leaves the question: Where the f..k is all that water going?

Typically, at least in cities here, the water goes off into drains, and then into a water treatment plant which prevents nasty stuff like oil or other car-originated toxins from compromising the ground below.

Something like this system, if not connected to drainage piping, would basically let all the liquid waste seep into the ground - compared to a sealed asphalt/concrete ground, where firefighters can spread sand or other oil binders to prevent widespread release into the environment.