@Terrificli -- I am not sure that I agree with you. How much safer is permeable pavement than conventional pavement material? Is it safer at all? Are there any studies that answer that question one way or the other? I don't know if any such studies actually exist.
But here is what I do know. Let's say you take a rain storm. The most dangerous time to travel on a conventional road during a storm is right after it starts. When a street gets wet, that is when oil and crud comes to the surface and the street is the slickest. After that period has passed and oil is washed away, traction is actually pretty good. That is doubly tree in this day and age when sure footed, front wheel drive vehicles are common.
What I don't know is if the permeable pavement is so much safer that the added expense is worth it. If we were truly talking about saving lives and such, wouldn't there be more of a demand for this paving material to be put to good use?