Potholes, water, and street damage

One thing that amazed me once I noticed it was how fast roads fall part if they have a decent-sized pothole filled with water.  Each car that drives through jets a little water out as their tire fills the pothole, and the water jet carries some of the gravel that makes up the road asphalt.  If you look at this picture, you can see all the gravel accumulating next to the curb and sprayed up onto the cycle track.  I think the presence of the pothole also degrades the pavement nearby; I can’t tell if it’s a lack of support from the side, or if water is getting access to the roadbed and making it less firm.  Either way, damage accumulates fast.

 I’ve been completely unable to find any research or analysis of how this damage might depend on car speed; greater speed is certainly a cause of more vigorous splashing to the side.  It seems like reducing speed might also reduce the rate of pothole growth, but apparently this is not studied, not published, or not findable.  As near as I can tell with search engines, the internet consensus is that potholes arise spontaneously and are inflicted on cars, not vice-versa.