mneblett
#32806
They're grooved as an anti-hydroplaning measure -- the grooves give the water a place to go. You can still drive too fast for the amount of water present, but the grooves at least delay the on-set of hydroplaning, and their edges can give the tires something to bite on in response to a steering input.In general, pavements are grooved to provide a smoother ride for cars and to correct irregularities due to contractor errors in paving.