Water will eject from a tire at a tangent to the tire OD. If you lay a yardstick on the tire, with the longer end resting atop the fender rear edge, you'll get an idea of the max water ejection angle. Probably the middle of your back.
Of course, that assumes that you can find a puddle out there.
Rocks don't stick that well, especially with that tread pattern, and will eject early, to the rear...