I think the chances are very slim for this (cars splashing water on you, thereby causing hydrolock) is very rare. The only time I've ever gotten close to a hydrolock with my AEM CAI
was when I went through a touchless car wash. I didn't turn off the car, just left it in drive while on the brake. While the water was jetting on my front in, I felt the engine begin to bog. I assume it was from the tremendous amount of water being rushed into the area around the Intake
. After completion of the wash, I pulled out slowly, and eased around for a while and never felt any more bogging. So it seems to be ok.
If you are legitamately worried, when water is about to be splashed on your car, release the accelerator. This should close off the throttle body, thereby preventing water from being sucked in.