The last two times that I have ridden I have noticed a light spray of water hitting the under side of the train at least on the back cars while it was parked in the station for loading...
Yes, it's for cooling the wheels. The water sprayers only turn on when the train is in the station...
And what's super awesome is when those water nozzles sometimes get pointed upwards, arching their spray directly into the cars of the train.
Unlike i305, I (very sadly) cannot sprint at 90 mph. But one visit earlier this season, I don't think the coaster realized that - where during an unusually long dispatch cycle - decided to completely drench my lower body; perhaps thinking I too needed some 'cooling of my wheels'.
So where i305 loves to deliver some of the most extreme intensity ever to be found on a coaster... sometimes, just sometimes, you get an extra added bonus of water elements