Does a season pass for the park include the water park as well? Or do you need to purchase a seperate season pass for the water park?

The season pass includes the water park, Fright Fest and Holiday in the Park. For Fright Fest and Holiday in the Park, if you want to go into the haunted houses or make s'mores those activities cost extra. If you plan on going at least twice year, it's definitely worth it though!!

I believe so

I am pretty sure the season pass works for the water park

A season pass includes the water park

All included