You can use the indoor waterpark if you buy a day pass or if you stay at the hotel overnight. There are no season passes for the indoor water park. However if you are a theme park season pass holder and you become a member there are exclusive discounted pricing for certain days for use of the water park only.
I think they may have a pass for the indoor one but you can not use your regular park pass for the indoor one.
I think there is but I would call them as every year things can change.
I think you can use your season pass for both parks but to confirm please call them.
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