River Country was quite old, as far as water parks go, and they build two modern water parks to replace it. It was open seasonally for years, and then less and less as guests consistently chose to visit one of the newer water parks instead. It must cost a large amount of money to maintain the equipment for a water park, especially one that is so old, so it must not make much sense to spend all that money for just a few weeks per year when they'd need to have had the park open.