Simplify the following text for a Grade 8 native English-speaking person.
Original: Indoor waterparks in Wisconsin Dells debuted in 1994 after the Polynesian Resort Hotel built the first one in the U.S. .
Simplified: Indoor waterparks in Wisconsin Dells started in 1994 after the Polynesian Resort Hotel built the first one in the U.S. Mt. Olympus Theme and Water Park ( formerly Family Land ) is another huge water park in The Dells .