I admit it. I had never been to a water park. Until I took one of our boys to Splashdown Beach in nearby Fishkill, NY. Fishkill is in the Hudson Valley up 684 and across 84 West towards the Hudson and about one hour from Rye. Directions here.
Run by the same family that owns Rocking Horse Ranch (a family resort that gets rave reviews further up in Highland, NY), Splashdown was a mega-hit with our five year old. It is super clean with lots of lifeguards and lots to do including a wave pool, water slides (small and large for various ages), a lazy river, and so many other pools I can’t count. There is also mini-golf and an indoor arcade that includes some old fashioned skeet ball. A friend of the owner was there the entire day blowing up balloons shaped like various animals and entertaining all the kids (he was a pied piper of balloons).
The park is not too big and not too small and is perfect for families with kids up to maybe early teens. Kids are $18 and adults are $23 for the day and for the most part, this pays for almost all the rides and attractions. We went on a sunny Friday and never waited more than 2 or 3 minutes for a ride and no pools were overcrowded.
Enjoy and have fun!