 It's simply Splashtastic. Deep River Water Park is now open for another Splashtastic season of outdoor family fun. The wave pool, water slides, tube slides, two river rides, the dragon, and much more are all waiting for you. We're four and a half miles east of 565 on US 30 in northwest Indiana. See you there. Deep River Water Park, bring your family and your friends. Splashtacular fun for every age. A good time never ends.