Waterloo / Lost Island Waterpark KOA Resort 4550 Hess RdWaterloo, IA, 50701 View Phone 319-233-3485 Fax: 319-234-0810 Toll Free: 800-562-2483 4550 Hess RdWaterloo, IA 50701 View Website Experience & Reliability About Connect with this Business: Reservation Send to My Email Send to My Phone Print this Page