Madison-based water park resort operator Great Wolf Resorts Inc. plans to sell first-mortgage debt, and use the sale proceeds to pay off debt on three of its properties. The debt being sold totals $225m that comes due in 2017, subject to market conditions, according to a Great Wolf statement. The company plans to use the proceeds to repay outstanding mortgage debt, totaling $212m, on resorts in Mason, Ohio; Williamsburg, Va.; and Grapevine, Texas. Any proceeds left will be used for general corporate purposes.