Revenues derived from the operation of any such swimming pools and golf courses financed in whole or in part by revenue bonds authorized by this act shall be paid into the treasury of the board of park commissioners and kept in a separate fund and shall not be used except for the purpose of paying the cost of operation, maintenance and improvement of such swimming pools and golf courses, providing an adequate depreciation fund and paying the principal of and the interest upon the revenue bonds issued under the act.
K.S.A. 13-1397