Water service shall be provided to any customer located outside the corporate limits of the City which the City has agreed to serve at rates one hundred fifty percent (150%) of the rates provided in Section 92.02. No such customer, however, will be served unless the customer shall have signed a service contract agreeing to be bound by the ordinances, rules and regulations applying to water service established by the Council.
(Code of Iowa, Sec. 364.4 & 384.84)