Any person wishing to receive credit for water line leaks due to breakage, whereupon water leakage has occurred from said water line, that does not impact the sanitary sewer system must submit a formal request for credit with documentation, to include an invoice for the repair from a licensed plumbing contractor or, if the property owner makes the repairs, a statement reflecting this and an invoice of the material used for the repair must be submitted to the Finance Department.  The City's sewer department will verify that no impact to the sewer system occurred as a result of the leak.  The credit issued shall be for excess water consumption above the annual average for the prior 12 months, but in no way shall the sewer billing for the period in which the leak occurred be less than the consumption during the same period the previous year.