Sec. 8. Subject to section 6(f) of this chapter, in the case of a water utility that is a municipally owned utility, upon the commission's approval of the water utility's plan under section 6 of this chapter, the water utility may include in the water utility's rates the costs for customer lead service line improvements that:
(1) are made, or are to be made, by the water utility;
(2) do not increase revenues by connecting to new customers, even though the plant or equipment may provide the water utility with available capacity greater than the available capacity provided to the customer before the line improvements;
(3) are or will be an extension or replacement consistent with section 9 of this chapter; and
(4) were not included on the water utility's balance sheet as plant in service in the water utility's most recent general rate case.