Ind. Code § 8-1-11.1-12

Sec. 12. The current receipts and all other moneys derived from the operation of any such utility property shall be expended by said board of directors upon vouchers in a form to be determined by them, and any such funds shall be deposited in such bank or banks as may be determined by said board to the credit of said board of directors for utilities, and any interest earned on any such deposits shall be added to the principal thereof. No appropriation in any form shall be necessary for the expenditure of any of such current income or for the expenditure of the proceeds of any sale of bonds, or of any other obligations, as authorized under this chapter, but all funds arising under this chapter shall be deemed appropriated for the respective purposes set forth in this chapter and shall be under the control of the board of directors for utilities as provided in this chapter, and said board of directors shall have full, complete and exclusive authority to expend such funds for the purposes set forth in this chapter.