(1) (a) Every district and municipality fixing and collecting rates or charges, or both, as provided in section 32-4-510 (1)(l) and elsewhere in this part 5, or otherwise, is, in supplementation of such powers, authorized to fix and collect rents, rates, fees, tolls, and other charges, in this part 5 sometimes referred to as "service charges", for direct or indirect connection with, or the use or services of, a sewage disposal system or sewer system, respectively, including, without limiting the generality of the foregoing, minimum charges and charges for the availability of service.

(b) Such service charges may be charged to and collected in advance or otherwise by a district from any municipality within the district and by any municipality from any person contracting for such connection or use or services or from the owner or occupant, or both of them, of any real property which directly or indirectly is or has been or will be connected with the sewer system or from which or on which originates or has originated sewage or other wastes which directly or indirectly have entered or may enter the sewage disposal system and sewer system, and the municipality or owner, or occupant, of any such real property shall be liable for and shall pay such service charges to the district or municipality fixing the service charges at the time when and place where such service charges are due and payable.

(c) Such service charges of any district may accrue from any date on which its board reasonably estimates, in any resolution authorizing the issuance of any securities or other instrument appertaining thereto or in any contract with any municipality, that any sewage disposal system or project being acquired or improved and equipped will be available for service or use.

(2) (a) Such rents, rates, fees, tolls, and other charges, being in the nature of use or service charges, shall, as nearly as the district or municipality fixing the service charges shall deem practicable and equitable, be reasonable, and shall be uniform throughout the district or municipality for the same type, class, and amount of use or service of the sewage disposal system or sewer system, and may be based or computed either: On measurements of sewage flow devices duly provided and maintained by the district or by the municipality or any user as approved by the district or municipality fixing such charges, and analyses of sewage samples procured and made by or in a manner approved by the district; or on the consumption of water in or on or in connection with the municipality or real property, making due allowance for commercial use of water and infiltration of groundwater and discharge of surface run-off to the sewer system; or on the number and kind of water outlets on or in connection with the municipality or real property, or on the number and kind of plumbing or sewage fixtures or facilities in or on or in connection with the municipality or real property; or on the number of persons residing or working in or on or otherwise connected or identified with the municipality or real property, or on the capacity of the improvements in or on or connected with the municipality or real property; or upon the availability of service or readiness to serve by the system; or on any other factors determining the type, class, and amount of use or service of the sewage disposal system or sewer system; or on any combination of any such factors, and may give weight to the characteristics of the sewage and other wastes and any other special matter affecting the cost of treatment and disposal thereof, including chlorine demand, biochemical oxygen demand, concentration of solids, and chemical composition.

(b) Reasonable penalties may be fixed for any delinquencies, including, without limiting the generality of the foregoing, interest on delinquent service charges from any date due at a rate of not exceeding one percent per month, or fraction thereof, reasonable attorneys' fees, and other costs of collection.

(3) The district or municipality fixing the service charges shall prescribe and, from time to time, when necessary revise a schedule of such service charges, which shall comply with the terms of any contract of the district or municipality fixing the service charges, and in any event shall be such that the revenues from the service charges of the district or municipality will at all times be adequate, except to the extent that the proceeds of any general ad valorem tax or other moneys are available and used, after an allowance is made for delinquencies accrued and reasonably estimated to accrue by the board or governing body fixing the service charges, for the payment of such service charges, whether resulting from any delinquency of any municipality, other public body, or other person, or from any other cause:

(a) To pay all expenses of operation and maintenance of the sewage disposal system or sewer system, including reserves, insurance, and improvements;

(b) To pay punctually the principal of and interest on any securities payable from revenues of the sewage disposal system or sewer system and issued or to be issued by the district or municipality fixing the service charges;

(c) To maintain such reserves or sinking funds therefor; and

(d) For the payment of any expenses incidental to any sewage disposal system or sewer system or any project authorized in this part 5, any contingencies, acquisitions, improvements, and equipment, and any other cost, as may be required by the terms of any contract of, or as may be deemed necessary or desirable by, the district or municipality fixing the service charges.

(4) Said schedule shall thus be prescribed and from time to time revised by the district or municipality. A public hearing thereon may be, but is not required to be, held by the district or municipality at least seven days after such published notice is given, as the district or municipality may determine to be reasonable. The district or municipality shall fix and determine the times when and the places where such service charges shall be due and payable and may require that such service charges shall be paid in advance for a period of not more than one year. A copy of such schedule of service charges in effect shall at all times be kept on file at the principal office of the district or municipality fixing the service charges and shall at all reasonable times be open to public inspection.

(5) The legislature has determined and declared that the obligations arising from time to time of any municipality or person to pay service charges fixed in connection with any sewage disposal system or sewer system shall constitute general obligations of the municipality or person charged with their payment; but as such obligations accrue for current services and benefits from and use of any such system, the obligations shall not constitute an indebtedness of the municipality or other public body within the meaning of any constitutional, charter, or statutory limitation or other provision restricting the incurrence of any debt.

(6) No board, agency, bureau, commission, or official, other than the board of the district or the governing body of the municipality fixing the service charges, has authority to fix, prescribe, levy, modify, supervise, or regulate the making of service charges, nor to prescribe, supervise, or regulate the performance of services appertaining to a sewage disposal system or sewer system, as authorized in this part 5; but this subsection (6) shall not be construed to be a limitation on the contracting powers of the board of any district or the governing body of any municipality within the district.