(1)    A municipality, in addition to any other authority to borrow money and issue its municipal obligations, may borrow money and issue its public improvement bonds to finance the cost of construction or acquisition, including site acquisition, of any revenue-producing public improvement of the municipality. In this section, unless the context or subject matter otherwise requires:

      (a)    “Debt service” means the amount of principal, interest and premium due and payable with respect to public improvement bonds.

      (b)    “Deficiency” means the amount by which debt service required to be paid in a calendar year exceeds the amount of revenues estimated to be derived from the ownership and operation of the public improvement for the calendar year, after first subtracting from the estimated revenues the estimated cost of paying the expenses of operating and maintaining the public improvement for the calendar year.

      (c)    “Municipality” means a county, sanitary district, public inland lake protection and rehabilitation district, town, city or village.

      (d)    “Public improvement” means any public improvement which a municipality may lawfully own and operate from which the municipality expects to derive revenues.

   (2)   The governing body of the municipality proposing to issue public improvement bonds shall adopt a resolution authorizing their issuance. The resolution shall set forth the amount of bonds authorized, or a sum not to exceed a stated amount, and the purpose for which the bonds are to be issued. The resolution shall prescribe the terms, form and contents of the bonds and other matters that the governing body considers necessary or advisable. The bonds may be in any denomination of not less than $1,000, shall bear interest payable annually or semiannually, shall be payable not later than 20 years from the date of the bonds, at times and places that the governing body determines, and may be subject to redemption prior to maturity on terms and conditions that the governing body determines. The bonds may be issued either payable to bearer with interest coupons attached to the bonds or may be registered under s. 67.09. The bonds may be sold at public competitive sale or by private negotiation. Sections 67.08 and 67.10 apply to public improvement bonds, except insofar as they are in conflict with this section, in which case this section controls.

   (2m)   

      (a)    A resolution, adopted under sub. (2) by the governing body of a municipality, need not be submitted to the electors of the municipality for approval, unless within 30 days after the resolution is adopted there is filed with the clerk of the municipality a petition, conforming to the requirements of s. 8.40 and requesting a referendum on the resolution, signed by electors numbering at least 10 percent of the votes cast in the municipality for governor at the last general election. A resolution, adopted under sub. (2), may be submitted by the governing body of the municipality to the electors without waiting for the filing of a petition.

      (b)    If a referendum is to be held on a resolution, the municipal governing body shall file the resolution as provided in s. 8.37 and shall direct the municipal clerk to call a special election for the purpose of submitting the resolution to the electors for a referendum on approval or rejection. In lieu of a special election, the municipal governing body may specify that the election be held at the next succeeding spring primary or election or partisan primary or general election.

      (c)    The municipal clerk shall publish a class 2 notice, under ch. 985, containing a statement of the purpose of the referendum, giving the amount of the bonds proposed to be issued and the purpose for which they will be issued, and stating the time and places of holding the election and the hours during which the polls will be open.

      (d)    The referendum shall be held and conducted and the votes cast shall be canvassed as at regular municipal elections and the results certified to the municipal clerk. A majority of all votes cast in the municipality decides the question.

   (3)   The reasonable cost and value of any services rendered by the public improvement to the municipality shall be charged against the municipality and shall be paid by it in monthly installments.

   (4)   

      (a)    Gross revenues derived from the ownership and operation of the public improvement shall be first pledged to debt service on issued public improvement bonds. When in excess of debt service, the revenues are subject to all of the following requirements set by resolution or ordinance of the governing body fixing:

         1.    The proportion of revenues of the public improvement necessary for the reasonable and proper operation and maintenance of the public improvement.

         2.    The proportion of revenues necessary for the payment of debt service on the public improvement bonds. The revenues shall be paid into a special fund in the treasury of the municipality known as the “Public Improvement Bond Account”.

      (b)    At any time after one year’s operation, the governing body may recompute the proportion of revenues assignable under par. (a) based upon experience of operation.

      (c)    All funds on deposit in a public improvement bond account, which are not immediately required for the purposes specified in this section, shall be invested in accordance with s. 66.0605.

   (5)   Annually, on or before August 1 the officer or department of the municipality responsible for the operation of the public improvement shall file with the governing body, or its designated representative, a detailed statement setting forth the amount of the debt service on the public improvement bonds issued for the public improvement for the succeeding calendar year and an estimate for that year of the total revenues to be derived from the ownership and operation of the public improvement and the total cost of operating and maintaining the public improvement.

   (6)   

      (a)    If it is determined that there will be a deficiency for the ensuing calendar year, the municipality shall make up the deficiency, but the obligation to do so is limited to a sum which does not cause the municipality to exceed its municipal debt limits. The deficiency may be made up by the municipality from any available revenues, including a tax levy. The amount contributed by the municipality shall be deposited in the public improvement bond account and applied to the payment of debt service. Taxes levied under this paragraph are not subject to statutory limitations of rate or amount.

      (b)    The amount of any deficiency determined under par. (a) for the ensuing calendar year shall be related to the total debt service for that year. The ratio determines the outstanding indebtedness of the issue to be reflected as part of the municipality’s indebtedness for the year.

   (7)   If revenue bonds have been issued by a municipality pursuant to law and an ordinance authorizing their issuance without limitation as to amount has been enacted by the governing body of the municipality, public improvement bonds may be issued under the ordinance with the same effect as though they were revenue bonds. The bonds are public improvement bonds and this section applies to the bonds, except that nothing contained in this subsection shall impair the contract between the municipality and the holders of outstanding revenue bonds. Liens created in favor of any outstanding revenue bonds issued under the ordinance apply to public improvement bonds issued under this subsection. The public improvement bonds are payable on a parity with the revenue bonds issued under the ordinance if the public improvement bonds are issued in compliance with the requirements of the ordinance for the issuance of parity bonds under the ordinance.