(1) In case the board of directors deems it necessary and expedient for such metropolitan utilities district to vote mortgage or revenue bonds for the construction, extension, or improvement of a water plant or any other public utility under its control or for any other purpose, to the end of supplying the district with water or other service for domestic, mechanical, public, or other purposes, the board may determine the amount of such bonds, when principal and interest is payable, and the rate of interest and may issue the bonds when voted. The board of directors shall submit a proposition to vote such bonds to the registered voters of the metropolitan utilities district at an election called by the board for such purpose, or at any regular election, notice of which has been given for at least ten days in one or more daily papers published in the district. If a majority of the votes cast upon such proposition is in favor of the issuance of such bonds, the board of directors may issue and sell such bonds in the manner as the board shall determine.
(2) In addition to the power provided in subsection (1) of this section as to issuance of bonds, and notwithstanding such provisions requiring a vote of the registered voters, and in addition to the limited power to borrow heretofore vested in any such district, the board of directors of such district without a vote of the registered voters and at their own discretion (a) may borrow, to be used solely for the purpose of extensions, improvements, additions, and capital investments, such sum as the board of directors by resolution determines to be needed for such purposes and (b) in the exercise of such additional power may issue warrants, notes, debentures, revenue bonds, or refunding obligations of the same classes, each of which shall be payable solely from the revenue of the district. The obligations issued by the district without a vote of the registered voters are hereby declared to be negotiable instruments, and such instruments and the interest paid thereon shall be exempt from any and all forms of taxation.
(3) The district may (a) refund all or any part of the obligations issued by the district without a vote of the registered voters by exchange or other means through the issuance of any of such forms of obligation at any time and in an amount equal to or exceeding the original amount, (b) invest the proceeds of refunding obligations for a temporary period until they are needed for the purpose of retirement of other obligations, (c) covenant as to rates, (d) create and provide for reserves or amortization funds, and (e) covenant as to the limitation of the creation of further indebtedness. All such evidences of indebtedness issued by the district without a vote of the registered voters shall be offered upon such terms and in such manner as the board determines. The same power to covenant and to provide funds shall also exist in the case of obligations authorized by the registered voters. The board of directors of any such district in the exercise of any of the borrowing powers, with or without a vote of the registered voters provided for in this section, may appoint as agents of such district corporations doing business within or without the State of Nebraska to act for it in receiving, redeeming, and paying for any of the securities so issued.