(2) No part of such taxes shall be levied and collected for the purpose of paying either principal or interest, or both, on any revenue bonds issued by the district.
(3) In the event of inadequacy of the revenues of the district to pay the costs of operation and maintenance thereof and the principal of and interest on the bonds of the district promptly as the bond principal and interest obligations respectively become due and payable, neither this limitation nor any other limitation in this chapter restricts or impairs the right of the district to levy ad valorem taxes against all property within the district taxable for its purposes in order to provide funds with which to pay the general obligation bond principal and interest when due.
(4) Any utility district created prior to June 14, 1941, may levy taxes as in this section provided for the same term and under the same conditions as would be applicable to districts organized after that date. [Amended by 1963 c.9 §5; 1991 c.459 §357]