Bonds and notes issued pursuant to this chapter and (a) secured solely by a pledge of revenues to be derived from sewerage system use charges or (b) guaranteed, in whole or in part, by state, federal or private grants of money shall not be subject to any statutory limitation, to the extent of such security or guarantee, on the indebtedness of the municipality and such bonds and notes when issued shall not be included in computing the aggregate indebtedness of the municipality in respect to and to the extent of any such limitation. Any provision of any special act inconsistent with the provisions of this section is repealed.