65 ILCS 5/11-141-4
Within 10 days after this ordinance has been passed, it shall be published at least once in one or more newspapers published in the municipality, or, if no newspaper is published therein, then in one or more newspapers with a general circulation within the municipality. In municipalities with less than 500 population in which no newspaper is published, publication may instead be made by posting a notice in 3 prominent places within the municipality.
If the ordinance specifies that the municipality has been directed by an order issued under the provisions of "An Act to establish a Sanitary Water Board and to control, prevent and abate pollution of the streams, lakes, ponds and other surface and underground waters in the State, and to repeal an Act named therein", approved July 12, 1951, as heretofore and hereafter amended, and the Environmental Protection Act, to abate its discharge of untreated or inadequately treated sewage, the ordinance authorizing the issuance of those revenue bonds shall be in effect immediately upon its adoption and publication, or posting, as provided in this section, notwithstanding any provision in this Code or any other law to the contrary.
In all other cases, if no petition is filed with the municipal clerk as hereinafter provided in this section, within 30 days after the publication or posting of the ordinance, the ordinance shall be in effect after the expiration of that 30 day period. In such cases the publication or posting of the ordinance shall be accompanied by a notice of (1) the specific number of voters required to sign a petition requesting the question of improving or extending or of construction or acquiring and improving and extending a sewerage system and of issuing revenue bonds to be submitted to the electors; (2) the time in which such petition must be filed; and (3) the date of the prospective referendum. The municipal clerk shall provide a petition form to any individual requesting one. But if within that 30 day period a petition is filed with the municipal clerk signed by electors of the municipality numbering 10% or more of the number of registered voters in the municipality, asking that the question of improving or extending or of construction or acquiring and improving and extending a sewerage system and of issuing revenue bonds to pay the cost thereof be submitted to the electors of the municipality, the municipal clerk of the municipality shall certify the question for submission at an election.
If a majority of the electors voting upon the question voted in favor thereof, the ordinance shall be in effect, but if a majority of the electors voting upon the questions are not in favor thereof, the ordinance shall not take effect.
65 ILCS 5/11-141-4