Except as otherwise provided in this Charter, ordinances providing for the exercise of any powers of government granted by the Constitution of the State of Ohio or delegated by the Ohio General Assembly to the City may be proposed and submitted to the electors of the City by initiative petition. Except as otherwise provided in this Charter, the effective date of an ordinance passed by the City Council may be suspended until such ordinance is approved by the electors of the City by referendum petition. If the Council is required to pass more than one ordinance to complete and pay for any public improvement, the referendum shall apply only to the first ordinance to be passed and not to any subsequent ordinance in the series relating thereto.