On or before September 15th each year the council shall levy by resolution the taxes necessary to meet the requirements for the ensuing calendar year. The city clerk shall transmit to the county auditor annually, not later than September 15th, a statement of all the taxes levied, and such taxes shall be collected and the payment thereof be enforced with and in like manner as state and county taxes. No tax shall be invalid by reason of any informality in the manner of levying the same, nor because the amount levied shall exceed the amount required to be raised for the special purposes for which the same is levied, but in that case the surplus shall go into the fund to which such tax belongs.