Ordinances of noncharter code cities the qualified electors of which have elected to exercise the powers of initiative and referendum shall not go into effect before thirty days from the time of final passage and are subject to referendum during the interim except:

(1) Ordinances initiated by petition;

(2) Ordinances necessary for immediate preservation of public peace, health, and safety or for the support of city government and its existing public institutions which contain a statement of urgency and are passed by unanimous vote of the council;

(3) Ordinances providing for local improvement districts;

(4) Ordinances appropriating money;

(5) Ordinances providing for or approving collective bargaining;

(6) Ordinances providing for the compensation of or working conditions of city employees; and

(7) Ordinances authorizing or repealing the levy of taxes; which excepted ordinances shall go into effect as provided by the general law or by applicable sections of Title 35A RCW as now or hereafter amended.