The City Manager shall appoint, subject to the approval of the City Council, one of the other officers or department heads of the City to serve as manager pro tempore during any temporary absence or disability of the City Manager. In case of the absence or disability of the City Manager and his failure to so appoint a manager pro tempore, the City Council may designate some qualified City employee to perform the duties of the City Manager during the period of absence or disability of said City Manager, subject, however, to said person furnishing a corporate surety bond conditioned upon faithful performance of the duties required to be performed as set forth in SMC 2.12.040.