Whenever, in the opinion of the City Manager, there is an actual or threatened local emergency such as riot, fire, flood, excessive snowfall, other acts of God, common disaster or acts of the enemy, the City Manager may require the removal of motor vehicles parked upon the affected streets of the City. The City Manager shall inform the public of the aforementioned conditions through reasonable and usual methods of communication, If the owner or operator of a vehicle does not remove it within a reasonable time, the vehicle may be removed by the Police Department.