The purposes of this chapter are to provide for the preparation and carrying out of plans, for disaster and emergency services, the protection of persons and property within the city in the event of disaster, and to provide for the coordination of the disaster and emergency functions of the city with all other affected persons and agencies, both public and private. Any expenditures made in connection with such disaster or emergency services, including mutual aid activities, shall be deemed conclusively to be for the direct protection and benefit of the inhabitants and property in the city. (Prior code § 1510)