An emergency utility backup system, for a building normally supplied with culinary water, electric power and natural gas by public utilities, includes at least one water storage reservoir having an upper input coupled to a public water utility main line; an electric generator powered by an internal combustion engine; and an electric air compressor having a compressed air storage tank which provides elevated air pressure to the water storage reservoir(s) in the event that water pressure from the public water utility main line fails. The electric air compressor is operable from power supplied by either a public electric utility or said electric generator. The emergency utility backup system may also include a tank for storing a liquid hydrocarbon fuel that may be utilized for both the electric generator and a heating system for the building. Electric power to the building is supplied either from an electric utility source through circuit breakers located within a main circuit breaker panel, of from the electric generator through breakers in a load distribution and transfer switch box.