NOVELTY - An inner housing confined within the outer housing (16) has two engaging hubs and paddles held between the hubs non-rotatably coupled with the outer housing. The inner housing rotates within the outer housing around a centering rod. A manifold in the housing has a passageway that channels liquid flow to the filter. A second passageway channels the flow of filtered liquid to the UV dosing system. The flow of UV-exposed liquid may be channeled to a nozzle (14), which extrudes stream of liquid at relatively high velocity and induce rotation of hydro-generator.    USE - Serves as an electrical power source for the ultraviolet dosing system of a miniature residential or portable water treatment system. The hydro-power generation system may also be used for a plumbing fixture which includes lavatory related devices such as faucets, toilet flush mechanisms, sprayers, showers, sprinklers, fountains and any other devices and mechanisms used to control and channel the flow of liquids at pressures less than 1034 kPa. The system may also be used for electrically operated valves or electromechanical valves, other liquid treatment systems and other devices that require and electrical power source to operate.    ADVANTAGE - The miniature hydroelectric generation system is small enough to fit within the water treatment system. It operates with enough efficiency to produce sufficient power to operate the water treatment system. The single piece construction of the manifold avoids multiple hoses, fittings and connections and permits the watertight flow of liquid between the modules. The manufacturing efficiency, ease of maintenance and reliability are improved.    DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for the method of manufacturing a hydro-power generation system.    DESCRIPTION OF DRAWING(S) - The drawing shows a water treatment system coupled to the hydro-power generation system.    Hydropower generation system (12)    Nozzle (14)    Housing (16)    Impellers (18)    Housing outlet (20)