A self-contained hydroelectricity generating system to produce an amount of usable electrical energy has primary and secondary cisterns containing a motive fluid. A hydro-expeditor tower assembly includes a plurality of spiral hydro-expeditor towers each disposed in fluid communication with the primary cistern, a portion of the motive fluid flows from the primary cistern into and through each of the hydro-expeditor towers increasing the velocity thereof. A hydroelectric generator assembly has a plurality of hydroelectric generator units each disposed in fluid communication with a corresponding spiral hydro-expeditor tower, the motive fluid discharged from each of the spiral hydro-expeditor towers contacts the turbine of a corresponding hydroelectric generator unit resulting in generation of the amount of usable electrical energy. The motive fluid from the hydroelectric generator units is discharged into the secondary cistern and is then transferred to the primary cistern for reuse through the system.