Abstract: A system of conserving water using non-electrically operated, readily available plumbing equipment. The water to be saved with the system is water once heated which has cooled due to heat loss in a hot water line. This normally wasted cold water in the hot water line is often directed down the drain prior to dispensing of the hot water from a fixture. The system is adapted to divert the normally wasted cold water in the hot water line to a remotely positioned storage tank. The diverting process begins upon manual activation of a by-pass valve positioned slightly upstream of the hot water valve of a typical hot water dispensing fixture. The cold water to be saved is diverted by the manual by-pass valve through by-pass piping leading into the storage tank. The storage tank is also plumbed with piping to the water input piping of each toilet tank reservoir of the building.