Abstract: A water supply system in accordance with the invention includes pumping in which there is a mechanical co-dependency between the generations of liquid-draw pressure and filtration-drive pressure, but a hydraulic dependency of the application of the filtration-drive pressure upon release of water from the liquid-draw pressure. In one preferred embodiment, the system is enabled by a retrofit assembly in which a second, filtration-drive pump is mechanically connected to the pump handle of a water intake pump. The retrofit assembly may include multiple arms and hinge points for coupling the second pump to the pump handle, as well as a flow path from the output of the water intake pump to the input of the second pump and a flow path from the second pump to a filtration system. The flow path between the two pumps typically includes an unfiltered water outlet.

Abstract: An apparatus and methods for producing purified drinking water are disclosed. A hand pump is used in a closed system to generate pressure sufficient to pass the untreated water through a system of filters and a reverse osmosis membrane. The system preferably includes an ultrafiltration filter. The resulting water is substantially pure, being free of bacteria and having a significant amount of minerals and salts removed to make it safe for drinking. The system can produce enough potable water to supply the daily needs for a small village.

Abstract: An apparatus for producing purified drinking water. The apparatus comprises a container top including an ultrafiltration insert. The container top attaches to the opening of a liquid holding container, such that liquid from the container passes through a filter. The device includes a mechanism for back flushing or cleaning the filter. The resulting water is substantially pure, being free of bacteria, to make it safe for drinking.