One way to reduce treated water demand is to substitute an alternate water supply for an existing demand. Using stored rainwater to irrigate plants is an example of this concept. This page offers information on various alternate water supply options like blow-down water, condensate water, graywater, package graywater recovery and treatment systems, rainwater harvesting, stormwater harvesting, and cisterns, and reverse osmosis discharge water as well as links to the latest research and information about this important topic.