Dual water systems feature two separate distribution systems that supply potable water through one distribution network and non-potable water through another. The two systems work independently of each other within the same service area. Using dual systems can boost public water supplies because they lessen the burden on drinking water systems because they do not have to provide water treated to drinking water standards for activities such as toilet flushing, firefighting, street cleaning, and irrigating ornamental gardens or lawns. In addition, dual water systems have the potential to save communities money because water can be used for more than one purpose thus reducing consumption of potable water. This Tech Brief discusses the dual-system concept.