Reclaimed water is water that has been used more than once before it passes back into the natural water cycle. It is the result of the process of water reclamation, which converts municipal or industrial wastewater into water that can be reused for a variety of purposes. Reclaimed water is treated differently depending on its source and use, and how it gets delivered.

There are two types of water reuse: planned and unplanned. Unplanned water reuse refers to situations in which a source of water is substantially composed of previously-used water, such as when communities draw their water supplies from rivers that receive treated wastewater discharges from communities upstream. Planned water reuse, on the other hand, refers to water systems designed with the goal of beneficially reusing a recycled water supply. Examples of planned reuse include agricultural and landscape irrigation, industrial process water, and environmental restoration.

Reclaimed water can offer a viable and effective alternative where freshwater supplies are scarce. It is utilized to maintain or increase lake levels, restore wetlands, and restore river flows during hot weather and droughts, protecting biodiversity. Additionally, reclaimed water is utilized for street cleaning, irrigation of urban green spaces, and industrial processes.

Reclaimed water is classified according to the source from which it originated. Municipal reclaimed water is treated water that is primarily derived from permitted sewage treatment plants, while industrial reclaimed water is from a non-domestic or non-municipal source. Reclaimed water is safe and suitable for a purpose that would use other water resources, but reuse of untreated wastewater is prohibited.

In summary, reclaimed water is treated wastewater that is safe and suitable for a purpose that would use other water resources. It is used to maintain or increase lake levels, restore wetlands, and restore river flows during hot weather and droughts, protecting biodiversity. Reclaimed water is classified according to the source from which it originated, and it is utilized for a variety of purposes, including street cleaning, irrigation of urban green spaces, and industrial processes.