Wikipedia
Raw water is natural water found in the environment and has not been treated, nor have any minerals, ions, particles or living organisms removed. Raw water includes rainwater, ground water, water from infiltration wells, and water from bodies like lakes and rivers. The characteristics of raw water include physical ones, such as taste, temperature, or turbidity, chemical ones, such as hardness, acidity/ alkalinity, and ion content, and biological ones, such as organism presences. These characteristics can vary greatly depending on environmental conditions. Pollution can also effect raw water content.
Without treatment, raw water can be used for farming, construction or cleaning purposes. Farmers use it for watering their crops or give to livestock to drink, storing it in man-made lakes or reservoirs for long periods of time. Construction industries can use raw water for making cement or for damping down unsealed roads to prevent dust rising. Raw water can also be used for flushing toilets and washing cars, as well as any other purpose that do not require it to be consumed by humans. Water in this form is considered raw, as opposed to water which has been treated before consumption, such as drinking water or water which has been used in an industrial process, such as waste water. Contaminants usually make raw water unsafe for drinking by humans without treatment. However, millions of people in developing countries rely on untreated raw water for their water supply, sometimes purifying it by boiling.
Raw water flushing is a method of water conservation where raw water is used for flush toilets.