A Raw Water Intake is a structure or system designed to divert and collect raw water – that is untreated water found naturally in the environment - from rivers, lakes, groundwater or the sea.  A Raw Water Intake is used to supply water to facilities for various uses including drinking water supply, industrial use, agriculture uses or as cooling water.

As well as a structure or method of collecting the water a Raw Water Intake may additionally have a storage area to hold water before it is treated and used, a pumping station or similar to move the water if other than by gravity, and some initial means of screening the water ahead of any further required treatment or filtration.

Raw water has not undergone any treatment to remove impurities and contaminants that it usually contains. Raw water is rarely used without first undergoing some screening or treatment to reduce or remove any debris, particulate or other contaminants that may be in the water.

Water taken out of the environment for whatever purpose will usually need to be treated before use. Intake screening is the first process, and more often than not is in fact a pre-filtration ahead of other processes to further clean up the water.

What needs to be done to the water will depend on the water quality, the intended use(s) for the water, and whether there is a need to protect wildlife.  The reasons for screening will vary with application, but these are the main concerns:

• Maintaining Water Quality.   Screening is used to ensure a reliable and efficient water supply, drawing the best quality water available from the water source
• Protecting Equipment. Screening removes large debris that could damage or clog pumps, pipes, irrigation equipment and other machinery in industrial processes
• Protection of Aquatic Life. Screening is often required to minimize the impact on fish and other aquatic life.