Tap water

Tap water, also known as running water, municipal water, or potable water, is water supplied to a tap (faucet) inside a building or dwelling from a public water supply system. It is generally treated to meet drinking water quality standards before distribution to consumers.

Source and Treatment:

The source of tap water varies depending on location, but commonly includes surface water (rivers, lakes, reservoirs) and groundwater (aquifers). Raw water from these sources undergoes a multi-stage treatment process to remove contaminants. Common treatment methods include:

• Coagulation and Flocculation: Chemicals are added to the water to clump together dirt and other particles, forming larger particles called floc.

• Sedimentation: The floc settles to the bottom of the treatment tank.

• Filtration: Water passes through filters of varying composition (sand, gravel, charcoal) to remove remaining particles and impurities.

• Disinfection: Disinfectants, such as chlorine, chloramine, or ultraviolet (UV) light, are used to kill or inactivate harmful microorganisms like bacteria, viruses, and parasites.

• Fluoridation (Optional): In some regions, fluoride is added to the water to help prevent tooth decay.

Quality and Regulations:

Tap water quality is regulated by governmental agencies, such as the Environmental Protection Agency (EPA) in the United States and similar organizations in other countries. These agencies set standards for permissible levels of various contaminants in drinking water to ensure public health. Regular testing and monitoring are conducted to verify compliance with these standards. However, the specific standards and the chemicals monitored may vary by jurisdiction.

Consumption and Concerns:

Tap water is a convenient and often cost-effective source of drinking water. However, some people may prefer bottled water or filtered water due to concerns about taste, odor, or the presence of certain contaminants. Potential contaminants can include lead (from old pipes), disinfection byproducts, and per- and polyfluoroalkyl substances (PFAS). Home water filters can be used to further improve the taste or remove specific contaminants.

Alternative Names:

• Running water
• Municipal water
• Potable water
• Drinking water (although "drinking water" can also refer to other sources)