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What is the Chemical and Microbial Content of Our Tap Waters?

Science Center Objects

Safe Drinking Water Act compliance addresses the safety of public-supply water systems. The composition of public-supply drinking water is generally only tested at the treatment plant, and not at the tap after traveling through the water distribution system. Only lead and copper are tested at a subset of residential and other taps. Testing of water in private wells is rare unless local health ordinances require minimal testing during property resale.

The safety of tap water and water from private water wells is the therefore the responsibility of the owner.

Our specialized teams of hydrologists, chemists, microbiologists, and geologists are working together in labs and at field sites across the U.S. with collaborators from the National Institute of Environmental Health Sciences, the U.S. Environmental Protection Agency, non governmental organizations, academia, and the drinking water industry to understand the chemical and microbial content of water at taps in our homes and offices, the origins of these contaminants, and how this information can be used to better protect public health?

    Idealized diagram of a public water supply's water distribution system

    Idealized diagram of a public water supply's water distribution system.

    (Credit: Paul M. Bradley, US Geological Survey. Public domain.)

    Questions We're Working On:

    • Can tap water expose us to chemical or microbial contaminants that pose public health hazards?
    • How do drinking water infrastructure, treatment, plumbing, and point-of-use filters remove or add contaminants?
    • Can our knowledge of geochemistry, hydrology, and microbiology be applied to help develop lower-cost methods that individual home or business owners can use to treat their tap waters?