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Drinking Water Treatability Database (TDB)

Information on treatment processes for controlling contaminants

EPA's Drinking Water Treatability Database (TBD) is an easy to use tool that provides referenced information on the control of contaminants in drinking water. It was designed for use by utilities, first responders to spills or emergencies, regulatory agencies, consultants and technical assistance providers, treatment process designers, and researchers.

Information in the TDB is gathered from thousands of literature sources and assembled on one site. Information is available for more than 30 treatment processes and over 90 regulated and unregulated contaminants, including 22 PFAS chemicals.

Overview and Capabilities

Glass being filled with waterDrinking Water Treatability Database  (Home page)

Treatment and contaminants information in the TDB is gathered from thousands of literature sources focused on bench-, pilot-, and full-scale studies of surface water, groundwater, and laboratory water. The literature comes from peer-reviewed journals and conferences, other conferences and symposia, research reports, theses, and dissertations. Costs are not presented. However, the data pages indicate if a reference contains cost information and if a reference describes or cites the analytic method used to measure the contaminant.

Contaminants: The TDB includes chemical, microbial, and radiological contaminants that are regulated in drinking water, on the Contaminant Candidate List (CCL), of water security interest, of pesticide registration interest, and endocrine disruptors and pharmaceuticals. Because control strategies for disinfection byproducts (DBPs) are different than contaminants present in source waters, DBPs are not included in the TDB. Information on contaminants includes parameters, such as solubility, vapor pressure, Henry's Law constant; microbial parameters, such as size and shape; and fate and transport parameters that may be useful in assessing the contaminant's presence in source waters.

Treatment Processes: The number of drinking water treatment processes in the TDB is extensive and includes those most commonly employed and those less commonly employed but known to be effective. Information upon which the treatment process effectiveness depends is provided and includes key process and water quality parameters and the contaminant's importance.

Use highlights:

  • Identify effective drinking water treatment processes.
  • Plan for future treatment plant upgrades.
  • Assist regulators in best available technology and CCL decisions.
  • Provide information to first responders to spills or emergencies.
  • Recognize research needs.
  • Complement literature reviews and literature searches.

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Navigating the TDB

Find a Contaminant

The Find a Contaminant option contains several tabs of information on each contaminant. After selecting a contaminant, the overview page displays the following tabs:

  1. Overview: Provides a description of information on the selected contaminant. The CAS number, synonyms, contaminant type, and available images are displayed.
  2. Treatment Processes: Provides a short description of a contaminant and the treatment processes is provided. A description outlining useful information about the treatment processes as they relate to the contaminant may be provided.
  3. Properties: Provides a list of parameters that provide details about a contaminant in sortable columns.
  4. Fate and Transport: Provides a list of detailed fate and transport parameters on a contaminant in sortable columns.
  5. References: Lists reference information for the selected contaminant in sortable columns. This tab provides the most comprehensive group of reference information on a particular contaminant within the TDB.

Find a Treatment Process

The Find a Treatment Process tab allows a manual search for a particular treatment process. After selecting a process, the overview page displays the following tabs:

  1. Overview: Provides a description of the treatment process and any available images.
  2. Contaminants: Allows a search for particular contaminants tested against selected treatment process. Selecting a contaminant displays the contaminant/treatment process summary page.
  3. References: Lists reference information for the selected treatment process in sortable columns.

Contaminant and Treatment Process Summary

This page provides an overview of the effectiveness of a combination of the treatment process and contaminant selected. The page displays the following tabs:

  1. Overview: Provides an overview of information about the selected contaminant and treatment process combination. An overview of the effectiveness of the combination and any available images are provided.
  2. Data: Provides information for the selected contaminant and treatment process combination in sortable columns. Exporting information from the table into a spreadsheet file allows for further manipulation.
  3. References: Lists reference information for the selected contaminant/treatment process in sortable columns.

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Future Updates

Information in the TDB will be routinely reviewed to keep it current. As resources allow, the number of contaminants in the TDB will increase annually to include other regulated and unregulated drinking water contaminants. For a list of anticipated contaminants, see the TDB Future Contaminants page. We appreciate feedback for upgrades to the TDB, including contaminants you would like to see added.

Support and Feedback

For questions, comments, or suggestions, contact us at tdb@epa.gov.

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