Water supplies meeting treatment requirements

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What we track

Blue Accounting is tracking the percentage of water supplies meeting treatment requirements across the Great Lakes Basin.

Water treatment around the Great Lakes basin

Prior to distribution to water customers, sources of drinking water are treated to ensure that high-quality water is delivered from treatment plants (which may be owned by local governmental authorities or private business enterprises). Blue Accounting’s Drinking Water issue is focused on water supplies serving the public, defined as community water supplies in the United States and municipal water supplies in Canada. These water supplies treat water extracted from a source, whether that source in a Great Lake, inland waterbody, or groundwater.

Companion assessments conducted under the Great Lakes Water Quality Agreement more narrowly examine the population served by community water systems that meeting all health-based standards for the U.S. and treated water sample results in compliance with water quality standards for Ontario.

Blue Accounting is also examining health-based standard violations, while adding acute health-based, monitoring and reporting, and public notification categories of violations, providing a more-detailed picture of treated water quality and related requirements that assure state and provincial agencies, the federal government, and ultimately drinking water customers are informed of new or emerging issues with water treatment at the nearly ***** water supplies in the Great Lakes basin.

Why it matters

Trust in water — and the systems that provide water — starts at the tap. Treatment requirements are carefully established by federal, state, and provincial governments to protect public health.

State of the Great Lakes 2019 report, accessible at: https://binational.net/2020/06/03/sogl-edgl-2019-2/ with additional input provided by members of the Drinking Water issue work group's Water Treatment Sub-team.

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What do the violation categories include?

  • Health-Based Violations: Violations of maximum contaminant levels (MCLs) or maximum residual disinfectant levels (MRDLs), which specify the highest concentrations of contaminants or disinfectants, respectively, allowed in drinking water; or of treatment technique (TT) rules, which specify required processes intended to reduce the amounts of contaminants in drinking water.
  • Acute Health-Based Violations: Health-based violations that have the potential to produce immediate illness.
  • Monitoring and Reporting (MR) Violations: Failure to conduct regular monitoring of drinking water quality, as required by SDWA, or to submit monitoring results in a timely fashion to the state environmental agency or EPA.
  • Public Notice (PN) Violations: Violations of the SDWA public notification requirements to immediately alert consumers if there is a serious problem with their drinking water that may pose a risk to public health.
  • Other Violations: Violations of other requirements of SDWA, such as issuing annual consumer confidence reports, or conducting periodic sanitary surveys.

EPA ECHO Drinking Water Dashboard