Waivers for Public Water System Contaminant Monitoring

Public Water System Water Quality Monitoring

Water quality monitoring of public water systems is a critical element of compliance activities under the federal Safe Drinking Water Act (SDWA), as incorporated by reference into Minnesota Rules.

The SDWA requires public water systems to sample water regularly and analyze for a broad range of potential contaminants. If unacceptable levels of contaminants are found, the water supply owner is legally responsible for informing the people who use the water and for taking steps to eliminate potential health hazards.

Under the SDWA, individual public water systems are responsible for taking water samples, submitting them to an accredited laboratory for analysis and reporting the results to the state. To provide for comprehensive surveillance, lessen the burden on water supply operators, promote compliance, and help ensure consistent approaches, most of the SDWA required samples in Minnesota are collected by field staff from the Minnesota Department of Health (MDH). As a result, Minnesota’s public water systems have one of the best records in the nation for compliance with SDWA monitoring requirements.

SDWA monitoring waivers in Minnesota

The SDWA allows for monitoring of certain contaminants to be reduced, or suspended entirely, if there is firm evidence that a water source is not vulnerable to a particular contaminant. Waivers are only granted for chronic contaminants – those that produce health effects only after long term exposure. Waivers are not available for acute contaminants – such as microbial pathogens or nitrate – which can create health impacts from short term exposure.

Specifically, under the SDWA, MDH may issue waivers to community and nontransient noncommunity systems determined to be not vulnerable to certain inorganic compounds (IOCs), volatile organic compounds (VOCs), and synthetic organic compounds (SOCs). Waivers are granted to the system at the sampling point level (e.g., for a particular well or intake). In determining whether a waiver is appropriate, MDH reviews the current and historic usage/presence of the contaminant, the construction of the well (for groundwater sources), previous monitoring results, and other indicators of potential vulnerability.

In Minnesota, MDH makes a determination of waiver status and adjusts the system’s monitoring schedule accordingly. In other states, the public water system may need to apply for waiver(s). A benefit of MDH making statewide determinations of waivers is that it provides equitability (in that all systems are considered for waivers) and a consistent, systematic approach. Employing waivers allows MDH and public water systems to focus resources on contaminants that are most likely to be issues and avoids expending resources in instances where sources are not vulnerable to contamination.

For more information

For more information about SDWA waivers, and to learn whether your public water system has any waivers, contact MDH’s Drinking Water Protection Section at: health.drinkingwater@state.mn.us or 651-201-4700.