Skip to main content
NSF Home

Ontario Drinking Water Quality Management Standard (DWQMS) Verification

Protecting Ontario’s municipal drinking water through trusted, independent verification.

Ontario’s Safe Drinking Water Act, 2002 requires that all municipal residential drinking water systems be overseen by an accredited operating authority with a documented Quality Management System that meets the Drinking Water Quality Management Standard (DWQMS). NSF International Strategic Registrations (NSF-ISR) is an approved accreditation body authorized to provide third‑party verification under this framework. 

Our DWQMS verification services help municipal water authorities demonstrate compliance, strengthen public confidence, and continuously improve system performance.

What does DWQMS accreditation mean?

DWQMS verification is an independent assessment confirming that an operating authority’s Quality Management System meets Ontario’s regulatory requirements for municipal drinking water. The standard includes elements such as system risk assessment, documented processes, operational controls, and continual improvement.

It demonstrates that your organization:

  • Follows a structured and documented approach for ensuring safe drinking water.
  • Meets the mandated elements of the DWQMS.
  • Maintains oversight, accountability, and continual improvement as required by the province.

How DWQMS accreditation works

NSF conducts verification through a structured process aligned with provincial requirements:

  • 1

    Document review

    Assessment of your Quality Management System documentation, including policies, risk assessments, and operational procedures aligned to DWQMS elements.

  • 2

    On‑site evaluation

    Auditors evaluate implementation across the drinking water system, verifying practices, roles, training competencies, and monitoring activities.

  • 3

    Reporting and corrective actions

    You receive detailed findings identifying strengths and any required corrective actions.

  • 4

    Verification decision

    Upon successful completion, NSF‑ISR issues an accredited certificate demonstrating compliance with DWQMS.

  • 5

    Ongoing surveillance

    Annual surveillance helps ensure continuous conformity and improvement, reflecting updated DWQMS requirements such as risk assessment processes, organizational structure documentation, and personnel competency elements.

Who needs DWQMS accreditation?

Under the Safe Drinking Water Act, accreditation is mandatory for operating authorities responsible for municipal residential drinking water systems in Ontario.
DWQMS verification is essential for:

  • Municipalities.
  • Operating authorities managing treatment, distribution, or both.
  • Public infrastructure agencies responsible for drinking water safety.

The standard also applies to distribution‑only systems and is aligned with Ontario’s Municipal Drinking Water Licensing Program.

What you gain with NSF

  • Specialized DWQMS expertise: Our team includes auditors with more than 10 years of quality management experience and deep knowledge of water system operations.
  • Efficient, practical verification: Auditors draw on industry familiarity to streamline the verification process while maintaining rigorous compliance expectations.
  • Support for certificate transfers: Our experts can help municipal authorities manage the transition of existing certifications.
  • Proven credibility: NSF‑ISR is authorized by the province as an approved accreditation body for DWQMS.

Access the list of NSF issued certificates

View the public directory of DWQMS accredited certificates for operating authorities verified by NSF ISR.

Why trust NSF in drinking water quality verification?

  • 1

    NSF leads global standards for water products and safety

    NSF is recognized as a global leader in establishing and maintaining standards for water product quality and safety. It convenes experts, regulators, manufacturers, and users to develop consensus‑based standards that govern the entire water sector.

    This leadership gives NSF deep technical visibility across the drinking water industry, from treatment products to system components to water system performance.

  • 2

    Longstanding history in public health and water safety

    NSF has been a trusted authority in public health since 1944, building a reputation for developing standards that protect human health. 

    This legacy of scientific integrity, spanning 80 years, reinforces NSF’s role as a dependable verifier of drinking water quality and compliance.

  • 3

    Accredited expertise across water systems, chemicals, and treatment technologies

    NSF certifies and verifies an exceptionally broad range of water‑related systems, including municipal water systems, treatment chemicals, filtration equipment, and materials used in distribution networks. 

    Because NSF works “source to tap to sewer,” it possesses unmatched technical understanding of the entire lifecycle of drinking water systems.

  • 4

    Global recognition and ANSI accreditation

    NSF is accredited by ANSI as a standards development and certification body, meaning its protocols meet the highest levels of international oversight and governance.

    This accreditation signals that NSF’s processes are impartial, technically sound, and globally aligned.

Resources

Ready to begin?

Our team is here to support your certification journey, from initial readiness through ongoing compliance.
Contact us to discuss DWQMS verification or certificate transfer options.