Assurance Model

Alliance for Water Stewardship / Assurance Model

Introducing a mission-driven organisation

From October 2021, assurance services in relation to the AWS Standard will be contracted through Water Stewardship Assurance Services (WSAS), the mission-driven Conformity Assessment Body (CAB) for the AWS System.

WSAS shares our vision of a water-secure world and contributes to the AWS mission by providing credible assurance against the AWS Standard. WSAS provides initial certification, surveillance and re-certification services in line with requirements set by the AWS Technical Committee.

As the custodian of the International Water Stewardship Standard, AWS oversees WSAS performance to maintain the quality, integrity and credibility of the assurance scheme.

What does this mean for sites?

  • From 1 October 2021, new contracts for certification services must be established with WSAS
  • WSAS will be fully operational from 1 January 2022
  • Sites seeking to contract services for initial certification audits after 1 January 2022 should contact WSAS, via the email below
  • Sites seeking to be audited before 1 January 2022 should therefore engage with their existing CABs as normal
  • Sites whose certificates expire after 1 January 2022 should engage with WSAS for re-certification
  • For further guidance, please contact us.

Ensuring credibility

As a full code full member of the ISEAL Alliance, AWS’s assurance model meets the requirements of the ISEAL Assurance Code (ISEAL is the global membership organisation for credible sustainability standards). In addition, WSAS is working to achieve accreditation to ISO 17065, the globally recognised standard for certification bodies, at the earliest possible date.

Applications are now open to join the WSAS Certification Advisory Committee.


Website and audit platform

You can find out more about WSAS at

Through the WSAS website, you can access a new online reporting tool – the WSAS Audit Platform – built to enable consistent and efficient certification processes across all sites.

Frequently Asked Questions (FAQs)

For more information, please read our short FAQs section below.


What has changed in AWS assurance?

Under the new Assurance Model, the only thing that has changed is the delivery mechanism of AWS assurance. WSAS will fulfil the same functions as our previously accredited CABs, working in line with the requirements set by the Technical Committee.

AWS International will continue to conduct oversight and ensure the robustness of conformity assessment services. The key difference is that WSAS is now the sole CAB – a mission-driven subsidiary of AWS International, in pursuit of the same goals as AWS. This will align the goals of our assurance model with the rest of the AWS System.

In October 2020, the AWS Board reached the decision for AWS to move to delivery of assurance services through a mission-driven CAB, to provide a more streamlined approach that reduces complexities for users and further strengthens the credibility of AWS certification.

Why has AWS decided to change the Assurance Model?

Our aim is first and foremost to strengthen the credibility of AWS certification through closer oversight and consistent application of AWS requirements. More broadly, we aim to transform assurance into a genuine driver for growth. A key part of this is to minimise the complexities of the delivery model and focus on an improved user experience and, ultimately, more value for sites achieving certification.

How will I certify or recertify my site under the new assurance model?

Sites seeking certification should engage directly with WSAS to contract certification services from 1 October 2021. For more information, visit

What is the transition timeline?

1 October 2021: 

  • New contracts for certification services will be established between WSAS and sites seeking certification (initial or re-certification) to enable a smooth transition for audits to be conducted under WSAS from January 2022.
  • From 1 October 2021, our previously accredited CABs will not be able to secure new contracts for AWS certification.

1 January 2022:

  • WSAS is fully operational.
  • All initial AWS certification and re-certification services will be delivered through WSAS.

Who should I contact to get my site certified?

  • Sites seeking to contract services for initial certification audits after 1 January 2022 should arrange a contract with WSAS.
  • Sites whose certificate expires after 1 January 2022 should engage with WSAS for re-certification.

Will existing contracts be honoured?

Existing certification contracts that extend beyond January 2022 (covering a maximum of three years in line with the three-year AWS certification cycle) may still be honoured on condition that AWS and the relevant CAB finalise the necessary legal agreement to enable the CAB to continue to deliver contracted services. AWS has contacted all CABs explaining this process.

What about auditors?

Our network of highly trained auditors will ensure excellence in service delivery under the new assurance model. During this transition process, we will be taking steps to provide advanced training for auditors, aiming to maximise the quality and consistency of auditing against the AWS Standard.

Will the certification process change?

Just like in the current system, WSAS will follow the processes for audits and certification as established in the AWS Certification Requirements. A new IT platform, the WSAS Audit Platform will enable a consistent and efficient certification process across all sites. Sites seeking certification will be given access to the IT platform and guidance on its use.

How will integrity be maintained?

  • As a full code full member of the ISEAL Alliance, AWS’s assurance model meets the requirements of the ISEAL Assurance Code (ISEAL is the global membership organisation for credible sustainability standards). In addition, WSAS is working to achieve accreditation to ISO 17065, the globally recognised standard for certification bodies, at the earliest possible date.
    Adherence to these codes and standards will ensure that AWS and WSAS meets the recognised best practice for certification processes. Clear rules ensure that that neither AWS International (as the standard-setting body) nor the WSAS Board will participate in certification decisions.
    In addition, WSAS will include an independent Certification Advisory Committee tasked with providing advice and recommendations on:
    Certification processes implemented by WSAS, following regular assessments
    Ensuring the impartiality of WSAS certification processes
    Individual certification decisions for which the WSAS Director considers independent advice is needed

What will the cost of certification be?

As a mission-driven organisation, WSAS has a key role to play in ensuring AWS certification is accessible and keeping costs reasonable is a clear factor in this. At present, there is wide variability in the cost of AWS certification. WSAS will aim to achieve greater consistency and transparency in pricing and to ensure its pricing structure enables certification to be available to the widest spectrum of users.

Under WSAS, pricing will be aligned to our mission and the AWS strategic goals and the costs for clients will take into account both the complexities of the site and the level of certification it wishes to achieve. Quotations will be available from 1 October 2021.

How will WSAS be governed?

Governance arrangements for WSAS have been defined to meet two core objectives:

  • AWS Assurance is implemented to the highest standard and in full compliance with AWS System requirements, defined by the Technical Committee
  • AWS Assurance is fully aligned to the mission of AWS

To achieve this, WSAS will be governed by a Board of Directors. The WSAS Board will comprise five members. Three members will be independent. This enables WSAS to operate effectively as a legal entity while maintaining the oversight and mission focus needed as a subsidiary of AWS International.

The WSAS Board Chair will be independent with other independent positions representing specific functional expertise.

How does WSAS relate to the governance of the AWS System as a whole?

The AWS International Board is responsible for appointing all members of the WSAS Board to match skills and capabilities identified as a priority for the effective running of WSAS. Independent members are being recruited through an open application process, using criteria agreed by the AWS International Board.

WSAS will have a majority independent board that will receive a mandate from the AWS Board under which it will operate. This mandate will include both technical requirements (as defined by the Technical Committee) and ‘mission requirements’ – what it requires of WSAS to enable it to contribute to the AWS mission.

Crucially, the mandate will clearly stipulate that neither the AWS Board nor the Board of WSAS can be involved in certification decisions.

I have another question, who should I contact?

If you have any further questions, please don’t hesitate to get in touch, via the contact form below.


For more information and guidance, or to have a confidential discussion with our staff, please contact Water Stewardship Assurances (WSAS) using the form below.

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