A water quality standards (WQS) variance is a tool that states, territories and authorized tribes may use to improve water quality over time.  These time-limited WQS strike a balance between providing states, territories, authorized tribes and dischargers the time and flexibility to make incremental water quality improvements reflecting the best that can be achieved in a given time period, with accountability measures to assure the public that progress will occur.  A WQS variance can be used when it is uncertain how much progress can be achieved, but it is known that some progress is possible, and states, territories and authorized tribes don’t want to give up on working toward water quality improvement.

In August 2015, EPA published a final rule in the Federal Register updating the federal water quality standards regulation to improve implementation of the Clean Water Act (80 FR 51019) in six key areas. Specifically,  EPA established the WQS variance requirements at 40 CFR 131.14 to provide a better-defined pathway for states, territories and authorized tribes to adopt WQS variances to improve water quality, and to increase transparency and enhance opportunities for meaningful public engagement at the state, territorial, tribal and local levels.

WQS Variance Resources

This WQS Variance Overview presentation explains the basics of WQS variances and how a WQS variance can help to make water quality improvements.

• WQS Variance Overview Presentation (PDF) (40 pp, 930 K)

Disclaimer: This online presentation and any associated links have been prepared by EPA staff for informational purposes only. As such, this presentation and any associated links are not binding on EPA or the public and have no legal effect. They do not constitute an EPA statute, regulation or other requirement and do not substitute for such authorities. In addition, the presentation and any associated links have not been reviewed or endorsed by EPA management. Thus, they are not intended or written as official statements of EPA's scientific views, policies, guidance, or requirements and cannot be used or cited as evidence of EPA's position on any matter.

This online tool is designed to help states, territories and authorized tribes determine whether a WQS variance is appropriate for a particular situation and, if so, how to navigate the requirements of 40 CFR 131.14.

• Water Quality Standards Variance Building Tool

EPA has also developed several resources to accompany the WQS Variance Building Tool including a collection of frequently asked questions that will help highlight what information the state, territory, or authorized tribe should be thinking about before they begin using this tool, and a checklist for determining if a state has met the regulatory requirements for a WQS variance applicable to specific dischargers.

• Water Quality Standards Variance Building Tool – FAQs (PDF) (2 pp, 140 K, July 2017, EPA 820-F-17-016)
• Checklist For Evaluating State Submission Of Discharger-Specific Water Quality Standards Variances (PDF) (2 pp, 270 K)