Updates to the surface water quality standards

We update the surface water quality standards to incorporate the latest science and to meet Ecology's priorities and commitments regarding the standards.

The two process to review and revise the standards are a triennial review and our rulemaking process.  

Surface water quality standards

On Aug. 1, 2016, we adopted revisions to Water Quality Standards for Surface Waters of the State of Washington, Chapter 173-201A WAC and sent it to the federal U.S. Environmental Protection Agency (EPA) for review.

The EPA reviewed our adopted standards, and on Nov. 15, 2016, announced action to approve in-part — and disapprove in-part — our rule.

Concurrent with the action on our rule, the EPA promulgated federal human health criteria applicable to Washington waters.

Reviewing and revising the surface water quality standards

The triennial review

Federal regulations require us to hold public hearings to review applicable surface water quality standards and, as appropriate, adopt new or modified standards. This process is called a triennial review.

The triennial review provides an opportunity to discuss the priorities and commitments we make with the EPA — and others — regarding the surface water quality standards.

Overview of the triennial review process

We conduct a triennial review about every three years. The triennial review is not part of a rulemaking process, but instead is used to:

  • Provide a forum to discuss issues of interest regarding the water quality standards and their implementation.
  • Discuss what new initiatives are being developed by the EPA.
  • Solicit suggestions for where guidance is needed to implement the current standards.
  • Solicit suggestions for what new or revised criteria are needed in the regulation.
  • Discuss the progress with ongoing standards-related efforts.
  • Formally modify the long-term strategy and timeline for developing guidance and revising the surface water quality standards.

2010 triennial review

The latest triennial review for our surface water quality standards was held from Nov. 1, 2010 through Dec. 17, 2010.

We reviewed all comments received during the comment period and developed a five-year plan of prioritized topics. We also created a responsiveness summary based on comments received, including our response to each comment.


Rulemaking topics are selected based on the goal of getting the greatest environmental and/or administrative benefit.

Topics are prioritized based on:

  • The expected environmental benefits.
  • Technical complexity.
  • Available staff resources.
  • Federal mandates.
  • Need for change in the water quality standards rule.
We will maintain a long-term list of prioritized topics. Along with list we make commitments to implement changes — in rulemaking or otherwise.
  • The short-term priorities identified will be focused on for one-to-five years based on our ability to anticipate and commit staff resources. These priorities will be built into the our our commitments to the EPA in our Performance Partnership Agreement.
  • The long-term priorities will be reviewed — and modified where appropriate — during each triennial review.

Why do we use this approach?

This approach allows us to base rulemaking topics on the relative environmental value of each topic, and our ability to complete the project.

For example, we may find that we can complete four moderate-value projects in the same time as one large-value project, and thus have greater overall benefits. This approach also allows us to consider the costs and benefits of an action and select the least costly course of action.

We focus primarily on short-term formal commitments to avoid over-committing and to keep the process flexible enough to respond to any new priorities developed through the triennial review process.