*Updated for extension of comment period until July 26, 2024

Not all waterbodies in Washington meet the state’s definition of ‘clean’ – but that doesn’t always mean that those waters are polluted. Even in their most natural, unaltered states, some rivers, streams, lakes, and parts of Puget Sound may be warmer, have more sediment, or have a pH level that is different from what is usually considered normal for clean water. This is why Washington historically included provisions to address these natural conditions when setting water quality standards for the health of the state’s waters.

Having a standard to determine what is normal and natural for a particular waterbody is important information for setting discharge limits or knowing when action is needed to protect or restore water quality. However, Washington is currently without some of these provisions after a decision by the U.S. Environmental Protection Agency in 2021. Using guidance from EPA, the Washington Department of Ecology is now working to reestablish these natural conditions, and is seeking public input on its proposal.

The importance of natural conditions in clean water regulations

Nearly every state and many Tribal nations have a provision in their EPA-approved water quality standards to protect aquatic life based on the natural conditions of the water bodies. These provisions recognize that some rivers, streams, and estuaries naturally do not meet the general clean water criteria. For example, a naturally low-flowing stream in a prairie without any human alteration may have seasonally higher temperatures than the state’s temperature criteria set to protect fish.

Without these provisions, it would be difficult for Ecology to account for waters that naturally do not meet the state’s definition of clean. This matters because Ecology and all organizations working on clean water efforts need to focus the state’s pollution reduction efforts on waterbodies where humans are causing pollution, not on waterbodies that are naturally different.

Proposal to re-establish natural conditions

Ecology’s proposal includes draft rule language, a document that provides the technical background on natural conditions, methods to calculate natural protective criteria, a plan on how to implement the rule, and an evaluation of the potential costs and benefits.

Ecology is proposing to establish two options for recognizing natural conditions:

• A performance-based approach to determine natural conditions criteria for dissolved oxygen, temperature, and freshwater pH. This approach establishes a repeatable scientific method, like a recipe, to calculate natural protective criteria.
• A site-specific criteria approach for all pollutants that impact aquatic life. This approach would require rulemaking for an individual site (waterbody or watershed) where the natural conditions provisions are needed.

Ecology is also proposing to establish new limits on how much humans can change the temperature and dissolved oxygen of waterbodies that naturally do not meet state limits. EPA disapproved the state’s previous limits on temperature and dissolved oxygen when the federal agency took actions on the state’s natural conditions.

Once finalized and approved by EPA, the natural conditions provisions will be incorporated into Ecology’s clean water work, including permitting and water clean up plans.

Provide input

Ecology is accepting public comments on this rule through July 26, 2024.

Submit comments online, by mail, or at a public hearing:

• Comment online
• Mail to:
  Marla Koberstein
  Department of Ecology
  P.O. Box 47696
  Olympia, WA 98504-7696

Public hearings

Ecology is holding two virtual public hearings. Each event will provide an overview of the proposed rule and hold a question-and-answer period, followed by public comment.

• June 27, 2024, 1:30 p.m.
  Register for the webinar
  Join via phone: 1-253-205-0468  Meeting ID: 837 0878 5880
• July 2, 2024, 5:30 p.m.
  Register for the webinar
  Join via phone: 1-253-205-0468  Meeting ID: 874 9484 4813