Chapter 173-201A WAC (Natural Conditions)
Ecology adopted amendments to Chapter 173-201A WAC, Water Quality Standards for Surface Waters of the State of Washington.
We adopted amendments to the parts of the surface water quality standards that address natural conditions. We have natural conditions provisions because conditions in some water bodies naturally do not meet water quality criteria. For example, a naturally low-flowing stream in a natural prairie without any human alteration may have seasonally higher temperatures than the limit set to protect fish.
We added a new section and definition in rule to describe and reference a new method called a “performance-based approach” to determine natural conditions criteria values. Next year, we'll provide another opportunity to comment on a revised draft of the performance-based approach document that is referenced in the adopted rule. We plan to finalize this document in 2025.
In addition, we adopted the following changes:
- Updated minimal allowances for local and regional human impacts to fresh and marine waters for dissolved oxygen and temperature when the natural conditions represent the water quality criteria. We also added a definition for "local and regional sources of human-caused pollution."
- Updated the natural conditions criteria language to limit use to aquatic life criteria and described methods for determining natural conditions criteria values.
- Updated how site-specific analyses must be conducted and other minor changes to the site-specific criteria section to reflect the latest guidance.
Rulemaking timeline
Announcement phase (CR-101)
Filing date:
Sept. 27, 2022
Announcement documents
Rule development phase
Sept. 27, 2022 - early 2024Public input & involvement
April 23, 2024 – Preliminary Rule Webinar
During this workshop, we presented draft rule language and share our plan to include a method to calculate natural conditions criteria. We then opened it up for questions and informal feedback. We welcome feedback on our preliminary changes as we prepare a draft rule proposal for public comment later this spring.
View presentation slides (pdf)
March 1 and 2, 2023 – Public Informational Webinars
We hosted an informational webinar for the rulemaking to update our natural conditions provisions in the surface water quality standards, chapter 173-201A WAC. During this webinar, we provided an overview of:
- Natural conditions provisions – what they are and what they protect
- Importance of natural conditions in Washington
- Options and scope of the rulemaking
- Timelines and opportunities for public participation
View presentation slides (pdf)
Workshops offered via webinar allow individuals to view the presentation and ask questions via computer or mobile device.
Rule proposal phase (CR-102)
May 10, 2024
- Proposal Notice - CR-102 form
- Proposed rule language
- Draft Performance-Based Approach Rule Document
- Draft Technical Support Document
- Draft Rule Implementation Plan
- Preliminary Regulatory Analyses
- SEPA Checklist and Determination of Non-significance
- Focus Sheet
Comment period
Comments accepted from 12 a.m. on May 10, 2024, until 11:59 p.m. on July 26, 2024 (extended)
See above for documents related to the Proposal Phase of the rulemaking.
Public hearings
We held two public hearings on this rulemakings. The hearings began with a short presentation and question and answer session, followed by the opportunity to provide testimony. The hearings concluded once everyone who wanted to provide testimony had the opportunity to do so. Written comments received the same consideration as oral testimony.
- Thursday, June 27, 2024, 1:30 p.m.
- Tuesday, July 2, 2024, 5:30 p.m.
Webinars are an online meeting forum that you can attend from any computer using internet access.
Any information (e.g., personal or contact) you provide may be publicly disclosed and posted on the Internet.
To request ADA accommodations, contact Ecology’s ADA Coordinator by April 1, 2024, at:
- Phone: 360-407-6831 (voice)
- TTY: 877-833-6341 or 711 relay service
- Email:ecyadacoordinator@ecy.wa.gov
Rule adoption phase (CR-103)
Nov. 14, 2024
Dec. 15, 2024
Continuance filing (CR-102)
Filing Date:
July 11, 2024
Continuance documents:
- Continuance of proposal notice – CR-102 form
- Public comment period EXTENDED
- SEPA Determination of Nonsignificance (DNS) and Environmental Checklist (extended public comment period)
Comment period
Comments are due by 11:59 p.m. on July 26, 2024 (originally July 12, 2024)
Related links
Contact information
Marla Koberstein
Rulemaking Lead
marla.koberstein@ecy.wa.gov
360-628-6376
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Accessibility
To request ADA accommodation for disabilities, or printed materials in a format for the visually impaired, contact Ecology's ADA Coordinator by email at ecyadacoordinator@ecy.wa.gov, or call 360-407-6831. People with impaired hearing may call Washington Relay Service at 711. People with speech disability may call TTY at 877-833-6341.