# WAC 173-201A-310: WAC 173-201A-310. Tier I—Protection and maintenance of existing and designated uses

> Washington · Regulations · In force

URL: https://www.frixlaw.com/law-library/statutes/STATE_WA_ADC_173_201A_310

## Section

- **Citation:** WAC 173-201A-310
- **Heading:** WAC 173-201A-310. Tier I—Protection and maintenance of existing and designated uses
- **Jurisdiction:** Washington
- **Kind:** Regulations
- **Status:** In force
- **Text as of:** August 14, 2026
- **Source:** Compiled text
- **Location:** Washington Administrative Code / Title 173 / Chapter 173-201A / Section 173-201A-310

## Text

(1) Existing and designated uses must be maintained and protected. No degradation may be allowed that would interfere with, or become injurious to, existing or designated uses, except as provided for in this chapter.
(2) For waters that do not meet assigned criteria, or protect existing or designated uses, the department will take appropriate and definitive steps to bring the water quality back into compliance with the water quality standards.
(3) Whenever the natural conditions of a water body are of a lower quality than the assigned criteria, the natural conditions constitute the water quality criteria. Where water quality criteria are not met because of natural conditions, human actions are not allowed to further lower the water quality, except where explicitly allowed in this chapter.

## Nearby sections

- [WAC 173-201A-010 WAC 173-201A-010. Purpose](https://www.frixlaw.com/law-library/statutes/STATE_WA_ADC_173_201A_010.md)
- [WAC 173-201A-020 WAC 173-201A-020. Definitions](https://www.frixlaw.com/law-library/statutes/STATE_WA_ADC_173_201A_020.md)
- [WAC 173-201A-200 WAC 173-201A-200. Fresh water designated uses and criteria](https://www.frixlaw.com/law-library/statutes/STATE_WA_ADC_173_201A_200.md)
- [WAC 173-201A-210 WAC 173-201A-210. Marine water designated uses and criteria](https://www.frixlaw.com/law-library/statutes/STATE_WA_ADC_173_201A_210.md)
- [WAC 173-201A-230 WAC 173-201A-230. Establishing lake nutrient criteria](https://www.frixlaw.com/law-library/statutes/STATE_WA_ADC_173_201A_230.md)
- [WAC 173-201A-240 WAC 173-201A-240. Toxic substances](https://www.frixlaw.com/law-library/statutes/STATE_WA_ADC_173_201A_240.md)
- [WAC 173-201A-250 WAC 173-201A-250. Radioactive substances](https://www.frixlaw.com/law-library/statutes/STATE_WA_ADC_173_201A_250.md)
- [WAC 173-201A-260 WAC 173-201A-260. Natural conditions and other water quality criteria and applications](https://www.frixlaw.com/law-library/statutes/STATE_WA_ADC_173_201A_260.md)
- [WAC 173-201A-300 WAC 173-201A-300. Description](https://www.frixlaw.com/law-library/statutes/STATE_WA_ADC_173_201A_300.md)
- [WAC 173-201A-310 WAC 173-201A-310. Tier I—Protection and maintenance of existing and designated uses](https://www.frixlaw.com/law-library/statutes/STATE_WA_ADC_173_201A_310.md)
- [WAC 173-201A-320 WAC 173-201A-320. Tier II — Protection of waters of higher quality than the standards](https://www.frixlaw.com/law-library/statutes/STATE_WA_ADC_173_201A_320.md)
- [WAC 173-201A-330 WAC 173-201A-330. Tier III—Protection of outstanding resource waters](https://www.frixlaw.com/law-library/statutes/STATE_WA_ADC_173_201A_330.md)
- [WAC 173-201A-332 WAC 173-201A-332. Table 332 — Outstanding resource water designations by water resource inventory area (WRIA)](https://www.frixlaw.com/law-library/statutes/STATE_WA_ADC_173_201A_332.md)
- [WAC 173-201A-400 WAC 173-201A-400. Mixing zones](https://www.frixlaw.com/law-library/statutes/STATE_WA_ADC_173_201A_400.md)

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Source: Frix Law Library, https://www.frixlaw.com/law-library/statutes/STATE_WA_ADC_173_201A_310. Check the current official text before relying on it. Not legal advice.