Thurston County, Washington

Martin Luther King Jr. Day - Monday, January 19

County facilities will be closed on Monday, January 19 in observance of Martin Luther King Jr. Day.

The content on the Thurston County website is currently provided in English. We are providing the “Translation” for approximately 10 languages. The goal of the translation is to provide visitors with limited English proficiency to access information on the website in other languages. The translations do not translate all types of documents, and it may not give you an exact translation all the time. The translations are made through an automated process, which may not result in accurate or precise translations, particularly of technical and legal terminology.
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Thurston County Washington

Community Planning and Economic Development

Critical Areas Ordinance (CAO)

What's Next

Wednesday, January 21

Ask a Geologist

Join us before the Planning Commission meeting on January 21 at 5:30 in the Thurston County Atrium (3000 Pacific Ave SE). There will be a very brief presentation and plenty of time for your Thurston County geology questions! 

Planning Commission

Stay for the Planning Commission meeting starting at 6:30 to learn more about the Critical Areas Ordinance update.


Thurston County is updating the Critical Areas Ordinance!

Thurston County has started updating the Critical Areas Ordinance (CAO), with completion planned for the end of 2026. The CAO guides how land can be developed safely near environmentally sensitive areas. It draws on the best available science to balance property use with the protection of human health and safety, water quality, and wildlife habitat – for today and future generations. 

The CAO update is currently being reviewed by the Planning Commission while County staff works on collecting Best Available Science (BAS) and writing draft code. Nothing is finalized yet, and the County wants to hear your feedback and ideas. Through next year, there will be many opportunities for the community to share feedback and ask questions. You input will be essential in shaping this process.

Updates to the CAO could include:  

  • Using the best available science to protect critical areas.
  • Making it easier for landowners to engage in conservation work on their properties.
  • Clarifying the permitting process.

For questions about Thurston County's Critical Areas Ordinance Update, please contact Associate Planner Claire Swearingen at Claire.Swearingen@co.thurston.wa.us or call 360-968-9989. If you have questions about the current code, project specific concerns, or need help with permitting, please contact the Thurston County BDC.

Sign Up for Email Updates!

Submit Comments & Best Available Science!

 

The Five Critical Areas

Washington state law, Growth Management Act (GMA), requires cities and counties to protect five types of critical areas, including:

  • Geologically hazardous areas at risk for landslides, like cliffs or steep slopes.
  • Frequently flooded areas such as floodplains and high groundwater zones.
  • Critical aquifer recharge areas that help water soak back into the ground, so there's plenty for us to drink and fish to swim in.
  • Wetlands that help filter dirt and pollutants from the water as it soaks back into the ground.
  • Fish and wildlife habitat conservation areas like lakes, rivers, streams, prairies, and forests.

 

Resources: Best Available Science and Laws

The Thurston County CAO is detailed in Title 24 of the County Code of Ordinances.

Learn more from the Department of Commerce Critical Areas Handbook.

Learn about Best Available Science from our BAS Fact Sheet.

Planning Commission Meetings

Throughout the update development process, staff will bring presentations on State guidance, best available science, and policy decisions to the Planning Commission. The Planning Commission will also review code drafts. Community members are encouraged to provide public comment and feedback at any Planning Commission meeting. 

Meeting Date  

Topic  

 Documents and Presentations
9/17/2025 Introduction to the Critical Areas Ordinance update

Staff Report

Presentation

10/1/25  

Permitting/front counter demonstration  

 None

10/15/25  

Draft schedule overview and prioritization discussion  

Staff Report

Presentation

11/5/25  

Schedule finalization (as needed) 

 Meeting Cancelled

11/19/25  

Overview of state guidance and BAS  

Staff Report

Presentation

12/3/25  

Geologic Hazard Areas Concepts 

  

12/17/25  

Invite DNR to present new landslide mapping 

  

1/7/26  

Frequently Flooded Areas and Critical Aquifer Recharge Areas Concepts 

  

1/21/26  

No Meeting 

  

2/4/26  

Geo Hazards code presentation 

  

2/18/26  

FFA and CARA code presentation 

  

3/4/26  

Wetlands  

  

3/18/26  

Wetland and Hydrologic FWHCAs  

  

4/1/26  

Dryland Fish and Wildlife Habitat Conservation Areas  

  

4/15/26  

Presentation on SMP and HCP integration 

  

5/6/26  

No Meeting 

  

5/20/26  

Permit Processes, FWHCAs and Wetlands code presentation  

  

June-July 2026 

Final review, public hearing, and recommendation 

  

History

The first critical areas ordinance was adopted by Thurston's Board of County Commissioners in 1994, in response to the Washington Legislature enacting the Growth Management Act (GMA) in 1990. The last major update was adopted in 2012, with some minor updates since then. Since the last major update, State requirement and the best available science have changed.