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Thurston County, Washington

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.

Community Planning and Economic Development

Thurston County is home to several federally endangered species. If you want to build on land that is mapped with their habitat, apply for a county permit using the county's HCP rules and paperwork. For most applicants, the county's HCP process covers both the federal and local requirements. 

Learn more

You can go straight to the Permitting Applications page for the HCP forms and examples as noted above, or you can do some of your own research first.

Start by checking the HCP section of the Permitting Map before you apply, and use the mitigation estimate form to estimate the mitigation fee. No more waiting for June-October gopher inspections to see if you need a federal permit. Permit decisions will be fully in county hands, and can be made year-round. 

  1. Projects Must Be Designed Using Best Management Practices 
    Design your project using the HCP Best Management Practices outlined in the HCP (starts on page 1 of Appendix C, which is page 230 of the PDF document) because the County’s federal permit from U.S. Fish & Wildlife Service requires it. If HCP BMPs are not used to the fullest extent possible, the County will likely ask for revisions to your site plan.
  2. Mitigation Fee is Based on Size of Impact
    Mitigation fees are based on how much HCP habitat your project impacts. Impact a lot, pay a larger fee. Impact a little, pay a smaller fee. Your plans affect your mitigation fee. 


  • Projects on properties with mapped HCP soils go through the HCP permit process. 
  • The County will visit the project property to make sure County maps match real-world conditions, but visits will happen year-round. 
  • The County will check site plans for use of HCP Best Management Practices. If not used to the fullest extent, revisions will likely be requested because the County's federal permit requires this.
  • HCP mitigation fees will be calculated by County staff based on final submitted site plan and project materials, when and if the HCP goes into effect. 
  • Permitted projects will get a Certification of Inclusion to show coverage by the County’s HCP & Federal Permit. 
  • Other County permit application processes and regulations apply.


Image showing 4 actions that make up conservation fitted together as puzzle pieces.

The County's HCP takes a landscape approach to conservation in an effort to ensure the survival of the covered species. The HCP will coordinate a large-scale reserve system to replace the current piecemeal mitigation process. This Conservation Land System will create mitigation credits to offset permitted development impacts. 

Acres of Protection

This system may preserve and restore up to 3,500 acres to provide for the conservation of the Mazama pocket gopher, Oregon spotted frog, Oregon vesper sparrow, and Taylors checkerspot butterfly, animals covered by the County's HCP.  The plan is to acquire and include large tracts of contiguous conserved properties, including working agricultural lands. Priority will be given to land already occupied by the covered species.

Landscape Approach, Ecologically Valuable

The HCP-covered species share a similar prairie habitat, as well as provide habitat for other at-risk species.  The conservation of these lands and management practices will not only account for multiple HCP-covered species, but also provide managed habitat for species that too rely on prairie habitat. The reserve system and associated conservation measures will bring more ecological benefits to these HCP and other species with similar habitat needs, as well as complementing the species recovery efforts of federal and state wildlife agencies. 

Managed to Biologically-Sound, Measurable Standards

Prior to release as mitigation credits, all HCP conservation land types will meet performance standards in the HCP (See HCP pps 118 & 120, tables 7.1 and 7.2), and will include:

  • Baseline report.
  • Site management plans.
  • Legal permanent protection.
  • Long term stewardship fund (endowment).

    Table listing the types of conservation land and their definitions








Conservation Land System Map

map of proposed HCP land conservation areas


Habitat Conservation Plan 

Fact Sheets 



Regulatory Documents


Environmental Impact Statement 

HCP Economic Analysis 

Public Participation 


Supporting Science

Documents Related to HCP Planning & the Federal ITP Permit (PDFs)


Endangered Species Act Listings & Petition (PDFs)


Species & Habitat Science (PDFs)


Bird (Oregon Vesper Sparrow & Streaked Horned Lark) 


Butterfly (Taylor's checkerspot) 


Frog (Oregon spotted)


Gopher (Mazama Pocket Gopher subspecies)


Important Notice: The reports, memos and documents on this page do not constitute the full body of knowledge and supporting science used to develop the Thurston County Habitat Conservation Plan (HCP), the Environmental Impact Statement for the HCP, or related documents. A detailed list can be found by reviewing the references cited in the documents on this page.

Action: An activity or program of any kind authorized, funded, or carried out, in whole or in part, by a federal agency in the United States.

Action area: All areas to be affected directly or indirectly by the federal action and not merely the immediate area involved.

Adaptive management: A cyclical process whereby managers treat actions as experiments from which they improve management actions.

Buffer: Distance outside the footprint that defines the area indirectly impacted by an activity.

Candidate species: Candidate species are plants and animals for which the U.S. Fish and Wildlife Service has sufficient information on their biological status and threats to propose them as endangered or threatened under the Endangered Species Act, but for which development of a proposed listing regulation is precluded by other higher priority listing activities.

Community: A group of interacting plants and animals inhabiting a particular area.

Compliance monitoring: An evaluation of whether the process did what it said it would accomplish.

Conservation: As defined by Section 3 of the ESA, to use and the use of all methods and procedures necessary to bring any endangered or threatened species to the point at which the measures provided are no longer necessary. Such methods and procedures include, but are not limited to, all activities associated with scientific resource management such as research, census, law enforcement, habitat acquisition and maintenance, propagation, live trapping, and transplantation, and in the extraordinary case where population pressures within a given ecosystem cannot be otherwise relieved, regulated taking.

Conservation action/measure: A specific conservation tool employed in a specific location. May include, but is not limited to, habitat acquisition and habitat restoration.

Consultation: The process required of a federal agency under Section 7 of the ESA when any activity authorized, carried out, or conducted by that agency may affect a listed species or designated critical habitat. Consultation is with the U.S. Fish and Wildlife Service (or National Marine Fisheries Service) and may be formal or informal.

Covered Activity: These are activities that are included in the HCP and covered for incidental take by the incidental take permit.

Covered Species: These are species that are included in the HCP and covered for incidental take by the incidental take permit.

Credits: Quantified, verified, and tradable units of environmental benefit from conservation or restoration action.

Critical Areas Ordinance: Is a set of regulations that govern how land is developed in environmentally sensitive areas and in areas where development would pose a threat to humans or wildlife. Critical areas include important fish and wildlife habitat areas (prairies, rivers, streams); wetlands; aquifer recharge areas; frequently flooded areas; and geologically hazardous areas. The state Growth Management Act (Chapter 36.70A RCW) requires protection of these areas.

Critical habitat: Specific areas within the geographic area occupied by the species on which are found those physical and biological features essential to the conservation of the species and which may require special management considerations or protection.

Debits: Quantified, verified, and tradable units of environmental impact, calculated as the difference between the functional scores of the pre-project and anticipated post-project conditions.

Delist: To remove a plant or animal species from the list of endangered or threatened species.

Ecology: The study of the inter-relationship among organisms and between organisms and between all aspects, living and nonliving, of their environment.

Ecoregion: A relatively large land and water area containing geographically distinct assemblages of natural communities, with approximate boundaries. These communities share a large majority of their species, dynamics, and environmental conditions, and function together effectively as a conservation unit at the continental and global scales.

Ecosystem: A discrete unit that consists of living and nonliving parts, interacting to form a stable system.

Effectiveness Monitoring: Monitoring to determine whether the restoration or enhancement techniques are meeting the management objective.

Endangered species: Those species threatened with extinction throughout all, or a significant portion, of their range. Species can be listed as endangered or threatened for a number of reasons, including disease or predation. Natural or human factors affecting chances for survival: over utilization for commercial, scientific, or recreational purposes, or current or threatened destruction of habitat or range.

Federal Register: The official daily publication for actions taken by the Federal government, such as rules, proposed rules, and Notices of Federal agencies and/organizations, as well as Executive Orders and other Presidential documents.

Fully Forested: One-hundred percent tree canopy cover, with shrub and fern understory. Must be confirmed by staff.

Graminoids: Grasses, sedges, and rushes.

Habitat: The living place of a species or community characterized by its physical or biotic properties.

Habitat Conservation Plan (HCP): HCPs are planning documents required as part of an application for an incidental take permit. They describe the anticipated effects of the proposed taking; how those impacts will be minimized, or mitigated; and how the HCP is to be funded. HCPs can apply to both listed and nonlisted species, including those that are candidates or have been proposed for listing.

Harass: To intentionally or negligently, through act or omission, create the likelihood of injury to wildlife by annoying it to such an extent as to significantly disrupt normal behavior patterns such as breeding, feeding, and sheltering.

Harm: To perform an act that kills or injures wildlife; may include significant modification of habitat or degradation when it kills or injures wildlife by significantly impairing essential behavioral patterns including breeding, feeding, or sheltering.

Historic range: The geographic area where a species was known to or believed to occur within historic time.

Host plant: A particular plant species required of butterflies during egg laying and for food during the larvae and pupae life stage.

Impacts: Impacts may be negative or positive. Negative impacts are ecological stresses to a species and the source of that stress. Positive impacts are impacts whose net effect is beneficial to the species, and may include such activities as mowing or burning.

Incidental take: Take that results from, but is not the purpose of, carrying out an otherwise lawful activity.

Incidental take permit: A Permit issued under section 10(a)(1)(B) of the ESA to a non-federal party undertaking an otherwise lawful project that might result in the take of a threatened or endangered species. An application for an incidental take Permit is subject to certain requirements, including preparation of habitat conservation plan.

Indirect effect: An effect caused by a proposed action taking place later in time than the action, but is still reasonably certain to occur (Section 7 of ESA).

Listed species: A species, subspecies, or distinct population segment that has been added to the federal list of endangered and threatened wildlife and plants.

Mitigation: The offset of an environmental impact with a compensatory environmental benefit, typically generated through ecological protection, restoration, or enhancement and verified through a crediting program.

Monitoring: Repeated measurements carried out in a consistent manner so that observations are comparable over time.

Native species: Those species present in part or all of a specified range without direct or indirect human intervention, growing within their native range and natural dispersal potential.

Nectar Plant: A particular plant species required of adult butterflies for food/energy. Non-native species: Those species present in a specified region only as a direct or indirect result of human activity.

Participation Agreement: This is a document issued by Thurston County that enrolls a landowner into the HCP for purposes of obtaining coverage under the county’s incidental take permit.

Persons: Includes individuals, corporations, partnerships, limited liability corporations, limited liability partnerships.

Petition: A formal request from an interested individual or organization to list, reclassify, or delist a species, or to revise critical habitat for a listed species.

Prairie Habitat Assessment Methodology: A tool to help standardize a method for mitigating impacts to prairie ecosystems through Thurston County’s Critical Areas Ordinance.

Population: A group of individuals of a species living in certain areas maintaining some degree of reproductive isolation.

Potential Occupancy: A parameter that ranges from zero to one that models the likelihood for occupation of a habitat type by a target prairie-associated species.

Range: The geographic area a species is known to or believed to occupy.

Recovery: A reduction of the risk of extinction to the point that, based upon best available science, it is reasonably sure that the species will remain secure into the foreseeable future.

Recovery plan: A document drafted by U.S. Fish and Wildlife Service serving as a guide for activities to be undertaken by federal, state, or private entities in helping to recover and conserve endangered and threatened species.

Secured: Habitat of local populations are (1) owned or managed by a government agency or private conservation organization identifying maintenance of the species and its habitat as the primary management objective for the site, or (2) private land is protected by a long term or permanent conservation easement committing the landowner to conservation of the species.

Species: A group of organisms resembling one another, and includes subspecies of fish or wildlife or plants, and any distinct population segment of any species of vertebrate, fish, or wildlife that interbreeds when mature.

Species of Concern: An informal term referring to a species that may need conservation action due to declining population sizes. Similar terms include “species at risk” and “imperiled species”. Such species receive no legal protection, nor is there any guarantee that the species will be listed in the future.

Subspecies: A taxonomic rank below species, usually recognizing individuals with certain heritable characteristics distinct from other subspecies of a species.

Take: To harass, harm, pursue, hunt, shoot, wound, kill, trap, capture, or collect or attempt to engage in such conduct; may include significant habitat modification or degradation if it kills or injures wildlife by significantly impairing essential behavioral patterns including breeding, feeding, and sheltering.

Terms and conditions: Required actions described in an incidental take permit under section 10 or Incidental Take Statement intended to implement the Reasonable and Prudent Measures under section 7.

Threatened species: A species that is likely to become endangered in the foreseeable future.

Viable: A viable population has a sufficient number of individuals, reproduction by those individuals, and habitat conditions to persist over time.

Watershed: An area of land draining to a common point.

1.Will I have to pay a mitigation fee for my entire property?

No. Mitigation is proportional to project impact. Unless your entire parcel or property is impacted by development, you will not have to pay a mitigation fee on the entire property. You are required to plan your project and site placement using HCP Best Management Practices (PDF) to avoid or reduce impacts. Reducing impacts will also reduce mitigation costs.

2. How much will it cost?

The cost of mitigation depends on you. The first step is to try to avoid the protected habitat.  If you cannot avoid, the next step is to minimize the impacted area of your development.  Once you know how much total area your development will be impacting then you can use the calculation worksheet to come up with the estimated habitat conservation fee for your project. 

3. What is a Habitat Conservation Plan (HCP)?

An HCP is a large-scale mitigation plan detailing how the County will offset habitat lost to development it permits. It is the legal way to develop property in compliance with federal endangered species laws. It is also a required part of the County's application for a federal Incidental Take Permit (ITP). If the County gets a federal permit, then in most cases, its permit applicants won't have to. 

4. Why does the County need an HCP?

After the federal regulatory agency US Fish & Wildlife Service added the Mazama pocket gopher, Oregon spotted frog and other local animals to the federal Endangered Species list, County permit applicants with federally-protected habitats on their properties had to get federal permits in addition to County permits in order to build - often a long and costly process. So the County developed an umbrella HCP to cover its permit applicants who need one. Read about the federal listing of the Mazama pocket gopher.

5. What if I don't believe I have habitat on my property?

The HCP will include a process to allow applicants to demonstrate they don’t have gopher habitat on-site. Read more in the draft HCP Appendix K.

6. Am I required to participate in the County HCP?

No. It's voluntary. Permit applicants can work directly with USFWS to develop their own HCP and apply for federal permits.  

7. Will an HCP render my land unusable?

No. Just the opposite. If your property has habitat for one of the covered species, an HCP is the legal path to develop your land in compliance with the Endangered Species Act.  

8. Who approves an HCP?

U.S. Fish and Wildlife Service approves the County HCP. 

9. Who implements the HCP?

Thurston County will oversee the HCP implementation.

10. Who benefits from the County's HCP?

All permit applicants who would otherwise have to work directly with the federal regulatory agency, US Fish and Wildlife Service, which oversees the Endangered Species Act (ESA). With federal approval of the HCP, the County will be able to permit projects regulated by the federal ESA laws.


  1. Mazama pocket gopher (MPG)
  2. Olympia pocket gopher (OPG)
  3. Tenino pocket gopher (TPG)
  4. Yelm pocket gopher  (YPG)
  5. Oregon spotted frog (OSF)
  6. Taylors checkerspot butterfly (TCB)
  7. Oregon vesper sparrow (USFWS may list OVS under the ESA).


Coverage Area

  • Unincorporated areas of Thurston County.
  • Generally rural areas, and the Urban Growth Areas of Olympia,
  • Not covered: the cities of Lacey, Olympia or Tumwater, Tenino, Yelm or Bucoda 

Covered Activities

  • Residential.
  • Commercial.
  • Public services.
  • Capital projects.
  • Added Accessory Structures
  • Commercial and Industrial Development
  • County Parks, Trails, and Land Management
  • Emergency Response (gov’t. emergency management in roads for traffic accidents, hazardous waste spills).
  • Home Heating Oil Tank Removal
  • Landfill and Solid Waste Management
  • Public Service Facility Construction (schools, fire stations)
  • Residential Development
  • Septic Repair or Extension
  • Transportation Capital Projects
  • Transportation
  • Maintenance & Work in Right-of-Way
  • Utilities (overhead and underground facilities in right-of-way as well as on private property to the service meter
  • Water Resources Management (large and small stormwater drains, pipes, ponds, etc

Location / Areas

The county's federal HCP permit jurisdiction covers all the unincorporated areas of Thurston County which is generally rural areas, and the Urban Growth Areas of Olympia, Lacey & Tumwater which are under County permit jurisdiction. It does not include the cities of Lacey, Olympia or Tumwater, Tenino, Yelm or Bucoda. 

 Map of HCP Screening Area 

Map of HCP Screening Area















Map of Species Extent (or Area where Species are mapped)

Map showing outlines of where species are mapped in Thurston County
Dates Project Actions
January 2023 HCP Permitting Begins
Q4 2022 Board of County Commissioners Review & Adoption
Q3 2022 Public Feedback on the Proposed Ordinance
Q2 2022 Federal regulators approve County HCP & Issue an Incidental Take Permit
Q2 2014-2022 HCP Preparation

The County's Habitat Conservation Plan is a mitigation plan to replace the habitat lost to the building and development it permits. The County made an HCP so that its permit applicants won't have to make their own with the federal U.S. Fish and Wildlife Service. It will make permitting faster and easier for the community. If approved, the HCP will lead to a federal permit (Incidental Take Permit) which will allow the County to issue permits in areas mapped as habitat for federally Endangered Species, while also conserving habitat in a way that will ensure the survival of the listed species. 

Over the next 30 years, the County's HCP will mitigate for up to 9,500 acres of development in unincorporated Thurston County , by creating a conservation land system to preserve about 3,500 acres for the HCP-covered species. 

Related News

All News

The Thurston County Board of Commissioners is seeking public comment on proposed comprehensive plan amendments and development regulation changes for the 2024-2025 dockets. Written comments must be received by 5:00 p.m. on March 14, 2024.

The Thurston County Board of County Commissioners will hold a public hearing on Tuesday, February 6, 2024, at 3:30 p.m., or soon thereafter, to accept public comment on proposed changes to the Thurston County Code to update regulations for forest land conversion and standards for tree protection.