Thurston County panel backs 'support' language for 5% rural growth aim, directs ADU and conservation policy changes

Thurston County commissioners on Dec. 2 directed staff to revise the county’s comprehensive plan language so it “support[s] a sustainable development pattern that reduces the share of new growth in rural areas to 5% and focus[es] future development within urban areas,” and they instructed staff to prepare implementing code language before final action on Dec. 16.

The board’s vote followed a lengthy staff presentation and legal briefing that, according to staff, advised using the word “support” rather than “establish” to avoid triggering immediate, state‑level challenges that could require the county to enact zoning changes before it has completed implementing steps. Vice Chair Wayne moved the direction and the board voted to incorporate the softened language into the draft ordinance.

Commissioners also spent more than an hour on a contentious package of implementation items tied to the comp plan. After public comments and a planning commission recommendation, the board directed staff to draft code provisions to allow rural detached accessory dwelling units (ADUs) of up to 1,000 square feet with flexibility for proximity to the primary dwelling and measures to limit additional impervious surface (such as encouraging use of existing driveways rather than creating secondary driveways).

Commissioners debated multiple tradeoffs: some said more permissive ADU rules advance housing equity for rural residents and allow families to provide in‑home care, while others warned that loosening rural development rules risks undermining the 5% rural‑growth aim. Planning staff said septic, well placement and critical‑areas protections will continue to constrain where ADUs may be feasible in unincorporated areas.

The board also unanimously directed staff to reduce regulatory barriers to cluster (conservation) subdivisions to help conserve farmland, habitat and water resources; staff showed examples demonstrating how clustering homes and conserving open space can lower environmental impacts compared with conventional rural subdivisions.

On energy rules, staff asked to delay new code provisions for battery energy storage system (BESS) facilities until early 2026 in order to work through emerging technical and stakeholder questions. Commissioners voted to table that piece and schedule follow‑up work early next year.

What’s next: staff will circulate draft ordinance and code language to the board and the public before the Dec. 16 meeting. That packet will include the revised 5% language, the proposed ADU language and the cluster‑development changes for final consideration and possible adoption.

Speakers quoted (from the meeting): Vice Chair Wayne said the board should “support a sustainable development pattern that reduces the share of new growth in rural areas to 5% and focus future development within urban areas.” Planning staff warned that legal precedent gives reason to favor “support” language rather than language that would immediately require enactment of zoning changes.

The board’s decisions are procedural directions to staff; formal adoption of the comprehensive plan and implementing code changes remains a future, formal vote.