Dr. Cara Whitaker, land use conservation and policy section manager for the Washington Department of Fish and Wildlife, told the Lynnwood City Council on Oct. 15 that the city’s required update to its Critical Areas Ordinance (CAO) should designate riparian ecosystems as fish and wildlife habitat conservation areas and set riparian management zone (RMZ) widths based on the “site potential tree height at 200” or a 100‑foot minimum where full RMZs are not practical.

Whitaker said the Growth Management Act requires cities to designate and protect critical areas, incorporate the best available science and aim for “no net loss of ecosystem functions and values.” She described WDFW guidance in two volumes: Volume 1 (riparian functions) and Volume 2 (riparian management and delineation). “Riparian ecosystems are one of our highest priority habitats statewide,” Whitaker said, and WDFW recommends RMZs be sized by site potential tree height at age 200, using on‑line mapping tools or field validation.

The recommendation departs from the Department of Natural Resources’ traditional water‑type buffer approach that assigns wider buffers to larger, fish‑bearing streams. Whitaker said WDFW’s best available science review found “no scientific justification for protecting non‑fish‑bearing streams less than fish‑bearing streams,” and that non‑fish streams nonetheless provide pollution removal, connectivity and inputs that support downstream fisheries.

City staff and WDFW outlined how RMZ widths would be delineated on a site: from the ordinary high water mark or active channel out to the larger of (a) the site potential tree height at 200 or (b) a 100‑foot pollution‑removal distance. Whitaker said a 140‑foot example RMZ gives substantially better bank stability than a 25‑foot buffer, and that in some urban settings a 100‑foot minimum is a reasonable next‑best choice when existing conditions preclude fully functioning RMZs.

Council members asked how no‑net‑loss is measured and whether lower‑scale uses such as trails are a concern. Whitaker said area is a basic metric but not always representative; metrics depend on the critical‑area type and long‑term monitoring is important for compensatory mitigation. She said trails typically do not significantly degrade riparian functions unless paved or motorized.

Council member John Decker asked whether homeless encampments upstream can affect streams; Whitaker replied she had not studied that topic directly but said trash and human waste can pose pollution risks and affect wildlife, and that upstream conditions do flow into Lynnwood’s ponds and creeks.

On timing, Carl Almgren, Lynnwood community planning manager, told council staff have discussed the update with the Department of Commerce and “we will be out of compliance likely for 2 months at the beginning of the year” if the ordinance is not adopted by the end‑of‑year deadline. Almgren said the city prefers to take slightly more time to get the reorganization and the new methodology right rather than rush a substandard update; staff included an update schedule in the council packet and plan developer outreach, including a developer roundtable.

Council members pressed staff about specific sites that may be affected by the change in methodology. Almgren said staff has begun discussions with prospective applicants for several sites, including the former Best Auto/UPS parcel on Highway 99, and noted the Sound Transit transit‑oriented development site has a piped stream that Sound Transit’s engineers found unlikely to last 50 years, a factor that would trigger daylighting and RMZ considerations.

Almgren said Lynnwood uses field verification for presumed stream locations: GIS and WDFW site‑potential tree‑height mapping provide preliminary information, but qualified professionals must verify stream type and RMZ delineation for permit reviews. He also said vesting applies: expired entitlements must meet then‑current codes; Northline Village’s development agreement preserved an earlier pipe analysis for that project’s phases.

Why it matters: the CAO update will change how development and mitigation near streams are evaluated, affect active and piped stream projects such as the Sound Transit TOD and several private redevelopment proposals, and could limit access to certain Commerce planning grants if the city remains late on mandatory updates.

Council members and WDFW staff acknowledged trade‑offs between protecting critical areas and accommodating new housing. Whitaker said WDFW aims to help jurisdictions find “win‑win solutions” that support both habitat conservation and responsible development.

Looking ahead: staff intends to present a draft ordinance that incorporates the best available science, coordinate with developers about transition timing, and pursue outreach and monitoring programs to track whether no‑net‑loss is achieved over time.