Board upholds zoning administrator, approves ADU permit after neighbor appeal over redwood risks

The Board of Supervisors on Tuesday denied an appeal and approved a coastal administrative permit and design approval for a 1,200-square-foot accessory dwelling unit (ADU) in the Carmel area, reversing neighbors' concerns that construction would imperil nearby protected redwood trees.

Vote and outcome: The zoning administrator had approved the ADU on June 12. Neighbors Thomas and Anne Russ appealed that decision, citing potential root and structural risks to a grove of redwoods that adjoins their property. After testimony from competing arborists and a lengthy hearing, the board voted to deny the appeal and approve the coastal administrative permit and design approval; the vote was announced as carrying with the motion recorded as carried.

Why it mattered: The appeal focused on two questions: whether the county's review process complied with procedural requirements and whether development at the proposed location would create unacceptable risk to significant redwoods and to neighbors.

Evidence and expert analysis - Applicant testing and reports: The applicant engaged three certified arborists and provided three project-specific arborist reports, including excavation test pits. The applicant's arborists and project engineer recommended a bridging (floating) foundation and a tree-monitoring program during construction. - Appellants' concerns: The appellants submitted independent analyses and argued that excavation and construction disturbance near the redwood grove could damage structural roots and increase hazard risk. The appellants asked the board to require relocation of the ADU to a less-sensitive on-site location. - Staff findings: Housing and Community Development staff reviewed the site materials, including the arborist reports and excavation tests, and concluded the proposed site was the least impactful location on the parcel and that protective conditions could mitigate root impacts. Staff added a condition (Condition 4) requiring arborist monitoring and tree-root protections for excavation within 10 feet of the ADU footprint. - Environmental Health context: Not central to this appeal but discussed elsewhere in the meeting, Environmental Health noted local ground and septic constraints in parts of the Carmel area as background to coastal permitting decisions.

Board discussion and public comment Both sides presented arborist testimony at the meeting. Appellants argued the standard used to evaluate hazard risk was insufficiently rigorous for mature redwoods on a small residential parcel; the applicant countered that multiple independent arborists found the trees healthy and structurally sound and that a bridging foundation, monitoring and mitigation measures reduce risk.

Conditions and monitoring The board's approval incorporated the zoning administrator's conditions and the additional tree-and-root protections staff recommended: pre-construction protective measures, arborist monitoring during excavation when within 10 feet of protected trees, and final inspection reporting to ensure trees remain stable after construction.

Bottom line: The board found the record adequate to support the zoning administrator's decision and accepted the mitigations and monitoring described by staff and the applicant's consultants. The board denied the appeal and approved the coastal administrative permit.

Ending: The county will monitor construction as required by conditions of approval and the appellants may seek other remedies available under the county code if future impacts occur; staff emphasized the permit includes monitoring and protective steps.