The Atherton Planning Commission on July 23 approved a special structures permit for 236 Camino Al Lago to allow a basement that extends beyond the first‑floor footprint and tightly spaced retaining walls needed for a sunken tennis court and court curbing.

Town planner Brittany Bennix told the commission the project’s basement would extend approximately 415 square feet beyond the first‑floor perimeter (within the allowable special‑structures review), and the proposed retaining walls would be closer than the separation standards in AMC section 17.46xx because the walls are low curbs under 3 feet to preserve tree protection zones. Staff concluded the elements are generally below grade and reduce above‑grade impacts and recommended approval.

Applicant representatives from Swatt | Architects and Surface Design explained the intent: locate the main building near the center of the nearly two‑acre parcel, retain perimeter heritage trees, locate most of the basement under the main floor (95% under the primary footprint), and place low retaining curbs around the sunken sports court to avoid encroaching on tree drip lines. The applicant said the small retaining curbs are generally under 30 inches and function more like curbing than tall retaining walls; structural review will occur during building permit review.

Staff and the applicant told commissioners the town arborist had already reviewed tree impacts and that locating the low curbs closer together avoids encroaching into key tree protection zones. Commissioners asked about structural safety; staff explained building‑permit structural review will address that stage.

The commission voted to approve the special structures permit, finding it met criteria for neighborhood privacy, reduced visible structure above grade, and compliance with general plan and zoning objectives.

Why it matters: The permit enables a large estate redevelopment while keeping most new built area below grade and attempting to retain existing perimeter trees by using low curbs and basement geometry rather than taller visible structures.

Details: The proposed residence is roughly 18,275 sq. ft. with ancillary structures including a pool house and a detached ADU. The applicant noted about 95% of the basement area is under the main floor, with the requested 415 sq. ft. of basement beyond the first‑floor footprint; the tennis‑court curbing proposed is generally under 30 inches. The commission approved staff findings and the motion to grant the special structures permit.

Next steps: Applicant to proceed to building permit review where structural calculations for the basement and retaining walls will be reviewed and where staff will continue to coordinate with the town arborist on tree protections.