Planning Commission approves setback variances and tree-protection exception for 94 Palmer Lane

The Atherton Planning Commission on May 28 approved front- and rear-yard setback variances and a tree-protection zone exception for a proposed new single-family house, detached garage and attached accessory dwelling unit at 94 Palmer Lane.

Town Planner Britney Bendix and the project team explained the property is a 0.32-acre flag lot in the R1A zoning district. The applicant seeks relief from R1A front and rear yard requirements to construct a 2,961-square-foot main residence, an 800-square-foot attached ADU and a detached garage. "With the SB 9 lot split when that occurs the town has to approve future development on the new lot," Britney said while describing alternatives available under state law and local standards.

Bendix and the town arborist described six coast live oaks along the proposed driveway and garage access; the TPZ exception would reduce the protective radius around the trees to allow construction. The town arborist recommended careful hand excavation, root pruning with sharp saws on the side nearest the tree, limits on cutting roots over 1 inch, quarterly arborist reporting and use of an engineered permeable grid (easy-pave) for driveway surfaces. Planning staff included those mitigation measures as conditions.

Kelly Johnson, the project's architect, and the property owner described more than a year of work with planning staff and the arborist to refine plans, select driveway materials and minimize impacts. "We've worked with the planning department for over a year... We have worked diligently and we have spent many, many hours and resources designing a solution for this property," Johnson told the commission.

Commissioners questioned how the town's SB 9 lot-split option interacts with setbacks and tree review; staff noted SB 9 creates alternative development allowances (up to two small units in four-foot setbacks) that complicate mapping but do not eliminate the town's review responsibilities for tree protection on flag lots. Bendix said staff now flags prospective SB 9 applicants for tree protection reviews earlier in the process.

The commission approved the variances and TPZ exception and voted to include the arborist's recommended mitigation measures in permit conditions, and to require quarterly arborist reports and installation of the engineered driveway grid to reduce root damage. The Planning Department will track compliance through permit inspections and arborist monitoring.