County staff says pools currently count toward floor-area-ratio; board asks for ordinance amendment

Alameda County planning staff told the Transportation & Planning Committee on Jan. 6 that the county zoning ordinance currently defines swimming pools as a building, which means pool area can be included in floor-area-ratio (FAR) and other building-area calculations. The chair asked whether the county can remove pools from FAR calculations; Rodrigo, a planning staff member, said yes — but only through a zoning ordinance amendment that would go to the Planning Commission and then back to this committee and the full Board of Supervisors.

The issue stems from an older local ordinance and the local interpretation of California building code language. Rodrigo said state building-code definitions describe a "building" and a "structure" broadly, leaving room for local interpretation; the county’s definition of building currently includes pools. He said staff could strike the language that classifies pools as a building so that pools would not be included in FAR or other building-area calculations.

Why it matters: supervisors said constituents have asked for the change, and that the rule affects both rural and urban unincorporated areas. President Meili and other supervisors said the change should be circulated to affected Municipal Advisory Committees (MAXs) before Planning Commission review so community voices are heard. Rodrigo estimated that routing the item through the MAXs and the Planning Commission could take longer than three months depending on schedules; supervisors set a stretch goal of returning the item in roughly three to six months.

Supervisors also asked about related issues: whether pool water can be used for fire suppression and whether the county has examples or precedent. Rodrigo said the fire chief’s guidance is that pool water is not part of a building’s water supply for sprinklers; property owners can apply for "alternative means" approvals, but Cal Fire must sign off in State Responsibility Areas (SRA). Staff said two alternative-means approvals have been granted in the unincorporated area in the last three years and agreed to return with a 10-year record of requests and approvals.

What happens next: supervisors directed staff to prepare a zoning-ordinance amendment process, coordinate with affected MAXs, and return with timing and a public outreach plan. The committee did not take formal action; staff will bring a recommendation back for public consideration.

"Pools are defined by the county zoning ordinance as a building," Rodrigo said. "If the board deems it should be reconsidered, we would process a zoning ordinance amendment through the Planning Commission and the board."