Twin Falls County, ID Swimming Pools & Spas: Fencing & Safety Requirements (2026)

County Code section 8-9-6, Swimming Pools, sits in Title 8's general zoning provisions and applies countywide to any pool that is not completely enclosed within a building's solid walls, whether an in-ground, above-ground or other constructed pool on residential, agricultural or other zoned property in the unincorporated county. The section requires two things at once: a setback of at least five feet from every property line, and a complete perimeter fence or wall at least five feet high around the pool. The barrier cannot have any opening larger than thirty six square inches, a limit meant to keep small children from squeezing through gaps in the fence or wall, and any gate in that barrier must carry both a self-closing device and a self-latching device so the enclosure closes itself after someone passes through.

The section does not create a separate permit process by its own text, but pool construction still runs through the county's building permit and zoning review under Titles 7 and 8, and inspectors checking a building permit for a new pool confirm the setback and fence height as part of that review. Because the rule is written into the zoning title rather than a stand-alone building or health code, both the Zoning Administrator and the Building Department can act on a complaint about a missing or undersized pool barrier in the unincorporated county outside the cities' areas of impact.

A property owner replacing an existing pool fence, or installing a new pool, needs to keep the five-foot height and thirty-six-square-inch opening limits in mind at the same time as the five-foot property-line setback, since all three numbers come from the same sentence of section 8-9-6.