Washington County planning commission weighs allowing rural accessory dwelling units

WASHINGTON COUNTY, Ore. — Washington County planning staff presented an issue paper on June 18 outlining options to allow accessory dwelling units (ADUs) in the county’s rural residential zones and asked the Planning Commission for policy guidance on how strict any future ordinance should be.

The county’s Land Use & Transportation senior planner, Todd Borkowitz, told the commission the state allows two distinct rural ADU types: a "historic dwelling ADU," which converts a qualifying historic dwelling into an ADU when a new primary dwelling is built, and a "rural ADU," which creates a new accessory unit on a lot that already contains a single detached dwelling. "The state allows 2 distinct types of ADUs," Borkowitz said as he summarized statutory limits and county implications.

County staff presented where the state’s minimum standards would permit those ADUs, and asked commissioners to weigh in on six policy questions: whether to allow one or both ADU types in rural residential districts; whether to treat the two types under the same standards (including limits on vacation rentals); whether to prohibit ADUs in groundwater-restricted areas unless served by an outside water source; whether ADUs should be barred on properties subject to nuisance orders; whether primary and accessory units must share the same water source; and whether historic dwelling ADUs should meet the same fire-protection requirements as other rural ADUs.

Why it matters: rural ADUs…