Ada County commissioners approve rewrite of Title 8, add standards for centralized solar facilities

Ada County commissioners voted unanimously on Oct. 28 to approve application 202402581, a repeal-and-replace of Title 8 of the Ada County Code that updates the county zoning ordinance and adds specific standards for centralized power (solar) facilities.

The ordinance rewrite was presented by Stacy Dupree of Ada County Development Services, who said staff made scrivener edits throughout the document, added private-property language requested by the Planning and Zoning Commission, and created a reserved Veil Creek overlay chapter for later detail. Dupree said the draft removes multifamily as a conditional use in limited office zones and removes a requirement that properties connect to city services within 300 feet if a septic system fails. She also described specific standards for centralized power facilities, including siting limits and financial surety requirements.

"We removed the language requiring connection to city services within 300 feet if a septic system system fails," Dupree said, noting that staff also added a definition for prime farmland and standards to prevent siting solar arrays on high-value agricultural land unless the applicant demonstrates the land is not economically viable for farming.

The new section on centralized power facilities requires applicants to provide irrevocable financial assurance sufficient to cover full decommissioning and reclamation costs before issuance of grading or building permits. Dupree outlined acceptable forms of security (standby letter of credit, bond, or other security acceptable to Ada County), an evergreen automatic-extension clause for continuous coverage, and periodic review and adjustment of the security amount at least every five years or sooner if the facility undergoes material modification.

Staff also proposed inspection and enforcement rights for the county, successor-liability provisions that bind decommissioning obligations to the land, and trigger conditions requiring decommissioning after 12 months of continuous nonoperation unless the owner demonstrates intent to resume commercial operation. Dupree said the county reserves the right to draw on the financial assurance to complete decommissioning, including administrative, legal, engineering and contracting costs.

Dupree described the criteria by which prime farmland could be shown to be unsuitable for agricultural use — for example, a qualified soil scientist's determination of limiting conditions, documented sustained low crop yields verified through farm records or USDA Risk Management Agency data, or an enterprise-budget profitability analysis demonstrating net returns per acre well below regional benchmarks.

Commissioners clarified that the rewrite is not solely a solar ordinance but a comprehensive update of Title 8. After discussion, a commissioner moved to approve the clean copy of the ordinance and order its publication; the motion was seconded and carried by voice vote with all commissioners saying "aye."

The ordinance will take effect following the county's normal publication process and any other steps required by county code.