Notwithstanding the provisions of subsection A of § 15.2-2000, any county (i) whose roads are not a part of the state secondary highway system, (ii) which has the urban county executive form of government, or (iii) is adjacent to a county which has the urban county executive form of government may, by ordinance, regulate the tracking of mud and debris upon the highways and secondary highways within the county boundaries.
Va. Code § 15.2-2022