Va. Code § 15.2-2639
Any county may, upon approval by the affirmative vote of the voters of the county voting in an election on the question, elect to be treated as a city for the purpose of incurring debt and issuing bonds under this chapter. If a county so elects, it will thereafter be subject to all of the benefits and limitations of Article VII, Section 10 (a) of the Constitution of Virginia and all provisions of this chapter relating to bonded indebtedness applicable to municipalities, but in determining the debt limitation for such county under § 15.2-2634 there shall be included, unless otherwise excluded under Article VII, Section 10 (a) of the Constitution of Virginia, indebtedness of any town or district in that county empowered to levy taxes on real estate.
Va. Code § 15.2-2639