S.C. Code Ann. § 31-3-760

But the territorial jurisdiction of a housing authority of a county shall include the territorial jurisdiction of any housing authority of a city if a resolution is adopted by the council of the city, and also by the housing authority of the city if it shall have been theretofore established, declaring, as provided in SECTION 31-3-400, that there is a need for the county housing authority to exercise its powers within such city.