N.C. Gen. Stat. § 153A-218
A county may establish, acquire, erect, repair, maintain, and operate local confinement facilities and may for these purposes appropriate funds not otherwise limited as to use by law. Subject to the holdover provisions in G.S. 7B-2204, no person under the age of 18 may be held in a county confinement facility unless there is an agreement between the county confinement facility and the Division of Juvenile Justice allowing the housing of persons under the age of 18 at the facility or a portion of the facility that has been approved as a juvenile detention facility by the Division of Juvenile Justice. A juvenile detention facility may be located in the same facility as a county jail provided that the juvenile detention facility meets the requirements of this Article and G.S. 143B-819.
N.C. Gen. Stat. § 153A-218