A municipality may not alter any state highway facility without the prior approval of the department, and any use or restriction made by a municipality of a highway or highway right of way for municipal utilities, parking, or other purposes is subject to prior approval of the department by encroachment permit.
Alterations of state highways by municipalities
S.C. Code Ann. § 57-5-840, under Title 57, Chapter 5.
S.C. Code Ann. § 57-5-840