S.C. Code Ann. § 56-5-490: Intersection defined.

An "intersection" is the area embraced within the prolongation or connection of the lateral curb lines or, if none, then the lateral boundary lines of the roadways of two highways which join one another at, or approximately at, right angles or the area within which vehicles traveling upon different highways joining at any other angle may come in contact.

When a highway includes two roadways thirty feet or more apart, every crossing of each roadway of such divided highway by an intersecting highway shall be regarded as a separate intersection. In the event such intersecting highway also includes two roadways thirty feet or more apart, every crossing of two roadways of such highways shall be regarded as a separate intersection.