Note: There is an issue with basemap roads without a city and name being listed as in another state (most commonly Georgia or North Carolina). Double-check the state attribute of each road you edit! You can also use the Validator script to highlight roads with a state other than SC (custom check; template: ${state}, regex: !/^South Carolina$/).
Road typing
South Carolina follows the national guidelines for road types.
Locking
| Segment Type | Urban | Coastal | Rural |
|---|---|---|---|
| Freeway | 5 | ||
| Ramp | Highest lock of connected segment | ||
| Major Highway | 3 | 4 | 2 |
| Minor Highway | 2 | 3 | 1 |
| Primary Street | 1 | 2 | 1 |
Naming
State Highways should be named as SC-XXX. This includes both primary and alternate names for a road.
State Secondary Routes are state-maintained roadways that are not part of the state highway system. This number is typically signed with a small black sign at any such roadway. These should be named as S-##-XXX, where ## is the number of the county (alphabetical order, see chart above; Abbeville is 1, York is 46) and XXX is the route number (e.g. 18); the full name for route 18 in York county would therefore be S-46-18. This name should only be set as an alternate road name. In rare cases, a road will have this number and no name; in this case, it should be named "Rd XXX", with the full number as an alternate. For example, S-3-497 in Ulmer is named "Rd 497" with the alt name "S-3-497". Consult with the State Manager before changing a name to the "Rd XXX" system.
Both state highway numbers and state secondary route numbers can be easily accessed online with SC Street finder.
County Road numbers in South Carolina are usually not easily available and never signed; however, in places where they can be found more easily we use CR-XXX to mark them. Note some interstate exits will label a road as being "County Rd XXX". This does NOT mean that this is a county route; usually, they are state secondary routes.