The majority of roads today are created as part of a land sub-division and vested to the respective council under Section 223lg of the Land Titles Act upon deposit of the plan of division.
In the early days of South Australia small subdivisions were created with "private roads" these roads on the whole have been taken into the respective Council ownership under the "Roads Opening and Closing Act 1991".
There are areas however where small subdivisions/townships were surveyed and deposited in the Land Titles Office where the roads were never built and quite often have been used by the contiguous owner as their own.
It is possible for the contiguous owner of the road to apply for the road to be closed (if not already done so) and arrange for the road to be consolidated into their contiguous land.
Optima are happy to discuss and advise you on your individual situation.