JOHANNESBURG - SANRAL has announced the temporary closure of the N3/N12 northbound slow lanes.
This follows the discovery of ground instability in the surrounding area, which is affecting the carriageway.
The instability has led to subsidence, causing sections of the road to gradually sink.
SANRAL Gauteng head Progress Hlahla says such undermining is often associated with illegal mining activity.
"Following the identification of the subsidence, temporary traffic accommodation measures have been implemented on site," Hlahla says.
Traffic will be diverted away from the affected slow lane while the area remains closed.
Hlahla adds that SANRAL is working with the Council for Geoscience to monitor high-risk areas.