The sinkhole was a result of a water leak in a water pipe crossing the freeway.
Due to the close proximity of the sinkhole to the inner edges of the road and the subsidence of the road surface on the middle lane on the southbound carriageway, the department decided to close off two of the southbound and one of northbound lanes as a precautionary measure.
This has led to major congestion in both directions, leading to frustration among motorists.
According to the department, in a bid to reduce the inconvenience caused by the lane closures, additional lanes will be constructed on the outer shoulders of the slow lanes. This will commence within the next week to ensure that two lanes are open to traffic in both directions at all times.
A temporary additional lane will also be constructed to bypass the sinkhole on the southbound carriageway to alleviate the traffic congestion before the end of July.
The recently resurfaced shoulder lane on the southbound carriageway will be used as a second lane until the construction of the additional lane has been opened to traffic by the end of August.
"The results of the preliminary geological tests that have been carried out the past week has indicated that extensive repair work will be required to rehabilitate the sinkhole area, fill the underground cavities under the road (the lanes that have been closed off) and reconstruct the section the freeway affected by the sinkhole.
"The scope of the remedial work required has been determined by the Department, and a tender will be issued within the next three weeks," said the department.
It added that due to the extent of the work, technical complexity of the project, traffic and safety consideration, a contract period of between four and six months will be required for completion.
"The department would like to thank motorists for their patience in the last two weeks and requests motorists to be patient and adhere to the speed limit in the designated area," the department said.
