Contractors from Dunedin-based company Pro Civil Construction Limited were hard at work in Pitt St on Thursday.
Dunedin City Council capital team leader Kieran Trainor said the work was to stabilise a slope where a slip occurred during a heavy weather event in July last year.
After the slip, contractors removed additional overhanging material in September.
Now, contractors were drilling into the slope to install steel rods and a mesh facing, which would then be covered with vegetation, he said.
"We took immediate action following the slip in July 2022 to clear the debris and assess the safety of the road and houses above.
Pitt St was expected to reopen on December 23, but depending on ground conditions may need to be completed in the new year, which might involve a short road closure, Mr Trainor said.