One lane on Fussell Street will remain closed until the end of this week due to a mineshaft opening up near the Victoria Street intersection.
The City of Ballarat was notified of changes to the road surface on Monday afternoon.
A small hole was discovered on the road and a traffic management plan was put in place while the mine was assessed on Tuesday.
Contractors are on site today to excavate and re-fill the mine opening.
The concrete required for filling mineshafts is a special mix of accelerants and Micro Rebar reinforcement.
The mineshaft has been benched with steel beams for extra reinforcement for the concrete. This is standard procedure when filling mineshafts.
The southbound lane of Fussell Street will remain closed until the end of this week while the concrete sets.
Historical mining activity in the goldfields region saw mineshafts capped with Red Gum timber. These caps are getting towards the end of their life.
The City of Ballarat deals with one or two instances of mineshafts opening up each year.