The full work programme will begin on June 7.
Last month it was reported that the rotting material inside the plant would start to be removed.
The council's head of Three Waters, Helen Beaumont, said crews would be working 12 hours a day, six days a week to get the job done by September - three months earlier than expected.
"Southern Demolition undertook the trial removal of the material for us in December 2021 so they are aware of the huge job ahead of them. They are going to pull out all the stops to complete the removal work as quickly as possible.
"It's a complex task as the trickling filters have eight-metre-high (three-storey) concrete walls and there is about 26,000 cubic metres - about the volume of 10 Olympic swimming pools - of material to remove."
But Beaumont warned the putrid odour may get worse before it gets better.
"Unfortunately, there are days when the smell could get worse as material deep inside the trickling filters gets exposed to the elements and starts rotting.
The cost of removing the material from the trickling filters will be funded from an interim insurance payment the council has received.
It comes after Christchurch City Council approved a support package to assist those living nearest to the wastewater plant.
Residents who live within the area bounded by Buckleys and Pages Rds, State Highway 74 and Linwood Ave are able to apply for $200 through one of four community agencies to help deal with the impacts of the fire.
About 3300 homes are in the area.
But earlier this week, the council said due to high demand, the community providers were already running low on Prezzy cards.
