The rebuild of Christchurch’s Wastewater Treatment Plant is on schedule and within budget, councillors have been told.

At a council workshop on Tuesday, council staff updated elected members on progress with the new Activated Sludge Plant.

The project follows the fire in November 2021 that destroyed the plant’s trickling filters.

That forced the council to put in place an interim treatment system that has caused ongoing environmental and community issues.

In September 2024, councillors agreed to replace the lost capacity with a conventional activated sludge secondary treatment process, backed by an $85 million insurance settlement.

Officials said the site has now been cleared, design work completed, and tenders released to shortlisted contractors. A contract for construction management has already been awarded.

The project remains on time and on budget, with a main construction contract expected to be awarded by the end of this year.

Site establishment and ground improvement work will follow.

Council staff also highlighted the use of 3D technology and a collaborative design approach which they said had accelerated progress.

Councillor Yani Johanson told chrislynchmedia.com: “I welcome the release of the designs for the activated sludge plant.

“This is a significant step towards the replacement of the trickling filters. The odours continue to adversely impact the local community so maintaining positive progress on this project as a top priority is essential. I look forward to the construction contract being awarded, the local residents being briefed, and the building work beginning as soon as it possibly can.”

A further update will be provided once a contractor is confirmed and construction is underway.