The big stink: This is how much raw sewage is being dumped into the Brisbane River

Complications with a “once in a generation” under-river infrastructure project are forcing officials to dump millions of litres of raw sewage and stormwater directly into the Brisbane River.

A total of 540 megalitres has been discharged in the past 18 months and the practice is set to continue for months, if not years.

The problem stems from the $210 million Bulimba-Hamilton Siphon Renewal Program.

The project involves restoring a tunnel built between 1948 and 1954, used to transport sewage from a catchment of about 150,000 residents on Brisbane’s southside to the Luggage Point Resource Recovery Centre on the north, for processing.

The project hit a complication in January 2024 when a pipe within the tunnel burst.

Urban Utilities chief executive Paul Arnold.Credit: Nine News

Now, during heavy rain, sewage and stormwater must be discharged into the river to prevent the entire system overloading.

Nine News obtained the data from the Department of Environment, which issues permits for the releases.

Urban Utilities chief executive Paul Arnold said the sewage was filtered through a grid and was usually “heavily diluted” by stormwater.

“During sustained rainfall, our network can’t manage our stormwater that finds its way into our network, creating the need for us to discharge into the Brisbane River.

“That has been ongoing since the commencement of the project and will continue until we’ve completed the replacement of both pipes within the siphon.

“We signalled and communicated to community groups, to the Department of Environment, that there will be times, with the reduced capacity of the siphon, that there will be discharges.”

Arnold said the discharges were from a point in Morningside and all complied with regulations.

“Every time there’s a discharge, we take that very seriously,” he said.

“We want to make sure the community is protected, so we issue emails and communicate to river users in the area that there has been a discharge.

“We ask them not to make contact with that area of the Brisbane River between Vic Lucas Park at Bulimba, all the way up to Colmslie Beach Reserve.”

Brisbane City Council is required to publish the results of its water quality monitoring program.

A reading detecting 500 colony-forming units per 100 millilitres of water suggested “there may be a significant risk of high levels of illness transmission” in the water.

In the weeks after Cyclone Alfred, readings detected more than three times that amount in Colmslie, West End and Indooroopilly.

Resident Adam Bowden began a community group to advocate for cleaner waterways, after bacteria levels spiked in Cabbage Tree Creek, near the Sandgate Wastewater Treatment Plant.

He said the revelations of the discharges into the Brisbane River were “absolutely disgusting”.

Adam Bowden started a community group after local waterways were found to be contaminated.Credit: Nine News

“Honestly, we cannot continue to let this happen. I am mind-blown by this data,” he said.

“I knew the situation was bad but this is worse than I expected.

“We want people to come to Brisbane and see a beautiful, clean city. If we continue on the path we’re going, we’re not going to see that.”

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