14 September, 2023 10:35
1953 - nearing completion of dual siphon pipe install

Urban Utilities has begun a major renewal of one of our city’s most impressive, yet hidden, pieces of engineering – the historic Bulimba-Hamilton siphon – which lies 60 metres below the surface of the river.

Built by the same company that constructed the Story Bridge, the siphon stretches under the river from Bulimba to Hamilton and consists of two large wastewater pipes inside a tunnel.

Urban Utilities Chief Executive Officer Paul Arnold said the $54 million major city project involved replacing one of the pipes inside the tunnel.

“As part of our planning for the future, one of the pipes is being replaced after serving our city well for nearly 70 years,” he said.

“The new pipe sections will be lowered into the tunnel from the Hamilton side of the river, while the old pipe will be removed from the Bulimba side.

“It’s a once-in-a-generation renewal for one of our city’s most important pieces of essential infrastructure.”

Urban Utilities’ unofficial historian and Head of Environmental Solutions Col Hester said original construction on the siphon began in 1948 using traditional tunnelling methods. 

“It was challenging work with two shifts of eight men cutting through around 10 metres of rock per week, under very wet and noisy conditions,” he said.

“These workers put their bodies on the line and the enormous effort that went into building the siphon cannot be understated.”

Mr Arnold said it was important to understand how vital the Bulimba-Hamilton siphon still is to the community 70 years on.

“The siphon has the unique job of transporting wastewater from thousands of homes and businesses on the southside of Brisbane under the river to our Eagle Farm Pump Station, where it’s then pumped to Luggage Point for treatment,” he said.

“It’s projects like these that show how much goes on behind the scenes to remove and treat all the wastewater from 1.6 million customers across our region.”

Mr Arnold said the second pipe in the siphon would continue to transport the normal daily wastewater flows while the other pipe was being replaced.

“We live in a climate of extremes here in South East Queensland and we plan for wet weather. During heavy rain, stormwater infiltrates our wastewater network, increasing flows,” he said.

“In the event of potential wet weather, we will be managing excess flows through a temporary emergency relief point.”

The project, which is being carried out by our delivery partner Fulton Hogan, is expected to be completed in early to mid 2024.

For the latest information, visit urbanutilities.com.au/HamiltonBulimbaSiphon 


About Urban Utilities
Established on July 1, 2010, Urban Utilities is one of the largest water distributor-retailers in Australia, providing water and sewerage services to more than 1.5 million residents in South East Queensland. Our 14,384km2 geographic area is made up of the five local government areas of Brisbane, Ipswich, Lockyer Valley, Scenic Rim and Somerset.