Work is under way to construct temporary bypass pipework at Finger Point Beach in Port MacDonnell to enable maintenance on the outfall pipe that safely discharges treated wastewater from SA Water’s nearby treatment plant.
During this stage of work – which is expected to take around eight weeks – a small section of the beach will be closed at times to enable construction to be safely undertaken with signage on site providing this notice to the local community.
The Finger Point Wastewater Treatment Plant treats around five million litres of sewage per day from residents and businesses in Mount Gambier, before it is discharged into the Southern Ocean by the outfall pipe.
SA Water’s Senior Manager of Capital Delivery Peter Seltsikas said recent inspections of the pipe found minor cracks and leaks, with the bypass infrastructure ensuring the plant can continue to operate during works.
“Like wastewater treatment plants operated around the world, our Finger Point plant safely discharges highly cleaned and thoroughly treated wastewater 100 metres off the beach via the outfall pipe, which is located under seawater and encased in concrete,” he said.
“While this particular section of pipe has operated reliably for more than 50 years, we have recently identified a few minor cracks that we need to repair to ensure it continues to remain in sound condition for years to come.
“The plant plays a critical role in protecting public health by taking wastewater away from Mount Gambier for treatment, and taking the pipe offline for this work requires a temporary bypass to keep the facility operational.
“Our crews have been working to install the above ground pipeline since last month and are now at the stage where they’ll begin constructing the new section that will cross the beach and head out into the ocean.
“The 450-millimetre-diameter poly pipe will be anchored parallel to the existing outfall pipe’s alignment and run along the beach’s surface until it reaches the water, where it transitions to a buried pipe of a slightly smaller size with a stainless steel diffuser to release our treated wastewater.
“Construction activities will be carefully planned to accommodate the challenging site conditions associated with working in water, with infrastructure pre-fabricated where possible to allow our installation to progress as quickly as possible given our need to align work within low tide and low swell times during the day.
“Once the bypass is up and running, our operators will switch the flow to the new pipework to maintain service while enabling our crews to commence investigations on the pipe and prepare a methodology for repairs.”
