SA Water has started testing Naracoorte’s sewerage network for any incorrect or illegal stormwater connections as well as broken or cracked sections of pipe, by discharging small amounts of artificially generated smoke into the town’s system.
The method – commonly used by water utilities around Australia – will help SA Water identify where stormwater is entering the sewers, which can contribute to overflows following a heavy rain event.
After putting smoke into the sewer network, the utility will look for escape points such as stormwater downpipes on the side of a building’s roof guttering, or from the road surface of a broken inspection point lid.
SA Water’s Senior Manager of Capital Delivery Peter Seltsikas said Naracoorte was selected for testing due to the high number of sewage overflows at the local treatment plant’s pump station after heavy downpours.
“Our ongoing monitoring indicates there could be points in the network that are receiving excess stormwater flows after a rain event, and we’re taking a proactive approach to identify sources of intrusion,” Mr Seltsikas said.
“While it’s normal to have a level of stormwater infiltration, recent events have significantly raised the volume and flow of sewage in Naracoorte’s network and overwhelmed our pump station.
“The increased flow also elevates the risk of overflows to the environment or onto a person’s property and we want to help minimise the chance of this to ensure our sewers are able to continue protecting public health.
“All the information we gather as part of these inspections will inform a range of solutions, such as replacing or repairing sections of sewer main, or working with property owners on remediation options.
“We appreciate that some people may not be aware they have an illegal stormwater connection on their property, but it’s important the issue is rectified to reduce the risk of overflows and keep our sewers healthy.”
The odourless grey-like smoke, which is similar to that used at concerts or for special effects, is harmless to people, plants, animals and the environment, does not stain and dissipates within a few minutes.
Mr Seltsikas said the inspections will take place between 7am to 5pm each day.
“The local community has been given advanced notice of the work, and our contractor PPS has also advised the Country Fire Service, in case any smoke is observed,” he said.
“During the work, we may need to access easements along the roadside, as well as driveways and front yards.
“There will be no disruption to our local customers’ sewerage service as a result of the work, and they can keep using taps and other plumbing fixtures as per usual, as smoke will not come out where there is a water seal, such as in a toilet.”
