Unitywater has started smoke testing parts of its wastewater network in Queensland, to identify breaks and openings in the pipes.
The work is part of the water utility’s annual program to find and fix locations where stormwater can enter the wastewater network and cause overflows after heavy rain.
The smoke testing technique will also help identify loose seals on maintenance holes or incorrect plumbing connections.
“During heavy downpours, incorrect connections can direct large volumes of stormwater into the wastewater network and overwhelm it, increasing the chance of wastewater overflows to the environment and back up into homes,” Unitywater executive manager strategic engagement Joshua Zugajev said.
“While stormwater-related surges aren’t the only reason for overflows, they’re something that we can avoid if both Unitywater infrastructure and customer pipework’s are correctly installed and maintained.”
The process involves blowing non-toxic, non-flammable artificial smoke through the wastewater network, before it emerges from designated sewer vents or through cracks that need repair or incorrect connections that need to be realigned.
“The last phase of the program inspected over 20,000 properties across the Nambour region and uncovered over 500 plumbing defects,” Zugajev said.
“The identification and rectification of these issues has resulted in a 10 per cent reduction in stormwater inflows in the catchment, which means less chance of homes in that region experiencing an overflow.”
Subscribe to Trenchless Australasia for the latest project and industry news.