Don’t rush to flush

Projects, 2/01/2017

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Our maintenance contractors maintain the pipes that take wastewater from your home to the wastewater treatment plants. Their job is twofold: carry out routine maintenance to ensure the wastewater network is working as it should, and attend emergency callouts, where blocked wastewater pipes have caused overflows.

When you tell us about a wastewater overflow, our contractors will clear blockages and clean and sanitise the area.

“For us, undertaking routine maintenance is really important,” says Lui Vete, a maintenance  serviceperson with our central networks team. “By flushing pipes with high pressure water we can clear things that have started building up in there, breaking up blockages before they cause problems.”

But when it comes to emergency call-outs and overflows, Lui says the main culprits are things people flush down toilets or pour down sinks at home.

“Rags and wipes are some of the biggest issues,” he says. “Most people just throw them away in the closest thing – the toilet!”

Most wastewater pipes are only 100 millimetres (four inches) in diameter and are not designed to carry anything other than wastewater and bio-degradable products, like human waste and toilet paper. But last year, 84 per cent of overflows during dry weather were caused by people flushing rubbish down the toilet, pouring cooking fat down the sink and tree roots that had grown into pipes.

Items like rags, sanitary items, wipes, dental floss and nappies don’t break down in the wastewater network. Instead, they form large, impenetrable clumps that can block pipes. When this happens, undiluted wastewater can overflow into private properties and the wider environment, polluting your property and Auckland’s streams and beaches.

The good thing is it’s easy to reduce these kinds of overflows – just be aware of what you are putting down your toilets and sinks. Only human waste and toilet paper should be flushed down the toilet; everything else goes in the bin.

To find out more about overflows, read our latest Tapped In newsletter.