Think a sewage explosion in your home sounds far-fetched? Think again. SA’s recent drought conditions can make pipe problems more common. Find out why – and what you can do to stop them.
Ever heard of a “poonami”? It’s as messy – and smelly – as it sounds.
Picture a sudden eruption of raw sewage in your garden, patio, or (worst-case scenario) even inside your home. Yep, we warned you it wasn’t pretty.
Unfortunately, thanks to South Australia’s current drought, thirsty tree roots are on the move, desperately seeking moisture from any available source – including inside your sewerage pipes.
And as these tree roots infiltrate pipe joints, they can cause blockages and overflows, leading to the dreaded poonami.
But here’s the good news: there’s plenty you can do to keep your pipes – and your garden – safe.
With some handy online tools from SA Water, poonami-proofing your home has never been easier.
Wait, why is this happening?
It’s simple: trees need water, especially when rainfall is well below average – exactly what’s happening now across much of South Australia.
“Tree root intrusion into underground pipes is the leading cause of sewer blockages in our state-wide network, contributing to around 60 per cent of all blockages annually,” says SA Water’s Senior Manager Field Operations, Colin Bell.
“Particularly during dry and warm periods like we’re experiencing now, tree roots actively seek out water through joints in pipes, which can lead to blockages or even sewage overflows.”
The eastern suburbs and foothills of Adelaide are particularly susceptible, thanks to their abundant greenery – but the risk exists everywhere.
Colin says SA Water uses proactive measures to reduce the risk of blockages in the network, including an ongoing sewer cleaning program that uses high-pressure jet rodders (specialised machinery) to dislodge and cut through any pipe blockages caused by tree roots, as well as sending CCTV cameras into pipes to inspect their condition and smart sensors to monitor flow.
However, blockages in SA Water’s pipe network during March and April this year were up 33 per cent compared to the same period in 2024, jumping from 378 to 576 incidents.
Don’t plant yourself into trouble
Thinking about giving your garden a fresh look or starting from scratch in a new place? Hold off on planting until you’ve checked the underground situation.
SA Water’s Healthy Pipes online map is a life-saver here. This handy tool shows where the sewerage mains and connections for your property are located underground.
It also tells you what your pipes are made of, which is crucial because vitreous clay pipes are far more vulnerable to tree root intrusion than newer PVC pipes.
Colin encourages South Australians to use the Healthy Pipes tool – by guiding you to plant larger or aggressive-rooted trees safely away from pipes, you’re drastically reducing the risk of future blockages.
Picking the right plants
Did you know not all trees are equal when it comes to causing sewer chaos? Some species, especially larger trees with aggressive root systems, can wreak havoc.
SA Water’s Tree Planting Guide helps you choose the right tree species for the right spot, ensuring your green space remains poonami-free.
The guide includes easy-to-follow schedules identifying which trees can safely be planted closer to pipes and which should be avoided altogether.
Pro tip: plants like bottlebrush and native shrubs are usually safe bets – they’re pipe-friendly and drought-tolerant!
But what if I’m renting? Other ways to avoid the dreaded blockage
Good news, renters – you’re not powerless against poonamis. You might not control your landscaping, but your flushing habits can save you from major headaches.
Trees aren’t the only culprits behind poonamis – you also need to watch what you flush in your toilet and pour down your sink.
Putting anything other than the four Ps – paper (toilet), pee, poo and products with proof they’ve passed the Australian and New Zealand Flushable Product Standard – down the dunny risks these items getting stuck in your internal pipes and tangling with thirsty tree roots.
Items like non-flushable wet wipes, paper towels and tissues are not designed to easily break down in water, while pouring cooking fats, greases and oils down the drain can build up and congeal in your internal pipework and SA Water’s sewer pipes in the street.
SA Water’s crews have also encountered bizarre items like footballs, superhero costumes, and even rubber chickens in its sewers!
Over time, all of these items can clump together with tree roots that have made their way into your pipes – causing a blockage to form quicker, which will restrict the flow of sewage.
If it can’t flow out from your property’s pipes to SA Water’s sewer network, it will eventually come back up and cause an overflow in your garden, or worse, inside your home.
What if the worst happens?
If a poonami strikes, you’ll need to act swiftly. If the issue is within your property’s internal pipework, contact a licensed plumber immediately.
If you think the blockage is in SA Water’s infrastructure, call their 24/7 Customer Care Centre on 1300 SA WATER (1300 729 283) straight away.
However, no one wants things to get that far, so prevention really is the best approach.
Keep your garden – and your pipes – happy
Whether you’re a homeowner landscaping your dream garden, or a renter keen to avoid trouble, we can all do something to poonami-proof our homes.
Take advantage of SA Water’s free resources, choose your greenery carefully, and be mindful of what goes down your dunny and drains. A little care now can prevent a big stink later on.
For more information, check out SA Water’s Tree Planting Guide and their Healthy Pipes online map here.
