Canberra's underground fat fight

Canberra's underground fat fight

As affluent as Canberra is, we'll never produce a fatberg to rival the one dredged up in a London sewer.

For 10 days recently workers wrestled the 15-tonne ball of congealed food fat, dubbed Britain's biggest ever fatberg, which was mixed with sanitary wipes into a lump as big as double-decker bus.

Instead of waiting for a heavy contender to erupt from the depths, ACTEW Water sends four jet-rodder trucks to the four corners of the city to blast fat.

They're armed with 100 metre high pressure hoses with cutters attached, which tear into suburban pipes and hot spots around restaurants and grease traps.


A team leader with ACTEW Water, Wayne Eccleston, has found 300mm of fat caking the inside of 6 to 14 metre wet wells stationed at height intervals in Canberra's gravity-fed sewer system.

White as lard and laced with sanitary wipes, the fat has to be shovelled out. Some wells are scraped out every six months. At Fyshwick, one is cleaned every four weeks.

"A lot of people don't care about the next person who comes along. They are getting worse, not better," Mr Eccleston said.

Gunk from kitchen sinks and toilets collects from people's ignorance of what happens to hot liquid fat once it flows into cold pipes below. It congeals.

Pouring hot water and detergent doesn't cut through it.

ACTEW water industry operator Paul Ricketts said commonsense was in short supply when everything from ping pong balls, underpants and (accidentally) false teeth were flushed down the toilet.

"People think it's a magic place, where you press the toilet button and everything disappears," Mr Ricketts said.

The contents flows from the home through a 100mm diameter pipe to the property's boundary, where it continues on through a 140mm pipe.

When lumps of fat and cloth catch on tree roots the outcome stinks. Human waste quickly backs up into streets, gardens or even homes.

ACTEW Water annually cleans around 300 kilometres of sewers across the capital, enough pipes to stretch from Canberra to Sydney.

Mr Ricketts said one resident in a street full of people could block a sewer if not taking a little care around the kitchen sink.

Cleaning equipment is fed down manholes, which collect dangerous gas from rotting organic material and sometimes gases leaking from fuels. Workers are not allowed down them.

It's a job for specialists in the complex fat fight below the ground.


Planting trees and shrubs to hide man holes and access pipes to sewers increases risks of blockages.

"They cause a lot of trouble in the newer suburbs. Plenty of residents think they are doing the right thing, but are causing problems," Mr Eccleston said.