Burst pipe sends 150 million litres down the drain

A rupture in one of Brisbane's main pipelines has sent than 150 million litres of drinking water down the drain.

The pipeline burst at Anstead around 3am, flooding roads and gardens in the city's western and south western suburbs.

But by early afternoon, normal supply had been restored to hundreds of homes.

At one stage, the torrent on Mount Crosby Road forced Energex to switch off an electricity transformer. Danny Donald from Energex said power was re-routed to prevent blackouts.

Dozens of suburbs around Anstead - as far southwest as Wacol and Inala - and south to Moorooka and Salisbury were without water or had low pressure until midday.

LinkWater said about 150 megalitres of water was lost.

General manager Andrew Moir said the company took over management of the pipeline from Brisbane City Council on July 1 last year.

"It is a main that was built in the late 1960s .. these pipes should last 90 to 100 years," he said.

All mains are inspected every six to 12 months but Mr Moir couldn't say when the burst pipe was last checked.

Brisbane City Council and LinkWater crews are draining the main to see what caused the rupture leak.