Locals flee as Brisbane braces for peak

Floodwaters inundating Brisbane have prompted mass evacuations and brought the metropolis to a standstill, as authorities warn of worse to come.

The Brisbane River was at 4.3m late on Wednesday afternoon and rising, causing chaos in the CBD as people were ordered out, roads were cut, and might and other crucial services were shut down.

Some 400 residents have taken shelter at evacuation centres but authorities require that come to grow dramatically as Brisbane braces for the top of 5.2m at 4am (AEST) on Thursday.

The predicted peak has been revised down from 5.5m, which would have exceeded the charge experienced during the devastating 1974 floods.

'It is good tidings that that bloom has been revised down slightly,' Queensland Premier Anna Bligh told Network Ten on Wednesday.

'But this is yet a major event, the metropolis is often bigger, much more populated and has many parts under flood that didn't yet be in 1974.

'We are even look at an outcome which will cripple parts of our city.'

Authorities have opened three more evacuation centres, bringing the number to five, and boosting capacity from 6,500 to a whopping 16,000.

'We are planning on upping the ante,' Lord Mayor Campbell Newman told reporters on the banks of the swelling Brisbane River, expressing concern at the act of residents who seem to be dragging their heels.

'People really shouldn't muck around, if they're on the flood map, if your streets on the list . make the determination to get out.'

Authorities still consider the floods will strike some 19,700 homes and 3,500 businesses but were unable to put a name on the list of properties damaged as of late Wednesday.

They said some 35 out of 50 at-risk suburbs have been affected so far, including New Produce and St Lucia where evacuations have been taking place throughout the day.

Transport throughout Brisbane has taken a major hit, with 106 roads closed, including the Inner City Bypass, the Ipswich Motorway and Coronation Drive.

Officials predict 1,657 roads will end up partially or completely flooded.

The floods have turned Brisbane's usually bustling CBD streets eerily quiet, with the bulk of shops, offices and buildings closed because of a forced power shutdown.

A bulk sub-station in Tennyson was inundated, cutting power temporarily to another 50,000 residents in Brisbane's inner west.

It takes the entire amount of Queenslanders without electricity to 180,000.

Trains are working on a limited schedule, buses have stopped, while CityCat and CityFerry services were off on Tuesday because of the risk posed by junk in the river.

Popular riverside restaurant Drift Cafe was swept away, just one of various pieces of large debris creating drama on the Brisbane River, along with boats and steel pontoons.

Hundreds of sightseers were lining Kangaroo Point to demand photos and head out rubbish in the water.

Officials are set to ruin the Moggill ferry, which has come loose on the Brisbane River and threatens to damage bridges as it is swept along on the torrent.

Brisbane City Council has decided to destroy a popular floating riverwalk, while a determination has yet to be made around an Island Party Boat which is also out of command on the water.

After E-coli was ground in the water at Chinchilla, officials sought to allay fears of pollution in Brisbane, telling residents the urine was good to drink.

Hospital services have been kept to a minimum, with all non-urgent surgery cancelled and only emergency departments open.

The catastrophe is being widely felt, with garbage collections in Brisbane put off for a week, phone lines affected and Australia Post warning of significant delays to mail services across the state.

Authorities have warned flood levels may not retreat for 3 to 4 days.