Sydney lashed by heaviest rainfall in 5 years

Australia's sodden southeast was hit with new flooding Thursday as Sydney was lashed by its heaviest rainfall in five years and the inland town of Forbes was inundated.

Large tracts of New South Wales state are under water, with Sydney feeling the force of a La Nina weather system as an estimated 119 millimetres (4.7 inches) of rain fell on the city -- the highest daily total since 2007.

"There has been very, very heavy rain and some very strong winds," a Bureau of Meteorology spokesman said. La Nina conditions typically bring higher-than-normal rainfall.

The downpour sparked widespread flash flooding, caused havoc with bus timetables, forced the closure of railway lines and dozens of roads, and prompted power cuts to at least 2,000 homes.

Several flights from Sydney were delayed or cancelled while there were fears that hundreds of boats on Sydney Harbour could sink after filling up with rainwater, NSW Maritime officials said.

"We've had a hell of a rain event," NSW roads minister Duncan Gay told reporters. "It is a weather event the likes of which many of us have never seen before. It's that one-in-a-hundred year event that you hear of."

Reports said authorities had been called out to more than 1,000 incidents in the city.

Further inland, Forbes, in the state's west, was cut in three by flooding with some 1,000 people ordered to leave their homes as the Lachlan River continued to rise.

Heavy rain and flooding has hit three eastern states throughout the week, sweeping two men to their deaths after they attempted to cross waterways in cars, inundating hundreds of homes and causing millions of dollars in damage.

"We're totally surrounded in the CBD by water," Forbes mayor Phyllis Miller told national broadcaster ABC.

Parts of rural Victoria state are also struggling, with residents from the northern town of Nathalia evacuated as floodwaters threatened to breach both its main levees.

Treasurer Wayne Swan said it was too early to establish the cost of the floods, although some estimates have put it as high as Aus$1 billion ($1.05 bn, Dh3.89bn).

But Swan expects there will be a significant impact on the New South Wales agriculture sector.

"It's far too early to tell what the economic cost of these floods will be.  Many parts of the state (NSW) are still under water," he told ABC radio.

"We won't know the damage to the public infrastructure. We won't know the damage to the private infrastructure. So what we've got to do is assess that as quickly as we can and make sure we get help to those most in need."

Floods in eastern Australia last year that claimed more than 30 lives and left damage bills of some Aus$ 6 billion.