Residents in Australia's third largest city, Brisbane, sandbagged their homes against rising
waters on Monday, as police warned people in smaller outlying towns to be ready to abandon homes as forecasters predicted more heavy rain.

Prime Minister Julia Gillard insisted the cost of the floods would not delay a return to budget surplus in 2012-13, but JP Morgan predicted the disaster would crimp growth this year and could delay another increase in interest rates.    

The worst floods in 50 years, affecting an area the size of France and Germany combined, struck last month and have severely hurt Queensland state's $20 billion coking coal export industry. They now threaten Australia's most popular tourism destination.

 "There's a great inland sea at present," Graeme Lehman, mayor of a flood-stricken town outside Brisbane, told state radio. The towns of Kilcoy and Toogoolawah were cut off by floodwaters and there were also fears for other communities.    

Police urged motorists to stay off the roads as flash floods swept away two people in Queensland state's heavily populated southeast, home to the Sunshine and Gold Coast
tourist strips. 

 "People need to think about how to get out and if you don't need to travel, stay off the roads," said Police Chief Superintendent Alistair Dawson, referring to some of the
smaller towns. Brisbane is home to 2 million people.

Marine park officials and wildlife experts said floodwaters containing toxic farm pesticides were flowing into the Pacific Ocean, threatening Australia's Great Barrier Reef.

"Toxic pollution from flooded farms and towns along the Queensland coast will have a disastrous impact on the Great Barrier Reef's corals and will likely have a significant
impact on dugongs, turtles and other marine life," said World Wildlife Fund spokesman Nick Heath.

The Great Barrier Reef Marine Park Authority said floodwaters emptying into the sea had drifted 40 km (24 miles) offshore to the Keppel Island group, at the southern end of
the World Heritage-listed reef.

The floods have caused an estimated A$6 billion ($6 billion)in damage and economists say they will cut economic growth in 2011 and heighten inflation as food prices rise and
reconstruction begins in the nation's second largest state.

Meteorologists said monsoon rains were expected to continue all week, placing further pressure on flooded towns. "With more rain falling it could be months before the
floodwaters clear and the extent of the damage to essential infrastructure is known," said J P Morgan chief economist Stephen Walters.

J P Morgan on Monday cut its GDP growth forecast for 2011 to 3.3 percent from 3.7 percent and raised its inflation forecast to 3.8 percent from 3.2 percent. That pushed out to May from February the likely timing for the central bank's next interest rate hike.- Reuters