(Bloomberg) -- A huge clean-up operation is under way inthe Australian state of Queensland after a powerful cyclone sweptthrough the region, tearing roofs off buildings, downing trees and forcing tourists to bunkerdown at luxury island resorts.

The Whitsunday Islands in the heart of the Great Barrier Reefsuffered “substantial damage” when Cyclone Debbie swept throughyesterday, and roads have been cut off around coastal towns, statePremier Annastacia Palaszczuk told ABC television Wednesday. AndrewWillcox, a regional mayor, told the broadcaster the town of Bowenlooks “like a war zone.”

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Flooding expected

Severe weather warnings remain in place even after Debbie wasdowngraded to a tropical low overnight as it moved inland, withdamaging wind and heavy rain expected to cause flooding, accordingto the Bureau of Meteorology. The storm halted at least 20 percentof coal output from the biggest producing basin in Queensland, withBHP Billiton Ltd. and Glencore Plc suspending operations.

Previous storms across the region have flooded mines, swampedmachinery and washed away rail tracks, leading to price spikes amidcrimped supply.

The Port of Townsville, which handles approximately $21 millionin trade per day, said shipping would resume this morning, after itevacuated vessels and personnel on Monday. North QueenslandBulk Ports said the Port of Mackay remains closed after abreakwater was damaged.

Limited injuries reported

Authorities said there had been more than 800 calls for emergencyassistance in the state and the number would rise oncecommunications are restored to isolated communities.

The Daydream Island resort, which has 200 guests and 60 staff,was running low on water, while authorities were trying to makecontact with Hayman Island, Palaszczuk said. There were limitedreports of injuries in storm-affected areas, the premier told theABC.

The sugar industry is bracing for damage that could run intotens of millions of dollars on lost yield from sugar cane that’s“been knocked over by a steam roller,” Paul Schembri, chairman ofindustry group Canegrowers, told the broadcaster.

About 9 million tons of sugar cane was impacted by the cyclone,however most of that is salvageable, he said.

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