Following three weeks of flooding in central and southern Queensland, Australia, government authorities are tallying the devastating effects: at least 28 people dead, more than 30,000 homes and businesses swamped, and an estimated $9.8 billion in damages.

Floods, which began in December 2010, engulfed 75 percent of Queensland—an area larger than Texas and California combined. A combination of heavy rainfall due to tropical cyclone Tasha as well as La Nina-related weather patterns caused the region’s worst flooding in over 100 years.

Australia’s treasurer and deputy prime minister, Wayne Swan, said the disaster could be the most costly in the country’s history.

“This is very big,” Mr. Swan told the Australian Broadcasting Corporation. “It’s not just something which is going to occupy our time for the next few months. It will be a question of years as we go through the rebuilding.”

The Daily Telegraph reported that the state’s Premier Anna Bligh told reporters in Brisbane, “Queensland is reeling…from the worst natural disaster in our history and possibly in the history of our nation…As we look across our state we’ve seen three-quarters of our state having experienced the devastation of raging flood waters and we now face a reconstruction task of post-war proportions.”

After abating in Queensland, floodwaters rose in the state of Victoria, destroying 1,400 homes in 43 towns.

Meteorologists predict additional widespread flooding in Australia during the coming months.