The Big Dry, also known as The Millenium Drought, began in 1996. Conditions worsened when there was no significant rainfall between two separate droughts in 2002 and 2007. Australia was finally declared drought-free in April 2012.
Southern areas of Victoria and South Australia and north-eastern areas of Tasmania started experiencing periods of rainfall deficiency in 1996. Conditions improved temporarily in these states by around 1999-2000.
By August 2002 severe rainfall deficiencies developed across much of eastern Australia following poor autumn and early winter rains. Parts of south-west Western Australia were deficient in growing season rainfall for the third successive year. All states were affected. January 2003 was one of the driest months on record. Most of Queensland, New South Wales, Victoria and parts of Northern Territory, South Australia and Western Australia were affected. In February, Queensland and New South Wales received some relieving rainfall; however June rains were still well below average.
In January 2004 the Bureau of Meteorology announced 18-month rainfall deficiencies in part of eastern and northern Australia. This made it to 23 months by June. In general, the south-east areas of Australia received below-average rainfall for most of the previous eight-year period. Good rains in November removed or decreased rainfall deficiencies over many areas, with some deficiencies persisting in southern parts of Western Australia and central Queensland.
The year 2005 saw rainfall deficiencies in South Australia, New South Wales, Victoria and Tasmania. Victoria and South Australia had the driest autumn on record. Good rains in October and November improved conditions in Queensland. In the years 2006-2007, Australia experienced an El Nino event. June 2006 saw poor to record low autumn rains for the sixth year in south-eastern Australia. A distinct turn for the worse occurred in August when near-total failure of late winter and spring rains occurred. In June 2007 some easing of severe drought conditions occurred from autumn rains in New South Wales, north-west Victoria, Tasmania, southern parts of South Australia. Some areas of east Queensland, southern Victoria (near Melbourne) and west Western Australia missed out. May 2008 was the driest May on record and rainfall deficiencies were evident for a 12 month period in eastern South Australia, southern Northern Territory and parts of Victoria and Western Australia.
November 2008 rainfall was above to very much above average over much of Australia. The rain largely cleared short-term rainfall deficiencies, especially in the Northern Territory, South Australia and Western Australia; however, average to below-average falls in western Victoria and south-eastern South Australia maintained deficiencies in these areas.
The autumn of 2010 was the first autumn with above-average rainfall since 2000 in Victoria and the Murray Darling Basin. Serious to severe rainfall deficiency continued in the western area of Western Australia, some shortfall in southern Tasmania and north-eastern New South Wales. Due to excessively dry soils, significant rain was required to alleviate the shortage of water across the country resulting from prolonged drought conditions.
December 2010 saw Australia record the wettest spring for the months of September to November with an average of 163 mm of rain beating the previous record by 23 mm. The widespread above-average rainfall again missed the south-west corner of Western Australia which experienced a record dry year. Northern and eastern parts of the country continued to receive above to very much above average rainfall, with Queensland, New South Wales and the Northern Territory all recording their wettest spring on record. All states recorded above-average rainfall for spring, with all states except Tasmania recording totals placing them in their ten wettest springs on record.
Despite the above-average rainfall by mid-2010 water storages had still not returned to pre-drought levels. Irrigated industries such as the Murray-Darling Basin were particularly affected where water storage levels fell to 17 per cent of capacity in 2003 and remained below pre-drought levels until late 2011.
By mid-2010 the Australian Government had paid approximately $4.4 billion in direct drought assistance to affected farmers.
The Federal Government declared Australia drought-free for the first time in more than ten years in April 2012.