Experts estimate the Great Artesian Basin contributes over $12 billion to the Australian economy each year.

The Great Artesian Basin (GAB) Coordinating Committee says its new report is the first to actually quantify the of GAB water.

The Great Artesian Basin is Australia's largest underground water resource, running underneath about a quarter of the country.

But even so, no whole-of-basin economic data has ever been gathered.

GAB Coordinating Committee chair Juanita Hamparsum says the range of different jurisdictions sitting on top of the basin made it extremely difficult to get good data.

“Because water is not actually reported or economic activity is not reported on the GAB areas themselves, we essentially had to go down to the NRM regions......[to get them] to provide in some cases estimates of what was being produced from the GAB water itself,” Ms Hamparsum told reporters.

“[We collaborated with] industry organisations like the Minerals Council of Australia, as well the Australian Petroleum Production & Exploration Association and various GAB jurisdictions to look at their own reporting to find out what the economic activity was.”

The two largest economic contributors in the GAB areas are mining and agriculture.

Total mining output dependant on GAB water was estimated to exceed $6 billion a year, while livestock production was found to generate $4.7 billion annually.

Irrigated agriculture using GAB water brings over $60 million a year as well.

“We will be sitting down with all the GAB government's and [groups] like the National Farmers' Federation, environmental groups and Indigenous Australians over the next eight months to develop a new Strategic Management Plan that will determine how we are going to manage the basin for the future,” Ms Hamparsum said.

“Now we have this elementary information we can make some informed decision about what we need to prioritise and protect for the future.”

Some have suggested the figures show why Great Artesian Basin Sustainability Initiative – a large-scale water-saving program – should be continued and completed.