A report commissioned by an anti-mining group says huge mining projects in central west Queensland will have a huge impact on groundwater storage there.
AAP reports more than 34 open cut and 11 underground coal mines are proposed along a 270km stretch of the Galilee basin.
The report for the Lock the Gate Alliance says the mine projects combined will have an enormous impact on groundwater levels.
Author Tom Crothers suggests they could also interfere with the Great Artesian Basin.
The report says federal and state governments have failed to assess the cumulative impacts the mining projects will have on groundwater relied upon by farmers and towns.
"Groundwater drawdown will significantly reduce the ability for surrounding graziers and towns to supply their water needs," it says.
Mr Crothers estimates the mines would consume a total of 1354 billion litres over project life estimates of between 30 and 90 years.
AAP reprots this is the equivalent of 2½ Sydney harbours removed from underground storages.
The alliance says mining approvals in the area should be suspended until the government undertakes further studies.
"Our communities depend on groundwater - it's our lifeblood," said spokeswoman Ellie Smith.