Australians spent $9.3 billion last year on cocaine, meth, MDMA and heroin, with cocaine and meth rising from previous years.
Analysis of wastewater shows how much of each of the drugs is being consumed around the country, underlining the size of the black market.
The Australian Criminal Intelligence Commission on Wednesday released its sixth National Wastewater Drug Monitoring Program report, which monitored 58 wastewater stations in July and August 2018.
It estimates more than 9.6 tonnes of methylamphetamine was consumed in Australia in the year to August 2018, along with four tonnes of cocaine, 1.1 tonnes of MDMA, and more than 700 kilograms of heroin.
"It is astounding that Australians waste over $9.3 billion a year on drugs. This is money people could be spending on legitimate goods for themselves and their families," commission chief executive Michael Phelan said on Wednesday.
The report also looked at cannabis consumption, which regional Australia uses at double the rate of city dwellers.
In the second year of the testing program, the commission found cocaine and meth consumption were up, but MDMA and heroin were down
Mr Phelan said a positive sign is the drop in fentanyl use across regional areas.
The report covers 56 per cent of the population, which equates to about 13 million people.
The tests look for 13 substances, including nicotine, alcohol, and opiods.
