Report 21 of the National Wastewater Drug Monitoring Program covered sampling from August 2022 to August 2023. Nationally, 62 wastewater sites were monitored, covering 57% of the Australian population.

Since the last report, methylamphetamine, cocaine and 3,4-methylenedioxymethylamphetamine (MDMA) consumption increased tangibly. More than 16.5 tonnes of methylamphetamine, cocaine, heroin and MDMA combined was consumed between August 2022 and August 2023, representing a 17% increase in consumption of these drugs from the previous year. When THC (cannabis) is included, more than 30 tonnes of the 5 illicit drugs was consumed nationally.

The 1.5 tonne increase in national methylamphetamine consumption is of considerable concern, due to the significant community harms caused by the drug. Of the estimated $12.4 billion spent on methylamphetamine, cocaine, MDMA and heroin between August 2022 and August 2023, methylamphetamine accounted for 85% of this expenditure.