A staggering amount of methylamphetamine is being shot up, smoked and snorted around Australia, with the latest national sewerage testing revealing it remains the illicit drug of choice.

The Australian Criminal Intelligence Commission's fourth National Wastewater Drug Monitoring Program report released on Thursday showed an overall increase in illicit drug use across the country compared to the previous report.

More than 8.3 tonnes of meth was consumed in Australia between August 2016 and August last year, which federal Law Enforcement Minister Angus Taylor said was an extraordinary amount.

"More than all other hard drugs combined," Mr Taylor told reporters in Mandurah, a town south of Perth selected for the planned welfare recipients drug testing scheme.

"We know we have a very serious issue with methamphetamines."

The highest meth consumption was detected in Adelaide and regional Western Australia.

Mr Taylor said meth was "devastating" country areas where only a decade ago hard drugs were rarely seen.

"That ice was produced locally even five, six years ago," he said.

"It's now being imported through major, very well organised, very sophisticated global criminal networks."

WA Police Commissioner Chris Dawson agreed meth was increasingly being smuggled in from overseas.

"We're not finding as many clandestine laboratories," he said.

In WA, where vast tracts of uninhabited coastline are attractive for international drug traffickers, more than 1.4 tonnes of meth have been seized in the past 10 months.

"That's more than we've ever seized in that sort of time frame," Mr Dawson said.

He said he was not sure why meth was so popular in the state but pointed out NSW also had a taste for stimulants, namely cocaine, which wasn't as available in WA.

Mr Taylor was asked to speculate why WA had such a strong appetite for meth.

"Maybe it's about the remoteness, maybe there's an element of what we've seen in regional Queensland where there's higher levels of fly-in, fly-out workers - that seems to have an impact," he said.

"We don't have strong evidence on this."

Federal MP for Canning Andrew Hastie, whose key election campaign platform was waging war on ice, gave examples of how drugs were wreaking havoc in once-quiet country towns.

In Dwellingup - a tiny WA timber and fruit growing town with a population of just a few hundred people - residents had told him addicts were making it somewhat "ungoverned".

And in Mandurah, a medical service is helping youths as young as 12 to stay clean.

"We're seeing inter-generational drug use," he said.

"Parents are addicted, they have young children and of course they're in a household where they see drug usage so they unfortunately get caught up in it."