Wastewater tests have revealed a lot about the private lives and habits of Perth.

The WA Government has tested sewage for a range of compounds and contaminants, looking in particular to survey the city’s drug use.

Raw samples from three Perth treatment facilities have been sent to the University of South Australia for analysis.

Initial results reveal that about 31.6 kilograms of methamphetamine is consumed in the metropolitan area each week.

That means Perth’s meth use is at about 1.6 tonnes per year.

The Bunbury area had the highest concentration of the six catchment areas, with an average of 558 doses of meth each week per 1,000 people.

Perth averaged 344 doses per week per 1000 people, while Geraldton recorded an average of 314 doses.

Police say they did not realise the scale of the issue in Bunbury, and so would use the new data to inform more targeted operations.

“These tests provide us with a level of data that we have not previously had,” acting deputy police commissioner Michelle Fyfe told the ABC.

“The results that came out of Bunbury were surprising and we'll continue to work with our colleagues in Bunbury and the South West [to see] how we can disrupt and deter down there as well.”

Police Minister Liza Harvey says the data will be shared with other government agencies.

Testing will also be undertaken in Broome and 10 remote communities in coming weeks.