Methamphetamine use in Ashburton has remained relatively low since a crackdown known as Operation Mastiff put a serious dent in a local drug supply ring in 2022.

However, cocaine is now being routinely detected, although at low levels.

Wastewater testing data obtained through the Official Information Act shows Ashburton had the lowest use of meth in Canterbury during 2023.

Wastewater in Ashburton is tested every second month. Near the start of 2022, the tests showed a meth use rate as high as 755mg a day per 1000 people in March, and 579mg a day per 1000 people in July 2022.

This fell to 91mg in September 2022 and 114mg in November 2022 after Operation Mastiff, and for 2023 use remained low with an average of 126mg a day per 1000 people over the year.

Meth use in Ashburton plummeted by more than 80% in 2022, following the crackdown.

Operation Mastiff involved more than 100 police officers and members of the Armed Offender Squad swooping on Ashburton to execute 29 search warrants around the district in early September 2022, as part of a nationwide crackdown on illegal gang activity.

Police found drugs with a street value of $70,000, including meth, cannabis, LSD and other restricted drugs. They also seized nearly $20,000 in cash and several weapons and imitation firearms.

A total of 18 people were arrested in the operation and the police laid over 160 charges. At the time, then-Senior Sergeant Leigh Jenkins said it was the biggest drug bust in this area in more than a decade, and possibly the biggest operation of its type in Ashburton ever.

Ashburton senior sergeant Janine Bowden this week said police were pleased that wastewater testing for methamphetamine had remained low following Operation Mastiff in 2022.

"Police remain focused on targeting the supply of illegal drugs, wherever they are coming from, with the aim of reducing harm in our communities.

"We can all play a part in reducing the social harm and misery that drugs cause by reporting any suspicious activity so that the police can conduct enquiries and hold offenders to account.”

National Drug Intelligence Bureau detective inspector Timothy Chao said methamphetamine, MDMA and cocaine were the only drugs routinely detected in Ashburton in 2023.

Testing for ketamine and several synthetic cathinones was added in April but these drugs were not routinely detected in Ashburton, he said.

"In 2023, drug use in Ashburton was low for all commodities when compared with other sites in Canterbury and nationwide."

Meth use in Ashburton remained low throughout 2023. MDMA use was variable but remained below the national average, he said.

In 2022, Ashburton had the lowest average MDMA consumption per capita in Canterbury, even though MDMA spiked for a few months following Operation Mastiff.

The average consumption of MDMA in Ashburton in 2023 was slightly lower than in 2022 - at an estimated 161mg a day per 1000 people and well below the national average of 282mg.

However, cocaine use is now at a level where it is routinely detected in wastewater samples, which wasn't the case a year ago.

Cocaine use in Ashburton is 6mg a day per 1000 people - the lowest in Canterbury and well below the national average of 79mg.

Meth use in Canterbury

In 2022, estimated meth consumption per capita was highest in Timaru (above 400mg per 1000 population), followed by Ashburton, Christchurch and Rangiora (below 300mg per 1000 population).

For 2023, consumption per capita remained highest in Timaru, followed by Christchurch, Rangiora and Ashburton. Use in Ashburton and Rangiora were both below 140mg.

However, all the Canterbury sites tested were below the national average consumption, of 497mg per 1000 population.

If you have any information relating to illegal drugs, or if you feel unsafe or have concerns about dangerous, illegal or suspicious behaviour, call the police on 111. For non-urgent concerns, call 105 or visit www.police.govt.nz/use-105 to report an incident online.

By Sharon Davis