Northland has the highest rate of methamphetamine use and of the powerful opioid fentanyl in the country.
And a worker in the drug rehabilitation field in Northland says more rehab services and a greater awareness of them would help reduce the problem of methamphetamine - or P as it is also known - in the region.
A snapshot of the region's drug use has been released by police and Police Commissioner Mike Bush said authorities are continuing to build a clearer picture of New Zealand's drug use, with the first results of the National Wastewater Testing Programme.
Results are now available for the first three months of nationwide wastewater testing, which covers around 80 per cent of New Zealand's population, including testing at Whangārei and Kerikeri wastewater treatment plants.
The drugs that have been tested for are methamphetamine, cocaine, heroin, MDMA and fentanyl.
The preliminary results, from November 2018 to January 2019, show methamphetamine is the most commonly detected illicit drug nationwide, with approximately 16kg estimated to be consumed on average each week. The detected average use of methamphetamine translates to an estimated $20 million per week in social harm.
Regional variations in drug use have also been identified with methamphetamine use shown to be most prevalent per capita in Northland, MDMA in Canterbury and cocaine in the wider Auckland region.
In Northland it's estimated that 1100mg of methamphetamine is used in one week per 1000 people, well up on the next highest rates - 990mg per 1000 in the Eastern District, 800mg in the Bay of Plenty and 780mg in Auckland.
But when it comes to fentanyl - a powerful opioid up to 100 times more potent than morphine and many times that of heroin - the survey shows 1.7mg of the drug is used per 1000 people a week in Northland, with most of the drug discovered in the Kerikeri wastewater plant where 3 per cent of total drugs found was fentanyl.
Fentanyl is an opioid used as a pain medication and together with other medications for anaesthesia and Kerikeri's large elderly population could be behind the figures. But fentanyl is also used as a recreational drug.
Major Sue Hay, director of the Salvation Army's Bridge Addiction Service in Northland, said the service had seen an increase in people wanting help to overcome methamphetamine issues in recent years and the reasons behind why people used the drug were complex.
The service is run in Whangārei, Kaitaia and Kaikohe and sees about 500 people a year in Whangārei alone and Hay said people wanting to do better for their children was the main reason they sought help to overcome their addiction or methamphetamine use.
Bridge is part of the Te Ara Oranga project - an initiative between Police and Northland DHB - designed to reduce methamphetamine use and refer users to rehabilitation services.
''We see the people who are seeking help. The overwhelming reason for them seeking help is that they want to do better for their children. They realise life is spiralling out of control and they want to stop the spiral and leave a better legacy for their children,'' Hay said.
Sometimes the clients had been referred to Bridge by Oranga Tamariki or the Probation Service while others had reached that point themselves through a "lightbulb" moment.
Hay said a few years ago alcohol was the main substance the programme dealt with, but not anymore since the rise of methamphetamine.
''Now 40 per cent of people in Whangārei have more than one substance to deal with and 18 per cent of people have methamphetamine as their primary issue.''
She said Odyssey House and Ngati Hine also provided rehabilitation services along with the NDHB's detox unit, Timatanga Hou at Dargaville Hospital, but more were needed in the region, particularly an after-hours centre.
Hay said stress, poverty, mental health issues and domestic violence were some of the reasons behind people turning to drugs.
NZ Drug Foundation executive director Ross Bell said most of the country's methamphetamine was imported from overseas, mainly Asia, but research showed that Northland has easier access to the drug than the rest of the country.
''Previous studies and this confirm that methamphetamine use in Northland is higher than any other part of the county. It's the easy availability of meth in Northland combined with the social issues driving use - poverty, high unemployment, particularly among youth, lack of housing, etc - that are behind the high use.''
Bell said there was a lot of meth in the world right now, with importation replacing the traditional meth labs that were traditionally used to make the drug here.
In June 2016, almost half a tonne of methamphetamine was found by police after it was landed on Ninety Mile Beach, but Bell was not sure if Northland was a major importing centre for the drug, but it could be behind the region's high use.
''It could be part of the explanation that there is large importation through Northland, but one of the big issues is that there is easy supply of meth up there - and we are being told it's easier to get there than cannabis, which really concerns me,'' he said.
''Meth has a totally different effect than cannabis.''
And the solution to the region, and country's meth problem, is already being worked on in Northland, Bell said.
''Northland is already leading the way with Te Ara Oranga. It works and should be the gold standard for the whole county. In Northland police are referring (meth) users to health services through the DHB and it is making a difference.''
More rehabilitation service would also help, he said.
Police Commissioner Mike Bush said that, while the results prove the benefits of nationwide wastewater testing, it is only a snapshot of the bigger picture that long-term testing will lead to.
"These early results give us an idea of the potential for this type of data and, as testing continues, it will enhance our understanding of the demand and supply of illicit drugs and the associated harm caused in our communities.
"The long term results will help Police and other agencies make informed decisions around drug treatment services, and initiatives to combat organised crime groups dealing in methamphetamine and other drugs.
"We expect that after 12 months of nationwide testing a robust baseline measure of illicit drug use will be established.
"Three months of results, however, are only an early indicator of illicit drug use levels in New Zealand and cannot yet be used to draw any firm conclusions," he said.