The Northland Forestry Industry is helping workers kick drug habits but as a result, some are turning to alcohol as an alternative.
Mental health workers say the region needs more support to deal with the fallout of shifting the problem.
Forestry trainer Jack Johnson says workers have succeeded in being drug free but have now taken up "drinking huge amounts of alcohol to fill the void" and says it’s brought on "other issues".
Others have switched from marijuana to meth to beat the drug tests.
"Once we get the boys off thc's they seem to be able to use meth that is out of their system in two to three days," Mr Johnson said.
For many workers the issues that lead to drug and alcohol abuse run deep.
"If you live a life full of poverty and oppression, you’re trying to get some ‘feel good’ in there." Drugs and Addiction counsellor Teina Piripi told 1 NEWS.
"So many of us have intergenerational abuse through drugs and alcohol."