Police have arrested a woman in Caterton after finding 660 grams of methamphetamine during a pre-planned search.
That amount of meth is equivalent to about 33,000 doses and worth approximately $230,000, police said.
The bust may have prevented up to $730,000 worth of social harm, detective senior sergeant Philip Skoglund said.
About $37,000 in cash was also seized.
The 24-year-old was at a gang-affiliated address during the search warrant, they said.
She has been charged with possession of methamphetamine for supply and is due to appear in the Masterton District Court on Wednesday.
Further arrests were likely, police said.