Wastewater tests of Auckland and Christchurch treatment plants have revealed traces of cocaine, methamphetamine and MDMA.
However, authorities overseeing the new pilot programme have so far failed to find any detections of heroin and designer drug alpha-PVP.
The insights were among baseline results of the first three rounds of testing in the programme, which began in December and is being overseen by the New Zealand Customs Service, Ministry of Health and New Zealand Police.
The programme, targeting wastewater sites in Auckland and Christchurch, aims to provide a better picture of the prevalence of drug use in New Zealand communities.
Results showed weekly totals of 734 grams, 648 grams and 730 grams of methamphetamine were detected respectively in December, January and February in Auckland, compared with weekly readings of 731 grams, 458 grams and 798 grams in Christchurch over the same months.
MDMA appeared in weekly quantities of 111 grams, 97 grams and 51 grams in Auckland over the three months, and 261 grams, 142 grams and 120 grams correspondingly in Christchurch.
Cocaine turned up in totals of 92 grams, 40 grams and 49 grams in Auckland, and in 6 grams and 25 grams in Christchurch in January and February only.
The first quarter's results would build a baseline for future testing, authorities said.
"As this is the first time New Zealand Government has undertaken this type of programme, we need to ensure that we have an appropriate baseline to compare future results from," said police assistant commissioner Bill Searle.
"While this report does include three months' worth of data, it is difficult to make meaningful analysis of the results until further data is available."
However, Searle said, it could be seen from the results that there was no alpha-PVP or heroin being found in either testing site.
"The absence of these drugs in the areas being tested is good news for agencies."
Ministry of Health director of mental health Dr John Crawshaw said the programme would be the first time authorities had access to quantitative data that would allow for a more accurate picture of drug use in those communities where the testing is conducted.
"The programme will also show if an area sees changes in drug use patterns as well as the introduction of a drug in an area where it has previously tested negative," Crawshaw said.
"This information will help government consider responses to the needs identified in the results."
The programme is separate from a Massey University-led pilot study that recently found relatively high levels of methamphetamine in tests taken at wastewater treatment plants servicing 1.3 million Aucklanders.