More than 300,000 people are being potentially supplied drinking water that doesn't have the necessary protective barriers.
The country's water regulator, Taumata Arowai, has named 27 councils that are operating 84 drinking water supplies that do not comply, and says they have been legally required to have the right barriers in place for nine years.
Among the councils with several supplies which don't meet the standard, are Hurunui, Marlborough, Tasman, Taupo, Waimakariri, Waimate and Waitaki councils.
Meanwhile in Queenstown, roughly 20,000 residents are now able to drink from the taps after the boil water notice was partially lifted this morning.
Tess Brunton is in Queenstown.