New research into the country's freshwater use has found that many foods and drinks require more than 100 litres of water to produce.
Massey University and Plant and Food Research scientists are measuring water footprints - the total amount of water used in the production process of goods and servces.
A senior lecturer in environmental hydrology and soil science at Massey University, Ranvir Singh, says their research has found that it takes an estimated 109 litres of water to produce a glass of wine.
He says this is water that is used for growing, procuring raw ingredients and processing, as well as for storage, transport, retail and by the consumer.
Dr Singh says other water footprints calculated to date include that of a glass of milk, which requires 211 litres of water to produce, and a bag of potato crisps, which takes 157 litres.
He says it's important that New Zealanders know how much water is used in each production process.
