Dairy Farms Using Same Amount of Water as 60 Million People

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Dairy Farms Using Same Amount of Water as 60 Million People

Using Dairy NZ numbers, economist Peter Fraser and agricultural consultant Dr Alison Dewes calculate the water consumption of New Zealand dairy farms is equivalent to the residential use of 60 million people.

This is on top of the often quoted figure that New Zealand's dairy herd has the environmental footprint equivalent to 90 million people.

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Image source: phxere

Debate over water use has become a key electoral issue following the Labour Party's proposal to charge irrigators a royalty of up to two cents for every thousand litres (one cubic metre) of water used. This has resulted in considerable confusion as claim and counter-claim are exchanged.

"Let's start with Dairy NZ's own numbers," Mr Fraser said.

Dairy NZ states there are 12,000 dairy herds in New Zealand and collectively they consume 4.8 billion cubic metres of water. Given residential water use in New Zealand is around 80 cubic metres per person per annum, these farms are collectively using water equivalent to 60 million people.

"This seems quite a lot," Mr Fraser remarked.

However, in terms of water use, not all farms are created equal - as 10,000 dairy farms do not irrigate at all. As a result, they account for only three per cent of the 4.8 billion cubic metre number, which implies the 2,000 irrigated dairy farms use the other 97 per cent, which is 4.65 billion cubic metres.

This is equivalent to the residential use of 58.2 million people, which is slightly less than the combined populations of Sydney, London, Los Angeles, Tokyo, Jakarta, Rio, New York and Sao Paulo.

"The bottom-line is Dairy NZ's numbers suggest fewer than 20 per cent of dairy farms are using over 95 per cent of the water - and that hardly looks like a random walk," Mr Fraser said.

"The implication is if a water royalty was imposed on irrigators then over 80 per cent of dairy farmers will be unaffected," Mr Fraser said.

There is a group of 'mega-farms' that are 'mega-users' of water - and their potential water bill will be considerably higher simply because they use considerably more water - and that seems both efficient and equitable.

Dr Dewes says most people do not realise the sheer volume of water being used by irrigated dairy farms, especially if they are sited on leaky, gravelly soils (as is much of Canterbury).

"Each of these farms, on average, uses 1.16 million cubic metres of water. This is equivalent to the residential water use of 14,500 people, which is a little over twice the population of Morrinsville," Dr Dewes explained.

Even these farms face a prospective annual water bill of only $23,300 at two cents per cubic metre - meaning to get to the $50,000 figure a farm either has to be enormous or diversified into wet-rice farming.

Read full article: The Cattle Site

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