“We waste so much [water]… it just flows out to sea”

“We waste so much [water]… it just flows out to sea”

That asinine comment was made by Conor English (Bill’s brother) when he was Chief Executive of Federated Farmers. Leaving aside the fact that this “waste” is an integral part of the freshwater cycle, it does raise the questions of how much water is available and how much is used in new Zealand. Here is a highly condensed factoid to this end.

New Zealand is blessed with 1,100 rivers(1) and 4,000 lakes(2) which are refreshed on average by 600 billion cubic metres(3) of annual precipitation. Of this, 27 billion cubic metres (4.5%) is consumed (taken out and not returned)(4) by human activity. Although this sounds, literally, like a drop in the ocean, the fact is that most of this falls where it is not consumed and conversely most is consumed where it does not fall.

This is the nub of our current freshwater woes.

With current power supply comfortably in excess of demand those major public underground water pipe projects of yore, such as that linking the upper Whakapapa and Moawhango rivers to the Tokaanu power station, have been superceded by the shorter term investment cycles of private projects which appropriate water for sale primarily to pasture irrigators. In contrast to our hydro power schemes this often translates as a lot of demand competing for a little supply.

For example, excluding Manapouri, (16 billion cubes of river water per annum discharged to the sea) Canterbury’s conversion of dry tussock plains into dairy pasture uses nearly half (5 billion cubes) of all NZ’s consumptive water, despite the region accounting for only 10% of the countries natural water supply(4). The Central Plains Water Scheme, a private company part-funded by tax payers care of the Crown Irrigation Fund, is going ahead diverting 25 cumecs (cubic metres, or 1,000 litres, per second) of the Waimakariri and 40 cumecs from the Rakaia and distributing this via 17km of canal and 100km of pipes to 20,000 hectares of dairy farms on the Canterbury Plains(5).

In total Canterbury, Southland and Otago regions account for 86% of the total weekly consumptive allocation in New Zealand during times of maximum take. While most of the allocated water in Southland is for hydro generation, the main water use in Canterbury and Otago is for pasture irrigation. Indeed, nationally 46% of all consumed water is for irrigation of pasture and, to a lesser extent, crops(4). This is the consequence of a global thirst for dairy products, particularly China’s, which buys about a quarter of all our dairy output. Globally we provide 12% of the world market for dairy, or 66% if we exclude Europe(6).

So, whilst we rank third out of 27 OECD countries for how much available freshwater we abstract we come second only to the USA in the same league when it comes to how much water we consume per capita, principally because we have more pasture loving dairy cows than people(4).

Of course the volume-at-any-cost philosophy currently driving our dairy industry comes at an environmental cost and is not too concerned with efficiencies given the seemingly infinite resource-based belief of local planners and decision makers. The environmental costs are seen in numerous reports, the highlights of which are covered in subsequent paragraphs, but the inefficiencies of the sector are less understood, for instance:

Virtually all cows’ milk is dehydrated into milk powder and then re-constituted with fresh water at its point of sale or use. This even includes domestic milk sold in dairies next door to dairy farms! So, for every litre of milk collected, one litre of water is driven off and a subsequent additional litre of water used to reconstitute the dried milk powder.

The driven off water, called condensate, contains impurities such as milk solids and is discharged onto land or rivers such as the Mangatainoka in the Wairarapa, depleting oxygen availability in the water and increasing anaerobic bacterial activity in the soil.

On a global average every litre of milk requires 1020 litres of water. For Waikato, about 945 litres of water are required to produce 1 litre of milk. For Canterbury, it’s 1084 litres of water(7).

In terms of greenhouse gases agriculture generates nearly half – more than all the petrol, diesel and jet fuel vehicles in NZ combined(8).

Back in the world of water, in January 2010, 75% of the total national water allocation consents were for irrigation(4) and over a quarter of our monitored rivers showed an increase in nitrate concentrations primarily as a result of animal waste – principally from the national herd of 6.2 million dairy cows. More rivers showed a decline than improvement in numbers of bugs (the Macroinverterbrate Community Index), another indicator of declining water quality (9).

Thus, there is a clear and undisputed link between the major cause of deterioration of our rivers and unchecked dairy intensification.

Our groundwater fares no better either, with increasing levels of nitrates found in areas where dairy intensification is rife. Those, such as the Manawatu and Waikato rivers, have levels of nitrates which breach NZ health standards for drinking water as nitrates are associated with “blue baby syndrome”(10). Nitrates are the result of either the mineralisation (conversion of organic ammoniacal compounds into inorganic salts in the form of nitrites and nitrates by naturally occurring bacteria) of animal waste, such as urea, or application of excess fertilisers.

And over 60% of monitored freshwater sites are unsuitable for swimming due to risk of infection from e. coli – a bacterium indicating the presence of faecal matter, mainly cow manure, in the water(11).

Latest estimates suggest that only 65% of the maximum consented volume in New Zealand is actually used(12) and thus there is potential to transfer unallocated water from the land asset value to the ecological balance sheet. But, many consenting authorities continue to issue water takes without knowing how much is available, in some cases allocating more water than actually exists!

The dairy industry is facing up to the challenge, but their oft preached credo of cattle bridges over rivers and riparian planting are too little too late. For example:

The Stroud Water Research Center (USA) have recently published a report on riparian planting strips to establish their optimum width concluding that in order to have any effect, on average, they need to be 30 metres wide(13), typically farm planting alongside a stream here in NZ is usually 2 metres at best.

Fonterra’s Sustainable Dairying: Water Accord (SDWA) excludes all streams less than a metre wide and 300mm deep. This effectively excludes many spawning streams for salmonids.

The current high stocking rates (up to 4 cows/hectare), short grazing cycles (30 day rest), intense nutrient load (up to ten urea applications per annum) and effluent production (one cow produces the equivalent faecal matter of 15 humans(14) of the modern dairy farm make all the bridges, culverts, tree plantings and fencing irrelevant – the equivalent of a Band-Aid on a broken back.

Dairy is the main, but not sole, polluter, the other two major contributors are urban sewage and forestry. Many urban sewage treatment plants still discharge raw or only partially treated sewage into rivers such as the Manawatu and at the estuary of the Motueka. Given the slow but steady increase in urban populations and corresponding decrease in rural centres (about 2% each from 1991 to 2006)(15) this problem is unlikely to get better without large scale investment by central Government.

Last, but not least, in the freshwater threats is the insensitive land use practices of forestry, in particular clear-felling. For instance, in late March 2014 a large area of pines was clear felled alongside the lower Wangapeka river, a major tributary of the Motueka and internationally renowned fishery in its own right in Tasman District. Soon after the clear-felling a heavy rainstorm hit the area resulting in huge amounts of prunings, discarded timber and soil washing into the river. Despite the obvious environmental damage caused by the event, there was technically no breach of resource consent conditions in the eyes of the local Council and hence such pollution and destruction of a valuable freshwater fishery was effectively condoned. There is some research into alternatives, such as strip and contour based felling practices as espoused in Europe but insufficient incentives currently to motivate the volume based forestry industry to change their practices.

Forestry is growing: In 1974 there were around 600,000 hectares of exotic productive forestry – in 2014 we have around 1.8 million hectares of forestry (7% of the land mass) of which 90% is one species – Pinus Radiata, or the Monterey Pine(16).

The MPI Sustainable Farming Fund (SFF) has invested $122.8 million on 906 SFF projects across 14 fiscal years (2000−01 to 2013−14). For every $1 spent by the MPI the project partner has contributed $1.27 direct or in kind (17).

References

(1) Wikipedia List of NZ Rivers.
(2) Ministry for the Environment, State of the Environment, Snapshot of Lake .Water Quality in New Zealand, Nov 2006.
(3) Statistics NZ: Water Physical Stock Account: 1995–2010.
(4) MfE Freshwater Demand Allocation 2010.
(5) Central Plains Water Limited Scheme Design (www.cpwl.co.nz).
(6) Statistics NZ, October 2013 Dairy Exports Report.
(7) Sciblogs.co.nz/waiology.
(8) MfE Greenhouse Gas Inventory 2010 Snapshot.
(9) MfE Environmental Reporting, River Condition Indicator update July 2013; INFO 689.
(10) MfE National groundwater quality indicators update: state and trends 1995-2008.
(11) MfE Recreational water quality in New Zealand Indicator update October 2012; INFO 653.
(12) Aqualinc Research, 2010 for MfE.
(13) Stroud Center.org.
(14) www.safe.org.nz.
(15) Statistics NZ, Urban and Rural Migration.
(16) Forest Owners Association, Facts and Figures 2012/2013
(17) Evaluation of the Sustainable Farming Fund Summary Report, 31 January 2014, Ministry for Primary Industries, Kinnect Group.