Mangatainoka River – April 3, 2011

The Mangatainoka River has been made famous by Tui with their beer ads – scantily dressed women supposedly frolicking in the river near the brewery. Well, it’s true that the Mangatainoka is near the brewery, but it is heavily polluted so I don’t reckon they frolicked in the river itself.

As recently as January 18, the regional council warned people to keep their dogs out of the river, otherwise they could eat the toxic slimy black sludge algal bloom and die.

Getting vomiting and diarrhoea in a bikini might look glamorous but it’s still vomiting and diarrhoea.

The Mangatainoka has its headwaters in the eastern slopes of the Tararua Ranges Forest park where the water is clean and full of life. But as it travels east onto the farmland of the Wairarapa it collects pollution from agriculture, sewerage and industry.

The degraded river then turns northward to join the Manawatu for the journey through the gorge that cuts a mountain range in two, creating the Tararuas to the south and the Ruahines to the north, before flowing through Palmerston North and out to sea on the west coast.

Old man Manawatu is older than the mountains themselves but his sickness is palpable.

We started just downstream from the Pahiatua bridge, not far from the Fonterra processing plant.

There were some of the crew from the Ruamahanga trip, including Mike Birch from Whitewater NZ and Dave Woodcock from Wairapapa Outdoor, Vicky and Heike from Massey Uni ecological economics who have been working with the community on solutions, and others who just cared about the state of the river including the Wai Not Go Green crew. Special mention to Stella McQueen who has self-published a book on looking after native fish in an aquarium and is now doing a masters in freshwater ecology at Massey – awesome.

The Greens have been battling with Fonterra because of their application to get a 22 year extension for their resource consent to dump untreated condensate from their Pahiatua plant (below) straight into the Mangatainoka.

The condensate is what comes off the milk when it’s boiled to create milk powder – it has elevated levels of nutrients and is hot.

I had gone to look at the discharge point for the Fonterra plant in October last year. Steaming milky smelling fluid, visible through an open manhole cover, could be seen pouring into the Brechnin stream which then drained into the Mangatainoka.

There were huge algal blooms in the stream.

Fonterra say that by changing the discharge point, from the Brechnin Stream to the Mangatainoka itself, they will improve the stream, which is probably true. But they will still dump into the river.

Fonterra argues that the nutrient-rich steaming water will make little difference to the Mangatainoka because it is already so polluted, which is also true to a point, but also quite shocking. Remarkably, in their application they even concede that agricultural runoff is one of the main sources of pollution of the Mangtainoka. But they argue that because of the existing pollution they should be allowed to keep polluting the river.

That which makes this grass green will also make the river green

It is deeply hypocritical that Fonterra downplays agricultural pollution when we try to get them to clean up dairy farms, but then they play up agricultural pollution when applying for a point source discharge for their processing plant.

In Victoria, Australia, where Fonterra pay for their water and there are stronger regulations, Fonterra have invested in reverse osmosis technology which turns condensate into clean water that can be reused in the processing plant. In NZ the water is free and there are few regulations so they figure ‘why spend the money to clean and reuse the water when you can get more bore water for free and dump the polluted water in the nearest river’? Of course this goes completely against the Manawatu Accord that they signed last year in which they promised to be part of the solution for cleaning up the river – if everyone took the approach that it’s already polluted so a bit more pollution won’t matter then the river will only ever get dirtier.

The flow in the river was pretty low so we had to carry the rafts over many of the little rapids. The river bottom was covered in sediment and algal growth. There were very few fish visible. I lifted up the rocks in the riffles to find invertebrates but there were precious few. Fish and Game’s drift dive results have shown a dramatic drop in the number of trout in the river from about 96 trout per km in 1987 to 7 trout per km in 2009.

Fonterra are right that agricultural pollution has left the river in a dreadful state. We also drifted past the discharge point for the Pahiatua town sewerage; charming.

The river was full of navigation hazards left over from previous pointless flood mitigation attempts – large railway irons poking out of the river bed (like the Ruamahanga), wire mesh and other crap.

Finally we rounded the bend and there was the Tui brewery.

I nearly stripped off and frolicked, but then the large blue plastic pipe discharging god-knows-what put me off.

Thanks to Mike for his organising role, Dave for the rafts, and everyone for coming along.


5 Comments Posted

  1. We’re luckier than most in that New Zealanders care more for the environment than many in other countries. However this does not seem to be helping to protect our natural resources with many River’s not fit to swim in let alone drink from. Labour and National’s ineptness has left a terrible legacy.

  2. By the time Big Business finishes and walks away from our country, all that will be left is a stinking polluted sewer, Joe Public doesnt have a clue and at this point couldnt care less, because Govt represents the people it also cannot care less. Wake Up NZ before its too late!

Comments are closed.