Fencing Off Rivers For What?

As an example of corporate posturing by big dairy to take the heat off, fencing rivers has been a stunning success. The only trouble is, it has done nothing for the rivers and has contributed to the loss of rivers for the public.

Raising concerns about dairy run-off

By Bill Benfield

Just one of the culprits

This could well be one that New Zealand Fish & Game brought upon itself and its license holders. It was around 17 or 18 years ago that they started raising concerns about dairy run-off into rivers.

I don’t think there is any doubt that the concern was proper, but it failed to look at other things that were happening in the environment and were also ending up in rivers or how the issue could best be addressed.

When the heat came on, Fonterra, the biggest player, moved quickly. To deflect attention by proposing the Dairy and Clean Streams Accord of 2003. It was signed by the Dairy industry, the Ministry of the Environment, local government and the now the Ministry of Primary Industries.

Avoiding the real problems

Taken in?

It is a text book example of a Clayton’s solution – how to maintain and expand intensive agriculture and its serious degradation of rivers while avoiding the real problems.

It involves fencing off river (and lake) margins and banning all animals, even horses from the waterways. As an added public sweetener, the fenced off river margins were to be “planted with natives”.

Not only has it successfully been sold to central and local government, but also to Fish and Game and the Green Party.

In the end, the Fish and Game campaign did nothing to stop the huge expansion of dairy, particularly in Canterbury, but it did achieve, by fencing off rivers, an effective barrier so no animals or anything else much, including Fish and Game licence holders, may ever have

Other river polluters

By focussing on dairy, it has also deflected attention from the other major polluters. A classic case being the 2009 report on the Manawatu by the Cawthron Institute which named that river as being the dirtiest in the world and pointing the finger firmly at dairy, all to the applause of a few academics and misguided people.

Looking at it, there was just no weight of evidence to support such claims, so it was no surprise when three years later in 2012, The Parliamentary Commissioner for the Environment (PCE) issued “The Water Quality in New Zealand Report”. In this she overturned the previous Cawthron findings, that the Manawatu was the most polluted of the Western World.

In fact, the Manawatu River has to put up with partially treated sewerage and, untreated storm water from towns over a huge catchment ranging from Eketahuna to Palmerston North.

 It carries industrial burden from breweries, pharmaceutical works, milk processing plants and freezing works; there is also forestry and council bulldozer operations in the river bed contributing to silting.

There is some intensive dairy, but that is the least of its problems. Yet on the tributaries of the Manawatu, the price is being paid for dirty dairy. The rivers are being fenced off!

The downside of fencing off rivers

Clogged vegetation beside rivers

While fencing off rivers and banning all stock sounds good in principle, the reality is quite different. The river is now separated from the land and normal farming.

It is no longer subject to browse and it quickly becomes overgrown with weeds like blackberry, broom, gorse and even the poisonous tutu. Not only has the river become inaccessible for all normal purposes, but riparian planting does nothing to stop most pollution from entering the waterways.

Also, we have to remember, rivers can cope with the added nutrients of a bit of cow poo, in fact, rivers do better with some nutrients rather than with no nutrients. You’re not going to have much of an ecosystem in distilled water! As well, Mike Joy’s book “Polluted Inheritance” (p34) makes it quite clear that riparian planting does nothing to stop nitrogen from entering the waterways.

The decline of fluvial environments

It is really now that there have been some years of fencing and planting that the outcome is obvious.

 ~ Banks covered in roiling heaps of convolvulus and blackberry, interspersed with broom and some natives are impassable. Access to the rivers is effectively denied. Except at bridges and crossings, it is hard to see any river at all. For all practical purposes, the river is lost.

~ Many of the rivers don’t need that level of protection, so a lot of farmer money is wasted and otherwise useable land sequestered.

~ River habit that was waterfowl nesting and feeding habitat is lost. Recent years have shown a drastic decline in duck numbers, and this must be one of the factors.

~ Since river fencing began, fish numbers have seriously declined. River edges are over run by dense groves of blackberry and convolvulus which hold sediment and stifle aquatic life.

~ Overgrown river banks are an ideal home for Norway (water) rats and other predators.

~ When the river becomes choked with growth and debris, floodwaters will back up across the farm. At that stage, the regional council will move in and dragline the river out, or, if in a larger bed, use bulldozers to rip and cross-blade the bed. The river is now gone, it is now just a flood channel.

~ Un-browsed river margins with long rank grass, natives, blackberry, gorse and other growth blocks light from reaching lower-growing ground-cover plants, and so reducing the natural bio-diversity. Remember, long grasses are not for admiring, in the natural world, they are food to be browsed!

Better management of rivers

How can we manage this side of our rivers, their margins better? It is certainly possible, it just requires a more focused system of river management rather than the current one rule of fencing fits all.

There is certainly case that where there is no intensive dairy, river banks should be left as in near as natural unfenced condition as possible.

Thereafter, the issue is stock. Stock, like sheep, goats and horses are not too much of a problem. Their impact on banks is not great and well within what the life of the river, with its cycles of high and low flows can cope with. Cattle can be a different issue; it is an issue of density and a matter of finding a reasonable level at which agriculture can co-exist with the river.

Where cattle densities are high and stock receive supplementary feed from offsite, i.e. more is being discharged on the land than can be produced from it, they should be excluded from the river.

If mixed stock are grazed, i.e. sheep and cattle, then the “selecta-fence” can be the answer – two top wires to stop cattle and no bottom wires and so sheep are let through. (See the illustration alongside.)

As an example of corporate posturing by big dairy to take the heat off, fencing rivers has been a stunning success. The only trouble is, it has done nothing for the rivers and has contribute to the loss of rivers for the public.

New Zealand’s high-intensity agriculture and misuse of nature is in effect an extractive industry that is mining the environment. As in all mining, there will come a point when the mother lode has been exhausted and the economy will collapse.

Those signs are already there on the Canterbury Plains, and yet there are still plans for further increases by way of extensions to the upper plains scheme for further irrigation and dairy.

Sooner or later, we as a nation will have to diversify away from intensive agriculture or live with the consequences.