Norrie Day: Mystified at mania for building dams

Norrie Day

I suppose enough has been said in opposition and support over the construction of the Ruataniwha Dam project.

I myself cannot understand this New Zealand urge to build these massive dams. To a point, yes, I reluctantly agree with power generation.

Even with these dams we have ruined some of our wonderful rivers and streams. One only has to look at the South Island's Selwyn River and our own Manawatu River, though this river has no dam, but are classic examples of the scourge of pollution.

So it mystifies me our mania for building dams while the US is dismantling or blowing them up. In the last two years 72 dams have been removed, the last one was the White Clay Creek Dam. Large dam removals, like those just completed on the Elwha River including a 64 metre dam plus a high dam proposed for demolition on the lower Snake River.

In two decades, 865 dams have been dismantled or blown up. Japan and Europe are following the same pattern.

Scientists and environmentalists have criticised the Federal Snake River dams for their devastating effects on the water life. The White Salmon River In Washington State began flowing again in 2011 after nearly 100 years. Condit Dam was disabled when it was blown up.

A lot of the waterways have now returned to normal from the head waters to the delta and the estuary. Salmon and steellheads have returned plus many other species of fish and wildlife.

Reading the history of these dams is the reason why I am a firm anti dam person. To me the Ruataniwha Dam has too many grey areas.

If this dam goes ahead there is no doubt that it will affect and add to the troubles we already have with the Tukituki River. This river is already suffering from pollutants, from the inadequate sewage plants at Waipukarau and Waipawa plus browsing cattle in the river.

Remember that their sewage plants are above the planned dam site and when the sewage plant is open to adverse weather untreated sewage will still flow into the Tukituki River.

Financing this dam? If I was a financier I would be most reluctant to finance any part of the project.

I have read all the articles and letters pertaining to the dam, yet there has not been one mention of one vital flaw in a dams construction and its life span.

This affects ALL dams worldwide, the proven fact that dams emit methane, carbon dioxide and nitrous oxide. The deadly emission of these gases into the atmosphere is partly causing global warming.

Even Ruataniwha will emit certain levels of methane, carbon dioxide, and nitrous oxide. As an example, the world's biggest dam emits 104 million metric tonnes annually of methane. These gases are generated by rotten vegetation and soils due to flooding of reservoirs. The trapping of sediment in reservoirs acts as a carbon generator, also during the dam's lifespan all vegetation that will flow into the reservoir. It's a scientific fact that dams contribute 4 per cent of the earth's global warming.

I believe that water retention on a small scale could be in the hands of those farmers who rely on irrigation, yes maybe with a little assistance from HBRC. It would be a lot cheaper all round than this controversial project.

Norrie Day has a 45-year involvement as a councillor for the HB Acclimatisation Society and HB Fish and Game, as well as 24 years as an honorary wildlife officer. He is a founding member of the HB Federation of Angling Clubs, now the NZ Federation of Freshwater Anglers.
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