Waikato one of cleanest rivers in the world: Professor

Professor Jacqueline Rowarth. Photo / file.

The Waikato River is one of the five cleanest rivers in the world, according to a leading Waikato University scientist.

Jacqueline Rowarth, Professor of agribusiness at the university, told a gathering of more than 180 farmers and land owners at Pukekohe on October 3, that in the past 70 years increased fertility and humus on farm land had allowed grasses to provide good root structure and thus better soil stability in hill country. This had steadily reduced the run-off of soil and other nutrients into waterways, and gradually river water quality across the nation was improving. The Waikato, Clutha and Waitaki Rivers were classic examples of this improvement, and all three were now rated among the top five cleanest rivers in the world.

People from as far away as Taupo and Coromandel attended the presentation. They were all concerned at the impact of the Waikato Regional Council's Healthy River Plan Change 1 (PC1) on land owners and users throughout the council's area.

The plan change proposal, aimed at restoring and protecting the Waikato and Waipa rivers, was approved last month by Waikato Regional Council for public notification. Councillors were split 7-7 on a motion to approve and the measure was passed on the casting vote of the chairperson Paula Southgate.

The meeting was organised by the Primary Land Users Group (PLUG), who had asked Professor Rowarth for her opinion on the state of the rivers running through the Waikato.

The group, representing a cross-section of forestry, dairy, horticulture and dry-stock land-users, has misgivings over what they believe will be "significant negative impacts" that PC1 will have on both the primary sector industries and on rural communities generally throughout the Waikato.

Professor Rowarth told the meeting that the concept of PC1, as presented by the Waikato Regional Council, was founded on modelling which had unreliable outcomes, and that the regulations imposed in the Plan Change did not have a robust scientific basis. She said the social and economic outcomes of the resulting regulations for affected rural communities were considerable.

She said that through available scientific reporting, the outcomes which PC1 sought could be achieved through good land management practices. This, she said, was an approach which was more likely to foster innovation, succession and progression within farming and rural communities without damaging or possibly destroying the livelihoods of hard-working farming families and their rural communities.

She told the meeting that her investigations into international waterways had shown that they carried considerably higher levels of nitrogen than those in New Zealand, yet those levels were not causing human deaths. She concluded that New Zealand waterways' nitrogen levels were "well below acceptable standards".

She also expressed concern at the social impact the PC1 change would have in rural areas, saying that more than 5000 jobs throughout the wider Waikato region were predicted to be lost if the scheme was implemented.

Commenting on the meeting, Bruce Cameron, a Glen Murray dry-stock farmer and an executive member of PLUG, said that to know the Waikato River was one of the world's cleanest rivers "should be shouted from the rooftops, and New Zealanders should be very proud of how well they are being looked after".

"It goes to show that the work done by farmers over the years is reflected by the upward trend in improving water quality," he said. "One wonders why the Waikato Regional Council PC1 has come down so hard on farmers across the catchments of the Waikato and Waipa Rivers.

"On the easy country it may be simple to fence off rivers and streams, but this is not so in the hill country. There, for very little gain, the huge costs of fencing cannot be justified."