Artificial wetlands could play a significant role in cleaning up New Zealand’s waterways, with several pilot programmes underway to test the theory.
It comes as environmental groups call for more work to be done to restore the habitats known as the ‘kidneys of the earth’.
An experiment by the Regional Council, NIWA, Fonterra and the local Tukipo catchment group is currently underway in central Hawke’s Bay.
Corporately, they are constructing a new one and a half hectare wetland on Larry White’s land in Ashley Clinton.
White told 1 NEWS farmers are now having to face the effects of historic practices that are not as sustainable as they thought.
“We have probably taken on practices that were unsustainable…unknowingly at the time.
“We now know that they weren’t and so we’ve got to rectify that,” he says.
Wetland soils contain bacteria which convert nitrogen dissolved in the water, into gas.
“So they are turning one form of nitrogen that’s causing problems into another form of nitrogen which is not causing us trouble,” explains Andy Hicks of Hawke’s Bay Regional Council. (HBRC).
The catchment on White’s farm, contains twice the amount of toxic nitrates than allowed by the Regional Council.
“A wetland of this size should be removing about 25 per cent of the nitrogen load entering it,” says Hicks.
Over $350,000 of funding has been used to make it happen - something the White family say they couldn't do on their own.
Fonterra says it is working in-house and with farmers to reduce its environmental impact.
“Trying to steer away from that coal and we really are making good headway into that - looking at our packaging and transport and shipping all across the co-op,” says Fonterra’s Anna Reddish.
More than 90 per cent of New Zealand's natural wetlands have been destroyed. Forest and Bird wants more Government and industry collaboration to restore them.
“The more wetlands we have the better off we are to fight the effects of climate change,” says Annabeth Cohen of Forest and Bird.
“What we need is a national restoration plan to see wetlands put back across the country,” she says.
The water quality of the wetland on White’s land will be monitored over three years.