The Green Party has been accused of not checking the facts over its claims the Waitara River was one of the country's most polluted.
Green MP Eugenie Sage said the Taranaki Regional Council needed to realise it had a pollution problem and focus on ensuring rivers and streams were safe to swim in.
Waitara's river water quality was among the worst in New Zealand, she said.
Yesterday, council director of environment quality Gary Bedford said discussion about water quality in Taranaki deserved better than "glib generalisations and unfounded allegations".
"It is disappointing that the Green Party and its spokeswoman, Eugenie Sage, did not check the facts before talking to the media about the state of the Waitara River and Taranaki waterways in general," he said.
"The facts are that as is the case for waterways across the region as a whole, the health of the Waitara River is stable, and improving on some measures."
Mr Bedford said the National Institute of Water and Atmospheric Research's water quality measures on clarity, concentrations of ammonia and total phosphorus had remained stable within the Waitara River over the past two decades.
A previous trend of worsening nitrate, nitrogen, and dissolved phosphorus levels in the Waitara River had been arrested, he said.
"The plain truth is that the Waitara River is in far better shape that it was 20 to 30 years ago, when poorly-treated sewage and wastewater from townships and dairy factories was regularly discharged into it.
"A great deal of community investment has gone into the protection and enhancement of the Waitara and other rivers."
Ms Sage, who was taking part in the party's Dirty Water tour, said the council needed to create and implement greater policy around improving river water quality
Mr Bedford said she had not acknowledged the sheer size of the Riparian Management Programme being delivered in Taranaki.
"It is of world scale, and is the biggest voluntary environmental enhancement programme in New Zealand.
"The programme is not only ongoing, but the rate at which waterways are being fenced and planted is increasing exponentially.
"As the council reported to the community late last year, long- term monitoring shows the quality of the region's waterways overall is being maintained, and in some places it is improving significantly."
He said investments included the removal of the Inglewood oxidation ponds discharge, closure of the Waitara and Inglewood landfills and the capturing and diversion of leachate from other landfill sites.
"These initiatives reflect systematic, comprehensive and ongoing efforts by the council and the community aimed at enhancing the Waitara catchment, over the past two decades in particular.
"Critically, the ecological quality of the Waitara River is improving."
- © Fairfax NZ News
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