Businesses near the Mangati Stream in Bell Block have been told to clean up their act after several unauthorised incidents affected the health of the stream.
In the past the quality of water has suffered because industrial sites have dumped stormwater and wastewater into the stream.
The Taranaki Regional Council now requires consents, from every site in the area, for any discharges thatcould cause contamination.
However, a report shows 42 unauthorised incidents were recorded, 25 relating to consented companies monitored by the council during the 2009 to 2011 period.
Several unauthorised discharges were found but the sources could not be identified.
The large number of discharges into the stormwater system made it difficult to track where the problem was coming from, because there could be 10 to 15 possible causes, Taranaki Regional Council director environment quality Gary Bedford told the consents and regulatory committee yesterday.
More monitoring would not help, he said.
"We have an intense and comprehensive monitoring programme, which picks up incidents when they occur."
Some of the companies were found to be not complying with their consents, and there had been other incidents where the discharges were unauthorised.
In one case, sewage fungus was found in the Mangati Stream below the State Highway 3 bridge, he said.
- Taranaki Daily News
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