A farmers' group has added its voice to those trying to stop the Whangarei District Council from dumping untreated sewage into Whangarei Harbour during emergencies.
The council has applied to the Northland Regional Council to renew its resource consent to discharge up to 24,000 cu m a day.
The council says the cost of fixing the infrastructure is $5 million to $21 million, and it would use its consent only during emergencies, usually brought on by deluges.
Five Whangarei Harbour hapu - Ngati Kahu o Torongare, Te Parawhau, Waiariki, Ngati Korora and Nga Uri O Pohe - last week announced their opposition, and they have been joined by Farmers of New Zealand.
"Northland Regional Council requires dairy farmers to provide for stormwater diversion and sufficient storage to ensure there are no discharges during wet periods," operations director Bill Guest said.
"We are of the opinion that rules relating to management of waste or effluent must be consistent across sectors."
Mr Guest said any claims that the district council did not have the money to pay for a necessary infrastructure upgrade were unacceptable. "We believe [the council] needs to address its core business by prioritising its revenue towards the provision of adequate sewage-treatment infrastructure."
The council's infrastructure manager, Simon Weston, said the only way to end the spills would be a huge investment.
This would require a change in priorities or extra charges on ratepayers, he told the Northern Advocate.
Mr Weston said those wanting to end the discharges should think about making submissions to the council's 10-year plan, which comes up for consultation next year.
He said only 15 people turned up to a meeting the council called last year to get feedback before it spent millions on fixing overflows from two pumping stations.
The Advocate said the discharge consent was for the equivalent of 10 Olympic-sized swimming pools.
Public submissions on the consent application close with the Northland Regional Council today.
