Some businesses in Whanganui say they're losing customers because of the foul smell emanating from the town's wastewater plant.
There have been problems with the plant since before Christmas and most recently sewage and untreated waste water was pumped into the ocean for two days.
Tourism operators say the strong odour from the plant is discouraging people from visiting the city and that's affecting their profits.
Clive Rivers owns a bed and breakfast and youth hostel whose business he said had dropped off by up to 20% because of the stench.
"We usually have people staying on for more than a day and they're all going at least after 24 hours."
Mr Rivers said his comments book is full of complaints and blogs by travellers are calling the smell appalling and urging people to avoid "Ponganui".
The untreated waste water was diverted into the ocean from Friday morning after high levels of hydrogen sulphide from an industrial company affected the Beach Road pumping station. That made the smell, which has plagued the city for months, worse.
Mayor Annette Main said the council stopped diverting the waste just after 9am on Sunday.
She does not know how much was pumped into the sea in the two days but said it was mostly stormwater.