Wanganui District Council has not breached resource consent despite the city's wastewater treatment plant having to be partially shut down.
The aerators at the plant were shut down over the weekend after a major intake of protein material through the Beach Rd pumping station, from an unknown source.
Residents throughout Wanganui, but especially the Kaitoke-Marybank area, reported a "horrendous" smell coming from the plant, that tainted washing and irritated some people's throats.
Nic Peet, Horizons Regional Council's group manager of strategy and regulation, said a Horizons staff member visited the plant yesterday afternoon following a number of complaints to Horizons' environmental pollution hotline.
"However, at the time of the visit, the odour was not considered to be objectionable and the winds were increasing. As a result, Wanganui District Council was not considered to be in breach of consent conditions at the time of Horizons' inspection."
But Mr Peet said he understood that the odour was stronger at other times of the day and Horizons would request a log of odour complaints received by the Wanganui District Council.
Mr Peet said the aerator was shut down before Horizons visited the plant. He said he was unable to confirm that an industrial site contributed to the smell.
Mr Peet said complaints to Horizons' pollution hotline were investigated by duty staff to verify the nature of the complaint.
Meanwhile, Wanganui District Council's infrastructure manager, Mark Hughes, said the partial shutdown of the plant was likely to continue for the rest of the week. "The aerators, except one small one, remain shut down until the protein compounds can be treated and limited aeration and bioaugmentation recommenced."