Now there's a stink raised over atomisers

A claim the atomiser fence put up around Wanganui's troubled wastewater treatment plant is an unjustified expense has been dismissed by the chairman of Wanganui District Council's infrastructure committee.

Councillor Ray Stevens said the scented odours being sprayed from the atomisers were doing their job and people were commenting on the reduced frequency of smell from the ponds.

"And when they do smell anything, it's also a lot less than it was," Mr Stevens said.

"People remember what it was like in December and January before we installed anything, and it's a huge improvement."

The technology used by the council had been successful around New Zealand and in other parts of the world, he said.

His comments come after council colleague Rob Vinsen questioned the usefulness and cost of the atomisers.

When Mr Vinsen was at the Wanganui Airport a few days ago, the stink had been "putrid" but when he'd parked at the treatment plant gates a few hundred metres away, there was a distinct smell of the "tutti frutti" odour from the atomisers.

Mr Vinsen said if the scent was not noticeable in the central business district, he saw no point in continuing to spend money on the odour fence.

Mr Stevens said the odour fence was costing $3000 a day to run and was part of the process agreed with the Environment Court after the council had been found in breach of its resource consents covering the treatment plant. "The dosing is reviewed early every morning and during the day and the dilution rate is varied, dependent on the waste we are receiving at the time," he said, adding the cost varied between $1000 and $5000 a day.

He said the scent had been detected a considerable distance from the ponds, including at the Avenue, St John's Hill and Aramoho.

"The atomiser fence is useful; it is working and reducing the effect of odour on the public."

Meanwhile, infrastructure manager Mark Hughes told the Chronicle random sampling continued to be carried out at all seven wet industry sites in Castlecliff.

As well as those "grab" samples, each site had undergone two weeks of continuous 24-hour auto-sampling.

These go to a laboratory in Lower Hutt and results should be available in a few weeks.

The council is working on a new bylaw covering trade waste discharges into the treatment system and officers are looking at bylaws and charges that other local authorities have in place.