Whanganui Chronicle
  • Whanganui Chronicle home
  • Latest news
  • Sport
  • Business
  • Opinion
  • Lifestyle
  • Property
  • Death notices
  • Classifieds

Subscriptions

  • Herald Premium
  • Viva Premium
  • The Listener
  • BusinessDesk

Sections

  • Latest news
  • On The Up
  • Sport
  • Business
  • Opinion
  • Lifestyle
  • Property
    • All Property
    • Residential property listings
  • Rural
    • All Rural
    • Dairy farming
    • Sheep & beef farming
    • Horticulture
    • Animal health
    • Rural business
    • Rural life
    • Rural technology

Locations

  • Taranaki
  • National Park
  • Whakapapa
  • Ohakune
  • Raetihi
  • Taihape
  • Marton
  • Feilding
  • Palmerston North

Media

  • Video
  • Photo galleries
  • Today's Paper - E-Editions
  • Photo sales
  • Classifieds

Weather

  • New Plymouth
  • Whanganui
  • Palmertson North
  • Levin

NZME Network

  • Advertise with NZME
  • OneRoof
  • Driven Car Guide
  • BusinessDesk
  • Newstalk ZB
  • Sunlive
  • ZM
  • The Hits
  • Coast
  • Radio Hauraki
  • The Alternative Commentary Collective
  • Gold
  • Flava
  • iHeart Radio
  • Hokonui
  • Radio Wanaka
  • iHeartCountry New Zealand
  • Restaurant Hub
  • NZME Events

SubscribeSign In
Advertisement
Advertise with NZME.
Home / Whanganui Chronicle

Progress being made on smell

By John Maslin
Whanganui Chronicle·
2 Apr, 2013 05:33 PM3 mins to read

Subscribe to listen

Access to Herald Premium articles require a Premium subscription. Subscribe now to listen.
Already a subscriber?  Sign in here

Listening to articles is free for open-access content—explore other articles or learn more about text-to-speech.
‌
Save

    Share this article

Remedial work at Wanganui's ailing wastewater treatment ponds is gaining some headway, albeit gradual.

In the latest development, a dive team sent into the murky ponds found the sludge layer in the main pond is breaking down.

According to Mark Hughes, Wanganui District Council infrastructure manager, this is the result of dumping tonnes of lime slurry into the ponds, as well as dosing the water with hydrogen peroxide.

Mr Hughes said commercial divers found the sludge had dispersed into the smaller, lower pond where it was forming a dense layer about 2m deep. The sludge layer was creating the hydrogen sulphide gas that has wafted over the city since December.

Yesterday, he said the bad odours coming from the ponds were still occurring and would for some time yet, but they were happening less frequently.

Advertisement
Advertise with NZME.
Advertisement
Advertise with NZME.

He said the movement of sludge from the large pond to the smaller one did not pose any immediate problem for the treatment system.

"This is a positive sign and will make it easier for any longer-term remedial or modification work to be done on the main pond," he said.

He said the strong smell of hydrogen sulphide had gone and that indicated treatment efforts to stop that gas bubbling up from the sludge layer had worked. However, the smell coming from the ponds now was that of raw sewage, so there was still work to be done.

Advertisement
Advertise with NZME.

Mr Hughes said the sludge layer in the main pond has been replaced with a less dense, suspended, solid-type flock, which was about 4m deep.

He said Cardno BTO wastewater treatment consultants said the improvement was mostly because of the improved hydraulics of the new aerators working in the top pond.

There are 14 aerators of various sizes working in the top pond, aimed at intensifying oxygen levels to assist the treatment process, but he could not say how many aerators would eventually be used in the plant.

"These aerators are more effective than the original ones.

"They're a different design and with improved hydraulics."

Mr Hughes said another new aerator went into operation about a week before Easter, one designed and built by council staff "and it's working well".

"We've been working on modifying another aerator and new turbo jet aerators will begin arriving at the end of this week," he said.

"We are now starting to see a gradual increase in dissolved oxygen in the main pond." He said the bio-augmentation programme that ran for some weeks has stopped, but applications of lime slurry and doses of hydrogen peroxide continued, all aimed at lifting oxygen levels.

A new high pressure atomiser system will be installed soon, with pipes being laid this week.

"The higher pressure means a finer mist will be sprayed over the treatment plant to help neutralise the odour.

Advertisement
Advertise with NZME.

"This mist will also disperse in the atmosphere more quickly and provide more coverage than the previous low-pressure system," Mr Hughes said.

Save

    Share this article

Latest from Whanganui Chronicle

Whanganui Chronicle

'Easy option': Airport users unhappy with proposal to shut runways

13 Jul 06:00 PM
Whanganui Chronicle

'What residents deserve': Water trial treatment plant to be set up in Marton

13 Jul 05:15 PM
Whanganui Chronicle

‘A win-win’: Forestry company gifts venison to food bank

13 Jul 05:00 PM

From early mornings to easy living

sponsored
Advertisement
Advertise with NZME.

Latest from Whanganui Chronicle

'Easy option': Airport users unhappy with proposal to shut runways

'Easy option': Airport users unhappy with proposal to shut runways

13 Jul 06:00 PM

'Basically, on a windy day, there won’t be any training.'

'What residents deserve': Water trial treatment plant to be set up in Marton

'What residents deserve': Water trial treatment plant to be set up in Marton

13 Jul 05:15 PM
‘A win-win’: Forestry company gifts venison to food bank

‘A win-win’: Forestry company gifts venison to food bank

13 Jul 05:00 PM
RSA 'alive and well' despite premises closure

RSA 'alive and well' despite premises closure

11 Jul 06:00 PM
Solar bat monitors uncover secrets of Auckland’s night sky
sponsored

Solar bat monitors uncover secrets of Auckland’s night sky

NZ Herald
  • About NZ Herald
  • Meet the journalists
  • Newsletters
  • Classifieds
  • Help & support
  • Contact us
  • House rules
  • Privacy Policy
  • Terms of use
  • Competition terms & conditions
  • Our use of AI
Subscriber Services
  • Whanganui Chronicle e-edition
  • Manage your print subscription
  • Manage your digital subscription
  • Subscribe to Herald Premium
  • Subscribe to the Whanganui Chronicle
  • Gift a subscription
  • Subscriber FAQs
  • Subscription terms & conditions
  • Promotions and subscriber benefits
NZME Network
  • Whanganui Chronicle
  • The New Zealand Herald
  • The Northland Age
  • The Northern Advocate
  • Waikato Herald
  • Bay of Plenty Times
  • Rotorua Daily Post
  • Hawke's Bay Today
  • Viva
  • NZ Listener
  • Newstalk ZB
  • BusinessDesk
  • OneRoof
  • Driven Car Guide
  • iHeart Radio
  • Restaurant Hub
NZME
  • NZME Events
  • About NZME
  • NZME careers
  • Advertise with NZME
  • Digital self-service advertising
  • Book your classified ad
  • Photo sales
  • © Copyright 2025 NZME Publishing Limited
TOP