Local Govt | National News Video | Parliament Headlines | Politics Headlines | Search


Desludging Of Taumarunui Wastewater Treatment Plant To Use Bio-bags

Preparation for desludging of the Taumarunui (Hikumutu) Wastewater Treatment Plant is well underway with work on a lined pit for holding three large bio-bags to contain the settling pond sludge almost complete.

Acting Environmental Manager Stuart Watson said that the desludging is part of the scheduled maintenance of the settling ponds required to keep the bugs in the ponds working efficiently and producing water clean enough to release into the environment.

“The settling ponds were last desludged around eight years ago with the sludge spread directly onto surrounding fields however new National Environmental Standards for Freshwater means that this method is no longer appropriate,” he said.

“The process this time involves dredging the sludge and pumping it into three custom built bio-bags each around 13m wide by 30m long held in the purpose built pit above the settling ponds.

As desludging of the settling ponds is an on-going maintenance requirement the bio-bag pit has been made as large as possible to future proof it for future desludging for years to come.

Once the construction of the holding pit is complete the bio-bags will be installed prior to the filling process which will take around a week per bag.

A special polymer agent that acts as a coagulant is mixed with the sludge so that when it is pumped into the bio-bags the solids settle and form into larger clusters.

The polymer binds the solids together locking up any potential hazards including odour within the bio-bag.

From there the sludge is left to dry out and breakdown within the bio-bags. Water seeping out of the bio-bags as the sludge dries comes out crystal clear but is piped back to the settling ponds for treatment.

The breakdown of the sludge can take between two to five years when it can then be utilised as a high quality soil. As the sludge breaks down it consolidates allowing more sludge to be added to the existing bags.

An alternative to leaving the bio-bags to dry out is to plant directly into the top of them and let the plants use up the nutrients and reduce the sludge volume as they grow.”

Mr Watson added that while our specialist contractor Hydra-Care states local residents will not be impacted by offensive odours or other hazards we will be improving the look of the site by installing fencing and plantings.

“Hydra-Care have undertaken desludging work for numerous councils all around NZ and I would encourage anyone interested in their work to look at their website hydracare.co.nz

© Scoop Media

Parliament Headlines | Politics Headlines | Regional Headlines

Gordon Campbell: On Northland’s Covid Case, And Biden’s Battle Lines

The South African variant at the centre of the Northland case of community transmission calls for a reset of several aspects of our Covid response. Some aspects of that reset are overdue. Since the pandemic began, the debate on whether transmission can be (or is mainly) via small aerosols rather than larger droplets has barely been reflected in official health policy, which has focussed largely on the droplets...More>>


Ministry Of Health: Probable Case Of COVID-19 In A Returnee

The Ministry of Health is investigating a positive test result in a person who recently travelled from overseas and completed their stay in managed isolation in a facility in Auckland. In the case we are investigating and reporting today, the person had ... More>>


Oranga Tamariki: Chief Executive Grainne Moss Steps Down

Controversial Oranga Tamariki chief executive Grainne Moss has decided to step down. More>>


USA: Prime Minister Congratulates President Joe Biden On His Inauguration

Prime Minister Jacinda Ardern has congratulated President Joe Biden on his inauguration as the 46th President of the United States of America. “I look forward to building a close relationship with President Biden and working with him on issues that matter ... More>>


New Zealand Government: Cook Islanders To Resume Travel To New Zealand

The Prime Minister of New Zealand Jacinda Ardern and the Prime Minister of the Cook Islands Mark Brown have announced passengers from the Cook Islands can resume quarantine-free travel into New Zealand from 21 January, enabling access to essential services such ... More>>


Oxfam NZ: Wealth Of New Zealand’s Richest Person’s Soars By $3.4bn Since Beginning Of Pandemic

New Zealand’s richest citizen, Graeme Hart, has seen his fortune increase by NZ$3,494,333,333 since March 2020 – a sum equivalent to over half a million New Zealanders receiving a cheque for NZ$6,849 each, reveals a new analysis from Oxfam today. The New Zealand ... More>>


Government: New Public Housing Plan Announced

RT HON JACINDA ARDERN HON DR MEGAN WOODS The Government has released its Public Housing Plan 2021-2024 which outlines the intention of where 8,000 additional public and transitional housing places announced in Budget 2020, will go. “The Government ... More>>

Government: Pre-Departure Testing Extended To All Passengers To New Zealand

To further protect New Zealand from COVID-19, the Government is extending pre-departure testing to all passengers to New Zealand except from Australia, Antarctica and most Pacific Islands, COVID-19 Response Minister Chris Hipkins said today. More>>





InfoPages News Channels