Waikare Oyster Farmers’ Waste Minimisation Scheme

What are the objectives of the scheme?

  1. To recover and divert from landfill (recycle) an estimated 270m3 of oyster farm timber waste;
  2. To recover and divert from landfill (recycle) up to 25,000m3 of waste shell from oyster farms over three years for use in cement, lime, and other potential products.
  3. To investigate and if viable, look to establish a sustainable commercial operation that will operate to remove shell from the Waikare Inlet and other oyster farm sites after any Waste Minimisation Fund allocation has been expended. Investigations include:
    • - the ongoing sale of oyster ‘waste’ product (i.e. shell); and
      - the development of a permanent aquaculture land base/headquarters possibility allowing for processing, retail, education and research.
  4. To promote and raise the profile of this innovative waste minimisation project.

Why is this happening?

Due to water contamination, the Waikare oyster farmers were forced to close down operations in August 2001. It was not until 2009, when water quality issues had been resolved, that the majority of the farms were re-opened to allow trading.

During the closure many farms were unable to be maintained. The oysters continued to grow and re-produce, which meant shell waste built up, the racks got heavier, the timber gradually rotted and eventually many collapsed.  When the farms were re-opened in 2009 the majority were in such a spoiled state they were unable to recommence farming.

Farmers were faced with the need to clean up an estimated 25,000m3 of mud and shell build up and remove waste timber before oyster farming could recommence. It should be noted that a number of farms are now semi-operational.

Who is involved?

funding diagram

‘Project Oyster Shell’ is a joint initiative between central and local government agencies, Northland Inc (the regional economic development agency, who are the facilitators), the Waikare Inlet oyster farmers and other industry groups.

As a consequence Waikare Oyster Waste Recovery Ltd has been set up specifically by the Waikare oyster farmers, for the life of the project, and is the primary contractor for implementing Project Oyster Shell.

What is the cost?

This is a three year project (to be completed by October 2014) and is valued at $4m. The Ministry for the Environment, under its Waste Minimisation Fund, has committed $2.1m. The balance of funding will come from other sources, including investment from the Waikare Inlet oyster farmers.

How will it be done?

A trial is being undertaken in November and December 2012 to test various methods for the shell removal. This includes utilising a large barge and digger, a suction pump on a barge and a work team with hand-held equipment to work on farms that are operational. Once the trial is completed the most effective and efficient method/s will be chosen and all farms will be cleaned by that/those method/s. 

Farmers are already removing timber (waste timber needs to be removed before the shell removal).  Shells will be cleaned and then removed, from all farms except one, and taken to a land storage area.  A 20m x 20m reclamation has been built to allow the clean waste shells to be barged from the farms and off-loaded before being stored and/or processed.

How many farms are involved?

There are 24 farms in the Waikare Inlet, covering ~35 hectares.  Of this 22 farms are likely to have worked completed on them.

What are the markets for the waste?

Research is currently being undertaken to look at potential markets for the waste shell.  The Department of Conservation is taking any usable timber for fencing-off wetlands in Kauri Trounson Park.

It is known that oyster shell makes excellent grit for chickens and due to its high component of calcium and lime there are other opportunities, such as using it in cement.

What are the benefits of the scheme?

Project Oyster Shell will return the farms to their natural state. Farmers can then rebuild.  Recommencement of operations will support the overall expansion of the industry in Northland, with the enterprise potentially providing significant economic benefits to the Northland economy. On-going shell recycling could become a standard part of the farming operations which will increase the economic and environmental benefits and, if applied more widely, could result in oyster farming working towards a zero waste industry.

What are the long term goals?

  1. To rebuild a thriving oyster industry in the Waikare Inlet previously worth $7m per annum with the opportunity to grow it on to a $30m+ industry;
  2. To have the Waikare Inlet recognised as an ‘organic’ farming area;
  3. To create sustainable markets for both the oyster meat and shell - using science to develop ‘added value’ products recycling oyster shells for use in construction industry and medical sector research
  4. To establish a zero waste industry in Northland e.g. the Department of Conservation is to use recovered spent timber for fencing-off wetlands;
  5. To develop an aquaculture centre, which may include retail, processing, educational and research facilities as well as other aquaculture products to oysters;
  6. To build a new barge dock and processing plant in Opua, Bay of Islands;
  7. To create more jobs – estimated at in excess of 200+; and
  8. To contributing to a goal of $300m annual aquaculture turnover here in Northland.

Check out updates at www.waikareoysterproject.co.nz

To correspond with those involved with the scheme contact Wayne Hutchinson.