Oyster waste to be removed from Waikare Inlet

If everyone has done their sums right, a public/private project to remove thousands of tonnes of waste oyster shells and timber from the Bay of Islands' Waikare Inlet will be like the gift that keeps on giving.

The three-year clean-up project will enable a destroyed industry to be revived; generate revenue by selling ground-up shells for use in industry and mulched wood; create up to 14 jobs; offer research opportunities to senior university students and has potential to be extended to other harbours.

And crucially for the north, for the first time, the clean-up project brought public and private interests together to brainstorm a solution to lift a Northland community out of stalemate.

Northland Regional Council staff raised the issue; Enterprise Northland (a subsidiary of the NRC's Community Trust) drove the project and worked through ways of implementing it with a wide range of stakeholders over the past year. A consortium of oyster farmers has formed a company for the recycling and clean-up work, under contract to Enterprise Northland.

EN chair Andy Britton says the concept provides a template for a co-operative approach to improving the economic health of the region, case by case, in the teeth of "a perfect storm". All regions are in the same boat, facing severe financial constraints brought on by "a perfect storm" of factors which include recession; the Christchurch re-build and costs around setting up the super-city, he says.

"There is not one big solution for our problems but a collective of initiatives that can make a difference," he says.

"Money and investment are important but nothing matches local innovation and local solutions for making a difference."

The Waikare Inlet's multi-million dollar oyster-farming industry in the inlet collapsed in the early 2000's, when the farms were closed due to sewage contamination and an associated outbreak of norovirus infection.

Then the unharvested, oyster-laden frames gradually collapsed, depositing an estimated 6400 tonnes of waste oyster shell and 300 tonnes of waste timber over 30ha of inter-tidal mud.

Upgrades to the wastewater treatment plant in Kawakawa and improvements to the management of on-site and boat sewage gradually improved the water quality to the point where the oyster farms could be safely re-established - but for the mess in the mud and lack of money. The farmers removed some of the debris but none of them had the resources to do a comprehensive clean-up.

Dr Jacquie Reed, EN aquaculture project manager (seconded from the Northland Regional Council), said the council compliance monitoring team had realised that the restoration of the industry was being stymied because none of the farmers had an income.

Teams from several departments including policy and planning monitoring and consents had brainstormed ideas.

"We said to ourselves, what are oyster shells made of? Calcium carbonate? Isn't that what is in cement?"

So the project management team asked Golden Bay Cement to test samples ... and was told these were as good as any of the best limestone used by the company.

Dr Reed says the company has been very supportive in helping the management team research uses for the crushed shells; Whangarei-based companies had indicated they would be willing to buy the washed waste shells for cement or lime production. The Far North District Council had provided advice on possible locations for stockpiling the retrieved shells and timber, and could use the mulch. Enterprise Northland had no money for the project but casting around for funding sources she had been amazed to find the project ticked all the boxes for assistance from the government's Waste Minimisation Fund.

"I thought, this is it! These farmers have had some really big setbacks, this is our chance to help them."

The grant from the fund will be used to meet the cost of EN project management; the Waikare Waste Recovery Company's on-site co-ordinator; waste minimisation labour costs, and specialist recycling equipment and plant. The company is a consortium of oyster-farmers, who will share costs to a pre-determined formula.

Dr Reed says one reason the project was successful getting funding was because so many partners were involved. Minister for the Environment Nick Smith, visiting Waikare to announce the grant, complimented the team because "the risk was shared by central government, local government, business and oyster-farmers."

Dr Reed says the team had worked to ensure every necessary consent, every arrangement had been meticulously researched and put in place to ensure the project had stability and durability. "We also looked at comparative prices for all equipment, asked whether it would be best to lease, borrow or buy. We worked our way through every single one of the issues."

No one person could be picked out to take the credit because so many people had played a part in developing the ideas behind the project.

"No one person had all the solutions."

"There were one or two people who were far from sure about the idea at meetings through the course of a year but I knew we were going to be successful when I finally heard one of them say to someone after a meeting 'this is fantastic'.

"We all need to work together and I think this has shown us that it's possible."

Oyster revival from shell

* Enterprise Northland believes the reuse, recycling and recovering of oyster shell waste could be undertaken across the country as the shell is a high-quality grade product.

* There are 679 hectares of designated oyster farm areas in Northland, of which 58 per cent (or 395ha) is now 'built'.

* The Kaipara has an estimated 11,000sq m of waste shell and timber.

* The Waikare inlet project will offer final year science students from Auckland University the opportunity to research new "green" industry uses for the crushed shell, such as a filtering medium for cleaning stormwater and dairy effluent. A competition to design a processing plant is also planned for senior students of the School of Architecture, who would pitch their designs in a Dragons' Den type presentation.