What is proposed?

The proposed Cairns Shipping (Trinity Inlet) Development Project would mean digging up over at least 4.4 million m3 of dredge spoil. Dredge spoil, the mud and other sediment removed from the sea floor, often contains heavy metals, acid sulphate soils and other contaminants from industrial land uses and shipping. Options for dredge spoil disposal include dumping in the Great Barrier Reef Marine Park or onshore dumping options, both of which pose risks to marine life by increasing sediment and nutrient loads and introducing contaminants.

dredge spoil disposal options map

dredge spoil disposal options map

It is crucial to note that the proposed impact of Cairns Port expansion is not a ‘once off’ as a huge increase in annual maintenance dredging would be required to keep the deeper channel open. This would mean more dredging and release of dredge spoil every year, permanently.


What are the potential impacts on fishing?

Healthy fish and fishing relies on healthy marine environments. Our commercial fishing industry, recreational pastime and fishing tourism industry are all at risk from poor water quality.

Leading Australian scientists in a ‘declaration by concerned scientists on industrial development of the Great Barrier Reef coast’ statement endorsed by hundreds of expert scientists have made it clear that increased sediment and nutrient loads are a key cause of decreased water quality leading to a “very serious decline in the quality of the Great Barrier Reef’s inshore habitats and the abundance of key species.” [i] Poor water quality leads to increased crown of thorn starfish numbers and poor reef recovery from storms, cyclones and bleaching.

Sediments suspended by dredging can block the light required by seagrass and corals, choke and smother marine life interrupting ecosystem balance and lead to fish disease and even human health problems. Scientists “are concerned about the additional pressures that will be exerted by expansion of coastal ports and industrial development accompanied by a projected near-doubling in shipping, major coastal reclamation works, large-scale seabed dredging and dredge spoil disposal – all either immediately adjacent to, or within the Great Barrier Reef World Heritage Area.”[ii]

 releasing a GT

Key threats to fishing include:

  • Potential major fish kills such as seen in Gladstone harbour (see below).
  • Re-suspension and mobilisation of contaminants (metals and metalloids including persistent antifouling chemicals) from sediments.
  • Increased parasitism due to stress, immunosuppression and external irritation from poor water quality and toxicoses.
  • Increased underwater noise impacting on fish behaviour, including feeding and breeding.
  • Generation of toxic algal blooms due to disturbance of sediments and release of nitrogen, iron and other nutrients.[iii]
  • Damage to fish and prawn nursery habitat including reef, seagrass and mangroves reducing overall fish numbers.
  • The unseen and difficult to record impact on planktonic larvae of crustacea and fish.
  • Potential exposure of acid sulphate soils (causing acidification of water).

The Gladstone experience

Diseased Barramundi after dredging in Gladstone Harbour, insets dead dugong and turtle from after Gladstone dredging. Source ABC, credits, Gladstone fish market, ABC TV, Tony Falzon.

Diseased Barramundi after dredging in Gladstone Harbour, insets dead dugong and turtle from after Gladstone dredging. Source ABC, credits, Gladstone fish market, ABC TV, Tony Falzon.

Dredging in Gladstone has been a source of ongoing problems within the Gladstone community and is widely considered the cause of a massive fish kill. The problems escalated from April 2011 until a three-week fishing ban was imposed in September of 2011 due to an outbreak of diseased fish in the harbour.  Fishermen believed the outbreak was caused by contaminants released into the water by dredging activities.  Over 40 fishermen developed health symptoms, including painful boils on their arms and legs after contact with the water[iv].

Presently, a group of over 50 fishermen are seeking $20 million in compensation.  A number of reports and documents have come to light indicating that dredging and a leaking bund wall are the real causes of the fish kill and environmental problems. However there have been no penalties imposed and the local fishing industry may never recover from the real and perceived health risks of eating seafood from Gladstone.

If dredging caused similar problems in Cairns not only our fishing industry, but also our tourism industry could be devastated.


Do we need the Cairns Port Expansion?

The Cairns Port Authority says that the port expansion (dredging) is necessary to allow larger cruise ships to enter the harbour. However large cruise ships already visit Cairns, transferring passengers to the soon to be upgraded facility at Yorkey’s Knob. Such passenger transfers are standard practice  in many cruise ship destinations across the globe.

Looking out over the bay it is clear even to the untrained eye, that Trinity bay is a shallow mud flat and is not a natural deep water port. Waging a constant war with nature to make our port something it is not is a battle that can’t be won and the casualties could be our recreational fishing and commercial fishing and tourism industries – crucial to the Cairns and Far North economy.

Ports North is Government owned and this project is expected to cost over around 80 million dollars for the initial stage, with onshore dumping projected to add up to $200 million to the cost. The increase in annual maintenance dredging would also increase ongoing costs.  Much of the cost would be borne by the taxpayer. Is this the best way to spend your money?

Government is spending millions to help farmers and other land managers to prevent sediment and chemicals reaching the reef. It would be a huge slap in the face to these farmers who are doing the right thing for the Government to now turn around and spend more taxpayers money to undo any gains that have been made. The amount of sediment proposed to be dumped in this port expansion dwarfs the gains being made by investment in improved land management practices.

Given the damage to fish and fishing that occurred after dredging in Gladstone and the ongoing cutbacks to Government agencies responsible for environmental monitoring and enforcement can we really have confidence that history will not repeat here in Cairns?  We need to see continued and increased support to address agricultural, urban and pastoral runoff to the reef and the stopping of new capital dredging programs. Instead we face a fight to protect our far north marine environment and prevent the risk to our tourism and fisheries industries from sediments suspended by dredging proposals for Cairns Port and along the Queensland coast.

What can you do?

This proposal has been ‘flying under the radar’ for too long. We need more discussion and consideration of the risks vs rewards of this controversial proposal.

  • The Environmental Impact Statement for this proposal is due to be released for public comment in late 2014, it is important that community engages in this process and is adequately informed.
  • A community forum on the issue will be held on the 24th September at 6:30pm at the Cairns Choral Society building Greenslopes St Edge Hill.
  • To find out more or arrange a short presentation on the issue for your fishing club or community group contact marine@nullcafnec.org.au
  • Write to and meet your local members of Parliament and Ports North, write letters to the editor, foster discussion in the community.
  • Volunteer to protect the marine environment and our fishing via the Marine Response Team www.marineteam.org

More information on the Cairns Port dredging proposal is available on the CAFNCE website www.cafnec.org.au




[i] Declaration by concerned scientists on industrial development of the Great Barrier Reef coast http://media2.apnonline.com.au/img/media/pdf/Science_statement_020613.pdf

[ii] Declaration by concerned scientists on industrial development of the Great Barrier Reef coast http://media2.apnonline.com.au/img/media/pdf/Science_statement_020613.pdf

[iii] Adapted from: Investigation of the Causes of Aquatic Animal Health Problems in the Gladstone Harbour and Nearshore Waters – Dr Matt Landos BVSc(HonsI) MANZCVSc , 1 October, 2012, Report commissioned by the Gladstone Fishing Research Fund

[iv] Fishing World. (2013, 11 18). Gladstone cover-up exposed. (Yaffa Publishing Group) Retrieved 12 17, 2013, from Fishing World: http://www.fishingworld.com.au/news/gladstone-cover-up-exposed