Cairns Port Dredging Proposal – another Gladstone?

Ports North proposes to dredge over 5 million m³ of potentially contaminated mud to expand the Cairns shipping channel. This proposal is known at the Cairns Shipping Development Project. Dredging and dumping of dredge spoil poses many risks to the environment and to our fishing and tourism industries. Dangers include smothering and cutting off light to seagrass beds and coral reefs, and stirring up toxins and acid sulphate soils which can lead to fish kills, disease and toxic mud washing up on our northern beaches.

• Read our Media Release regarding this article here.
• For more background and links to other detailed information on the proposal start here.

What happened when they dredged in Gladstone?

Flowchart – What happened when they dredged Gladstone Harbour?

In 2011 the Gladstone Ports Corporation (GPC) commenced their Western Basin Dredging and Disposal Project (WBDDP) in the Port of Gladstone, Central Queensland. The approval of the project contributed to the decision by UNESCO’s World Heritage Committee to undertake the Reactive Monitoring Mission, a research project resulting in a call to review the Great Barrier Reef’s World Heritage status.¹  The Great Barrier Reef may be put on the World Heritage Area “In Danger” list in June 2014, in part due to Gladstone and other approved or pending dredging proposals.

The project has been a source of ongoing strife within the Gladstone community. 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, which developed on their arms and legs after contact with the water.¹¹

In response, GPC and the Department of Environment and Resource Management (DERM) released several reports claiming the outbreak of disease was not due to dredging activities, but rather a result of flooding events in late 2010 and early 2011. They also maintained that high turbidity levels in the harbour were a result of tidal activity.⁵ An investigation done by Dr. Matt Landos, director of Future Fisheries Veterinary Services, however, found the opposite. His report, commissioned by the Gladstone Fishing Research Fund, linked dredging to disease, parasitism and toxic algal blooms. Furthermore, his report also explained that the freshwater flood could not have been the cause of the disease, as the timing and nature of disease did not support that explanation.⁶

Although GPC released comments refuting Dr. Landos’ research, he quickly dispelled their argument that flooding was the cause of disease, citing a larger flood, which occurred in January 2013 and had not produced similar effects in the harbour.⁷ and the fact that pathologies observed across the range of affected species could not be caused by freshwater.

Cover ups?

For reasons not provided by GPC to the public, the original design for the project’s bund walls (barriers created around the dredge spoil dump area to keep sediments in while clean water filters out) was modified to accommodate the use of a suboptimal geotextile. The original design and placement of the geotextile within the wall was changed so that the geotextile layer rested on the exterior side of the bund wall, resulting in a leak that released sediments containing heavy metals and other toxins into the harbour. The public was not informed of this design flaw for two years; GPC continued to maintain that increased turbidity levels in the harbour were due to tidal activity and the flooding events of 2010.⁸

An application for a transitional environment program lodged in June 2012 confirmed the environmental impact of the original bund wall failure and how an initial response had not fixed the problem. Documents showed that GPC was aware of the extent of the environmental threat posed by the bund wall failure.  However, no fine or punishment has been administered, and no one has been held accountable for the change of the agreed design that caused the bund wall failure.⁸

Another report was also withheld from the public, only released four years after it had been completed. The report, commissioned by Central Queensland University, found effects from tributyltin (a toxic chemical used in anti-fouling paints) were worsening in certain marine species in the harbour. An environmental law expert from the University of Queensland claimed the failure to release the report until now may be a breach of Federal Law, as its findings could have altered the approval process for the project. GPC claimed they did not release the report because of restrictions in their research agreement with the University, however a CQU spokeswoman stated no such restrictions were in place.²

Has the situation been resolved?

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.

Although GPC has put together a compensation package for fishermen willing to apply, QSIA Chairman Michael Gardner says the magnitude of the effects of the project have not been addressed, making the package not only inadequate but an insult to the fishermen and their families.¹⁰ Presently, A group of over 50 fishermen are seeking $20 million in compensation. Their case against GPC will be heard on 20 January in the Planning and Environment Court.³

What are the dredging risks for Cairns?

The Cairns Port Expansion project if approved would have a double impact. First would be the massive impact of the capital works dredging to deepen and widen the channel. Secondly the expanded channel would require a massive increase in the amount of maintenance dredging as currently occurs, an impact that would occur year after year and tip over the edge an environment already struggling to deal with a range of human impacts.

Dredge spoil dumping increases water turbidity (muddiness), which smothers and cuts off light to corals and seagrasses. Our seagrass is in its worst state in recorded history and has not recovered from cyclone Yasi as it should have as revealed in our recent article Seagrass beds at record low – could the port expansion push them over the edge?. The recently released draft strategic assessment for the GBR has identified most of the reef as being in poor health and sediment and nutrient load as a major threat to reef health. Dredge spoil dumped in our region impacts on offshore reefs and would further muddy our Northern beaches.

The mud to be dredged is almost certainly contaminated, and resuspending this sediment into the greater Trinity environment could lead to wildlife, and perhaps even human, health impacts. We only need to look at the outcomes of dredging in Gladstone harbour outlined above to understand the risks associated with this. A healthy marine environment is vital for our tourism and fishing industries and for community wellbeing. It’s not too late to withdraw the Cairns Shipping Development Project proposal and protect the beautiful marine environment we are so lucky to have on our doorstep.