Australian Institute of Marine Science casts doubt on the modelling used to predict the spread of dredge material

This article is more than 6 years old

This article is more than 6 years old

A dredging proposal for the expansion of one of the world's biggest coal terminals near the Great Barrier Reef leaves “significant uncertainty” about the environmental impact of the project, a report undertaken by the Australian Institute of Marine Science has found.



Freedom of Information documents given to the North Queensland Conservation Council reveal the institute was concerned about the modelling used to predict the spread of dredge material as a result of the Abbot Point expansion.



The institute ultimately concluded claims that dredging, dumping and expansion would have little impact were flawed because the impact of ocean currents on sediment movement had never been considered.



They also raised concerns about the accuracy of the monitoring used to assess the impact, the location of monitoring sites, the lack of long-term monitoring and the failure to monitor in areas where sediment moves.



The Great Barrier Reef Marine Park Authority engaged the institute to undertake the review in 2012, with 3 million cubic metres of dredge material to be dumped in the world-heritage listed marine park area.



But despite the institute’s concerns, the authority in January approved the dumping of the material in the marine park.



“Although this dredging activity will be outside of the boundaries of the marine park, substantial amounts of mobile surficial sediment produced by the dredging, suspended sediment and other materials (e.g. nutrients) produced or released by the dredging activity will impact directly upon the marine park,” the review said.



It comes as India’s Adani Group threatens to scrap plans to expand the Abbot Point coal terminal if a suitable dredging site isn’t found soon, because it could incur losses of $1 billion annually from export delays.



North Queensland Conservation Council spokesman Jeremy Tager said the documents raised serious doubts about the modelling and monitoring undertaken by port authorities.

“It’s extraordinary that, in decades of modelling, the impact of ocean currents on sediment movement has never been considered,” he said.



“It’s clear that the modelling done by state-owned ports is likely to have been inaccurate for years, meaning the impacts of dredging and dumping may be underestimated or completely missed.



“This faulty information has been relied upon by decision makers in approving dredging and dumping projects.”



North Queensland Bulk Ports Corporation was not immediately available for comment when contacted by Guardian Australia on Monday afternoon.



On Monday morning the ABC reported the corporation as saying modelling work was ongoing as part of a permit requirement to investigate whether there was a better spot within the marine park to dump the dredge material.



“Hydrodynamic modelling is a tool that is used throughout the entirety of the project,” it told the ABC.

“It is also important to understand that dredging has not yet occurred and there are a number of conditions which will need to be met to ensure that impacts are avoided and mitigated.”

