Australian authorities have recently approved plans to dump over one million tonnes of industrial dredge spoil near to the Great Barrier Reef over the next ten years.
Dredging is an industrial process that moves material, or dredge, from one area of the water environment to another. The process has a variety of beneficial uses such as recovering materials of commercial value. It is also essential in coastal redevelopment and in maintaining waterways for port areas.
In 2015, the Australian government banned capital dredging and disposal near the Great Barrier Reef as means to protect the UNESCO World Heritage Site. However, dredging for port maintenance is exempt from this law and in January, the Great Barrier Reef Marine Park Authority (GBRMPA) issued a permit for North Queensland Bulk Ports (NQBP) to dump maintenance dredge within the park’s boundaries.
“Just like roads, shipping channels require maintenance,” said the port authorities in a statement released on their website. “NQBP’s assessment reports found the risks to sensitive marine environments as a result of the maintenance dredging were predominantly low. The permits allow for the long-term, sustainable management of maintenance dredging at the port and will safeguard the efficient operations of one of Australia’s most critical trading ports.”
Experts are worried that this exploitation of a legal loophole will have devastating effects on the reef’s marine wildlife: “Government policy needs to change to ban all offshore dumping, so GBRMPA is not allowed to permit the reef’s waters to be used as a cheaper alternative to treating the sludge and disposing of it safely onshore,” said Greens Senator Larissa Waters in a statement to The Guardian.
“If it’s put in shallow water, it will smother sea life,” Dr Simon Boxall from the National Oceanography Centre Southampton told BBC News. Dr Boxall acknowledged that while dumping the dredge further out in the ocean could lessen the damage, it would still be releasing dangerous materials such as trace metals into the environment. “It’s important they get it right. It’ll cost more money but that’s not the environment’s problem – that’s the port authorities’ problem”.
The granting of the permit has occurred amidst reports that flood waters from Queensland rivers are flowing into the reef, resulting in the freshwater bleaching of corals. These freshwater bleaching events occur because of a decrease in the salinity of the ocean, which provokes a stress response in corals. Bleaching events can also be triggered by increased water temperatures, pollutants, and sedimentation. Algae living in symbiosis with the coral are expelled, causing the coral to turn white in colour. Coral can often survive bleaching events, but increased frequency and intensity of periods of stress often results in mortality.
The Great Barrier Reef is currently experiencing unprecedented back-to-back years of mass bleaching events, giving the reef little time to recover. As global temperature rises and industry grows, the likelihood of a mass extinction is becoming an increasingly real prospect.
A great amount of sea life depends on the coral. Extinction of coral species would have a disastrous domino effect on marine wildlife. This would not only be a tragic loss of one of the world’s most vibrant ecosystems but would have severe socio-economic impacts. Experts warn the economic loss to the fishing and tourism industries will devastate the livelihoods of thousands of individuals.
Since 2016, half of all the coral in the Great Barrier Reef is estimated to have died. This permit to dump port maintenance waste in the reef is “another nail in the coffin,” says Dr Boxall.