Professor Peter Nielsen, a coastal engineer with the University of Queensland and an international consultant, has been conducting research at Amity Point since 2014. Dramatic erosion events occur there predictably. The rock wall needs regular restructuring as the sand underneath it disappears. His video showed the phenomenon of a flow slide, an event which occurs over a period of two to three hours and at a rate of 30cm/minute.

The shoreline recedes dramatically resulting in a vertical face up to 7m tall. The result is a semicircular bay at the end of the established rock wall. Sand comes back in 2 to 3 weeks to fill in the bay again, but the damage has been done. The long-term effects are not known. Flow slides occur every few weeks, and it is quite an enigma as scientists do not know what triggers them and cannot predict when they will happen next.

Mrs Vivienne Roberts-Thomson is the president of Coochiemudlo Island Coastcare. This is a state education department initiative, where students can go to study Marine Biology and Coastal Erosion. She has won an excellence in teaching award for her work at this centre. There are age specific programs for each year from Prep to year 12. The Centre is in partnership with the Port of Brisbane, looking at the effects of land reclamation. Students map mangroves around White Island and study changes. The pedagogy emphasises discovery, engagement and learning outside the classroom. Practical work for the students includes plankton trawls, drones under water and benthic grabs. This is real life science in action for the students, raising awareness and hopefully inspiring future champions of the bay.

Ms Dianne Aylward is the principal of Moreton Bay Environmental Education Centre. This group started in January 2013 and raises issues and undertakes action plans to protect the island which is part of the Moreton Bay Ramsar Site. The crucial eastern shoreline is the most sensitive to storm damage and erosion. The group works in collaboration with the Redlands City Council and SEQ to conduct mass plantings, sand relocation and dune fencing. There is nearly 20ha of melaleuca wetlands and bush beaches, with over 200 different plant species including some endangered ones. The group has also undertaken a four-year wetland weed eradication program, taking out species like Singapore daisies and replacing them with native species such as marine couch, pigface and spinifex. The Coast Care Group relies on motivated volunteers to share the workload.

After the three speakers had delivered their address, question time was lively, delving further into the concerns and issues and exploring possible solutions. Professor Peter believes that the donation of sand from the Port of Brisbane would be beneficial to counteract global warming on Coochiemudlo Island. The sand would come from the dredging of the 16m deep navigation channel. The proposed development of Toondah Harbour together with the filling in of wetlands would also cause a plume to affect Coochiemudlo Island. Traditionally sand has always moved into Moreton Bay from NSW because of prevailing currents, and there have also been historical storm surges through the decades. However, current development projects are having a massive effect. Scientific research must show the way forward.

The audience benefited from the expertise of these three speakers highlighting different aspects of the impact of coastal erosion. President John Tasker ably moderated the conversation and made the speakers feel at home.

Photo: Kay Rees

Contributed by Stella Rush

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