Our work in natural disasters means we are often required to investigate coastal storm damage, erosion, and inundation problems. I joined JBP six months ago as a coastal engineering graduate and was surprised by how frequently our engineers rely on natural materials, which had less emphasis in my engineering degree than concrete and structural courses. One example project is our work to develop a Dune Management Plan for the Burdekin Coastline, where we have had to look towards nature-based approaches to minimise erosion, by developing a natural buffer against storms.
Using spatial analysis we worked to quantify the damage of human activities along the dunes, and to identify weak points which may lead to blowouts. These included areas of dune disturbance, exsting erosion, and informal tracks as a result of human activities (including driving above high tide water level, camping or walking on dune vegetation). We used new numerical modelling to estimate the potential erosion prone area for unvegetated dunes, and identified any at-risk infrastructure and assets.
Above: The Burdekin Dune System dune provides protection to the northern coastal road and the Alva wetlands.
Any at-risk areas were targeted for new sustainable solutions; not using concrete or steel but with ‘soft engineering’ such as the introduction of more dune vegetation, beach widening, new signage and fences to guide beach visitors, and new zones for sand nourishment or beach scraping.
There is a significant contrast of these projects to our typical work in coastal defence structures, where we use rock armour, concrete and steel to construct breakwaters, revetments and groynes. Whilst nature-based options are more suited to providing protection for lower return period storms, they are an economical solution that have a range of ecologic, environmental and social benefits. We are increasingly making them our ‘first-pass’ approach for any coastline, where they can continue to stabilise the beach whilst a larger strategy is formed over several years. They offer an environmental-friendly approach and help preserve our magnificent coastal area.
Above: A dune blowout in Alva Beach