V-Walls have the potential to create high quality surf, provide safe swimming zones, mitigate coastal erosion and create new habitat, while being moveable and therefore removable. No other alternative available today can offer such a broad range of advantages.
Over the last year we have continued to develop the Vwall design and run numerical models to analyse how the Vwalls will influence wave interactions and the sediment transport nearby. Our initial report was completed in August 2020 and is available by request. In short it was found that, yes, as we surfers know the waves will reflect off the angled walls and intersect with the oncoming waves to make nice wedge waves where otherwise there would be close-outs. Second to that, it was established that most of the wave energy will be deflected away from the shoreline thereby reducing wave energy in the lee of each structure by up to 87%. ( see PDF V-Wall: Feasibility Assessment) This will not only result in safe swimming zones behind each Vwall but will also assist in decreasing coastal erosion. With high profile erosion hotspots like Collaroy beach in Sydney, and over 1000 properties in NSW alone at some level of risk from erosion, (see PDF Coastal Erosion in NSW Statewide Exposure Assessment report.), the need for a new solution seems obvious.
As you might have noticed we have also developed a sealed or enclosed version of the Vwall which can of course pivot in the same way as the original hinged version, but has the functional benefit of being directly engaged with the seabed. This significantly enhances the stability of the structure in large swells. See V-wall enclosed.
In addition to the wave and current oriented aspects of the Vwall functions, there is also the potential to create new habitat, by altering the outer surfaces of the entire structure. Flat uniform surfaces that predominates coastal infrastructure do allow for sea flora to attach and colonise, but the surfaces are not similar to what occurs naturally. As a result a much less varied range of organisms will attach. Fortunately, alternative surfaces have been developed by companies like Econcretech, where the materials used and the surface patterns created, actually mimic the surfaces and textures of rock and coral. By using such advanced technology on each Vwall, new habitat could be created, thereby increasing the biodiversity of the local coastal region. And of course this would have a secondary advantage of providing new sites for fishing and diving.
See the link below for the PDF prepared by Griffith University which outlines the research completed over the last 12 months in relation to wave reflection and sediment transport.
New work is being done on the engineering assessment which will determine alternative construction types and costings. The results are due towards the end of 2020.