Working with Nature to Protect the Coast

We don’t have to build “hard” options such as seawalls, groynes or breakwaters to protect our coastline! Can you see the erosion protection in the photo below?

Taking the lead of the dutch whom now aim to “work with nature” in order to protect their coastline, the industry has started to move towards “soft” protection options such as beach nourishment and dune revegetation. These methods have a minimal environmental impact and can be cost effective in certain instances.

To understand how these techniques work with nature we also must understand the natural accretion and erosion cycle of a beach. During summer when there are less storms and smaller waves sand builds up around the shoreline increasing the volume of sand in the dune system which acts as an erosion buffer. Conversely, in winter, there are more storms and more wave energy which result in the removal of sand from this erosion buffer offshore.

This cycle of erosion in winter and accretion in summer can be used to our advantage when trying to protect our coastline. For example, beach nourishment which involves placing sand from an external source on the upper beach face increases the erosion buffer provided by the dune. Another example of working with nature is active dune revegetation, which has two mechanisms by which it improves the erosion buffer of the beach. Firstly it improves the sand capacity on the upper beach face as more wind blown sand is captured due to the presence of vegetation. Secondly the roots of the vegetation act to stabilise the dune thus improving erosion susceptibility.

If your property is at risk of erosion dune revegetation can be a good erosion management option available to you that requires the least amount of approvals.