Imagine driving into a brick wall at 40 mph. Slam! That is going to hurt. You, the car and the wall won’t be in a great state. Now contrast the wall with driving into thick mud and sand. A bumpy ride and a sticky situation, for sure, but I know which of these options I would choose.
Why then, do we so frequently fail to apply this logic to our sea defences? We concrete up the coastline and wonder why our manmade defences fail us in times of storm and high tide. A look at the UK’s coastline after its recent battering tells an important and devastating story; rock and concrete are no match for the power of a violent sea.
When you put concrete in one place, it will provide protection in its direct locality for a certain amount of time, subject to expensive and ongoing maintenance. However, the energy of the sea has to go somewhere, and hard sea defences just create another pinch point further around the coast. It is inevitable, for example, that closing the Thames Barrier increases the overall height of the sea and hence leads to more flooding in places such as Essex.
In recent weeks, scientists have backed Prime Minister David Cameron’s comment linking climate change to the recent “abnormal” weather. Based on this judgement, our region will need to prepare for more tidal and inland flooding in the future.
Concrete hasn’t stood up to its latest test in some places, but there is another way. It is the soft mud approach versus the hard wall. Soft tidal defences such as salt marshes and mudflats help absorb wave energy which then reduces the impact on cliffs or defences behind them. They also provide valuable habitats for wildlife.
Over time, we are losing these soft defences. Gradually, mudflats would shift inland, but hard sea defences prevent this and creates a phenomenon known as ‘coastal squeeze’. It may sound like a romantic cuddle on the beach, but it describes instead the gradual erosion of intertidal habitats up to a sea defence, leading to the sea front being exposed to the full force of the waves.
In the East of England, coastal squeeze is a big problem. The answer is to create new intertidal habitats in suitable locations around the coast, such on the Wash or parts of the Essex coast. Indeed, studies indicate that this would be both an economically and environmentally efficient way of protecting our homes, businesses and biodiversity – even taking into consideration suitable payments for farmers and landowners.
Coastal management will always be a complex science. Many communities would cease to exist without hard seawalls or tidal barriers. We must fight to hang on to these places as long as we can. Meanwhile, being more flexible about other coastal locations, and allowing the sea in, will take the pressure off those on the edge.
If we work with nature, rather than against it, we have a far better chance of protecting our homes and livelihoods. In short; mud, glorious mud, there’s nothing quite like it for soothing the flood.
First published in the EDP and EADT.