‘The sea will always win, despite the actions of people.’ How far do you agree with this view of coastal protection?

(Westminster 2009)

            The small island of Japan has seen several terrible tsunamis in the past twenty years. This includes one that moved the country 3 meters closer to China, and knocked the Earth out of its usual orbit for a day.  This all occurred despite a forty meter high seawall protecting the coast of Tokyo.  In this case, the sea defeated the Japanese governments greatest effort, but will this always be the case?

            On the one hand, the sea can always erode any seawall or blockade we place in its way.  It can, after many long centuries, even wear its way through the thickest of seawalls. Even rivers can overcome dredging after a long time. The Thames could actually overcome its embankments in a century. If a mere river, with minimal wave power, can overcome a multibillionaire defense, then the sea has much greater potential.  It has the power of abrasion, attrition, corrosion and hydraulic action as well as the tide.

            Furthermore, the sea will remain where it is for much longer than any seawall can stand. For all geographers can tell us, the sea and oceans may not change general position for another million years. Even if we were to build a seawall that could withstand erosion, it would be weathered away by other processes, including plant growth or acid rain.  Thus, even with minimal wave power, the sea could potentially get past even the thickest of barriers.

            However, it is entirely plausible that humans may be able to devise a way of blockading the sea efficiently and effectively.  For example, groynes tend to be located along beaches to prevent an excess of longshore drift so that the beach remains. Also, another form of protection is boulder armor.  This is very effective against small waves but not so much against a tsunami.

            On balance, it seems to be the case that the sea will always win, as it can overcome any seawall ever built, but it is still possible that humans will find a new form of coastal protection from the sea.