Sea Defences in Isle of Wight

Some sea defences are to be constructed for Ventnor. In the past, gneiss rock armour stones have been sourced from Norway. More recently carboniferous limestone has been sourced from the UK. Discuss the sources of armour stones for the future work of the same type, including their carbon foot print.

On the Isle of Wight shoreline’s there are many examples of sea defences which help protect the island from the sea.

-Gneiss rocks: these rocks were sourced in Norway and litter along the shore lines of Ventnor. They provide a great diffuser of the crashing waves, however they do tend to be pulled back out into the sea over time and they also become heavily eroded due to the PH of the sea water.

-Seawalls: these are a more modern sea defence techniques. They vary from gabions to complete concrete and stone walls which run along the shoreline preventing further erosion of the land as well as any habitants living close to the shore. They cause the wave energy to reduce therefore less damage is done. However a disadvantage of these types of sea defences is they have to undergo regular maintenance checks because the impact of waves can damage and weathering away parts of the seawall.

- Concrete tetrapod’s: these giant concrete “jacks” are not only fun and artistic to look at they also help dissipate the wave energy in Ventnor. These giant structures are created on site and are marked with the date they were cast. Much like the gneiss armour rocks they also get pulled out into the sea and become dislodged from one another due to the energy of the wave.

Since the Isle of Wight has become a tourist spot for people and various trekker’s, lots of money has been spent of preventing the Isle of Wight from disappear into the sea. Many ways of preventing from this happening is sourcing where armour rocks to line the shore with. However these rocks can be laborious in transporting as well as cutting or creating making it more costly.

In the UK there are many companies which sell armour rocks for sea defences and river defences,