Types of protection techniques for coastlines:

Types of protection techniques for coastlines:

• Groynes - Fences placed at right angles to the beach to trap sand being moved by longshore drift to create wider beaches to absorb the energy of waves using friction. But it may lead to issues further down the coastline as less sediment gets deposited further down. 25 year lifespan and £1200 per metre costs. Hard engineering

• Sea Wall - A concrete wall that protects towns by absorbing wave energy to protect the cliffs behind them; they usually have curved tops to reflect the waves back out to sea. The walls could create a strong backwash to erode sediment under the wall. They give easy access to the beach for tourists. 100 year lifespan. £5000 per metre (+ any repair work). Hard engineering

• Rock Armour (Rip Rap) - Large boulders piled on the beach to absorb the wave energy to prevent erosion of a beach or cliff and they can be moved as well! They look good and are good for the environment and they last 100-500 years but they cost £1000 per metre. Hard engineering.

• Managed Retreat - THIS DOES NOT STOP EROSION. But it allows some coastal areas to erode and flood naturally. Managed retreat could be farmland or nature reserves (which are low value). It has a varied cost with an unlimited lifespan. It is very friendly to the environment and it looks good as well. Sadly, it is unpopular as rural lands, which ARE TOURIST SITES, are likely to be flooded. Soft engineering

• Gabions - Steel mesh cages filled with boulders to absorb wave energy and are placed near the coast like sea walls. It costs £400 per metre but are average to the environment and ugly. 10 year lifespan but it could hurt tourists if they do touch the sharp cages which is not good for tourism. Hard engineering

• Revetments - Ramps which absorb wave energy and filter sediment through holes but creates a strong backwash on the way down. They give easy access to the beach for tourists. They are average for the environment and cost £2000 per metre. Lifespan: 25-30 years for wooden; 40 years for concrete. Hard engineering

• Beach Replenishment - Basically just replacing the beach; replaces sand that has been washed away and adds new sand. It is good for the environment but it needs to happen constantly and more frequently then the others. £3 - £10 per metre cost. Soft engineering

• Dune Stabilising - Dunes are a natural defence against wave energy but can be time consuming. It is £200 per metre and they are just roots of plants that bind the sand. It is brilliant for the environment and look good and can last forever IF MAINTAINED. Soft engineering.

• Off shore breakwater - Large piles of concrete and cement just off the coast which are parallel to the beach. They break the force of the waves before reaching the beach to stop erosion and they cost £300 per metre. They can vary from 50 to 100 years old but they don’t protect the coasts and only reduces erosion speed. Which means it doesn’t stop it. Hard engineering.