These are different strategies that people have used to slow down the effect of costal erosion.
Hard engineering
Hard engineering is when defences are implemented to reduce the rate of erosion which are designed not to blend into the environment and disrupts the natural processes.
- Groynes- these are wooden barriers which are placed at regular intervals which lie perpendicular to the coastline.these are designed to reduce the transfer settlements via longshore drift and prevent the beach from disappearing.
| Positives | Negatives |
| Cheap | Regular maintenance required, |
| Effective at reducing longshore drift | Restrict access to the beach |
| A form of visual pollution | |
| Reduces the supply of sediment further down the beach hence increasing the rate of erosion further down. |
- Revetments- these are sloping wooden flatforms placed as an additional layer of defence, designed to reduce the impacts of wave energy.
| Positives | Negatives |
|---|---|
| A flexible design | Restricts access to the beach, |
| Cheap | Traps litter and scavenger animals |
- offshore breakwaters- these are artificial rock barriers which extend offshore bars, which are designed to dissipate wave energy.
| Positives | Negatives |
|---|---|
| Effective as it dis dissipates wave energy creating a sheltered environment , | Disrupts natural flows of sediment |
| Recreational activities like fishing. | Traps fish is and other animals |
| Expensive |
- Riprap- these are large boulders which are imported and placed in front of sea walls to create an additional layer of defence.
| Positives | Negatives |
|---|---|
| Absorbs wave energy | Rocks are imported |
| An additional layer of defence | Poses a hazard to humans |
| Flexible design | Expensive for placement and sourcing |
| Attracts scavenger animals. |
- Gabions- these are cages filled with pebbles placed in front of coastlines and cliff faces.
| Positives | Negatives |
|---|---|
| A flexible design, | Metal can rust causing a spillage of rocks |
| Absorbs wave energy, | Attracts litter and scavenger animals |
| Promenade can often be built on top | Poses a hazard to humans |
- Seawalls- these are concrete barriers with a steel reinforced mesh which are a curved and face the sea.
| Positives | Negatives |
|---|---|
| Reflects wave energy | Ineffective against sea level rises |
| Can be placed as an additional layer of defence | Expensive |
Soft engineering
Soft engineering: this is when defences are placed which are designed to not disrupt the natural process is and blends into the environments. These could be split into June regeneration and beach nourishment.
- Dune regeneration- this is when volunteers plants marram grass into embryo June’s to accelerate the process of psammosere succession. The marram grass would continue to trap sediments carried via aioli and deposition, which will lead to the June to continue to accrete and grow. An increase in the size of the dune, would increase its effectiveness as a buffer zone between the sea. This is effective as it’s cheap as the plants are planted by volunteers.Also once fully grown, the area becomes a wildlife habitat which can attract animals into the area. However once planted the area is cordoned off, which means the June cannot be used whilst the vegetation grows. Also there needs to be regular cheque ups on the June often twice a year.
- Beach dredging- this is when heavy machinery is used to remove sediment from the offshore zone, which will increase the depth of the water. Then removed settlement would be placed onto the beach, which will increase the size of the beach a natural layer of defence against waves. Although this would need to be done on a yearly basis especially with an area with constructive waves as the waves will continue to deposit sediment vice suspension. However a deeper offshore zone will lead to an increase in the formation of destructive waves, but would be compensated by the larger beach. And economic trade off is that a dredger would ofton cost 300,000 pounds to hire, but a larger beach may lead to an increase in tourism.
- Beach reprofiling- this is the only strategy which has very little impact on the natural process is as there is no on natural input of sediment like beach dredging has. Are used to push sediment from the foreshore zone to the near shore zone, which would increase the gradient of the beach. This would provide adequate protection against sea level rises, as a steeper gradient would mean that the see would not rise up as far up the beach as before. This can be evidenced in Worthing beach, where reprofiling take place twice a year.
Shoreline Mangement Plan (SMP)
- Managed retreat- this is when a council gives up an area of land to the sea as it may be more costly to defend than the area is worth. Therefore, existing defences are slowly removed this could be evidenced at spurn head along the Holderness coastline.
- Do nothing- the area that is cold into defending is not valuable, thus is left to be inundated and taken over by the natural process.
- Hold the line- hard engineering defences are placed in an area that is deemed valuable.
- Advance the line existing defences which are defending a valuable area is pushed forward towards the sea so that more land is regained for often recreational opportunities or for commercial purposes.