The beautiful beaches of Jeju Island, some of the most sought after vacation destinations in Korea, are slowly disappearing. (image: Pixabay)

A prominent landmark facing severe erosion is Korea, Jeju City’s Iho Tewoo Beach, a place famous for its abundance of basalt sand. Comprising of high economic value, it proves to harbour vital healing properties in the dermatology industry as well as its historic significance dating back to 2 million years ago for its unique rock characteristics. Due to erosion, it serves to be a hassle to keep the beach in good condition as the beach is also used to obtain wind energy from the coast, hence limiting the effectiveness of measures implemented as well as the compromisation of marine lives habitats such as seagull crabs. 

  Hence, the short term detriments would include the decrease in recreational activities as the poor condition of the eroded beach would discourage tourists from visiting, and the long term detriments would include a drastic loss in economic value and a general decrease in profits upon the affected industries which relies on the production of basalt salt to the extent that the economy of Korea may also suffer a loss. Furthermore, the marine habitats may also be destroyed and a loss of sea animal species may also be reported

 To sustain the coastal regions, they used beach nourishment as a strategy to replace the places where sand has been eroded from the beach. Sand from other regions are transported to patch up beaches using dump trucks that have been decimated by wind and waves. For instance, twenty-seven 25-ton dump trucks transported sand from the Exclusive Economic Zone (EEZ) of the West Sea in one day alone. The beach was once known as “black sand village” due to its abundance of basalt sand. With the beach now relying on sand from other regions to replace that lost to erosion, it has started to lose its unique ‘black sand’ character. Beaches in Jeju Island have formed over a long period of time as a result of volcanic activity, and have a distinctive sand composition that differs from other regions. However, they are losing their unique characteristics due to the added sand that is dumped on the beaches as part of “preserving the coast” efforts. This will hence discourage people from visiting the beach because of the loss in uniqueness. It is also very expensive and time consuming because time is needed to transport the sand back and forth. This method will also require regular renourishment since nourished beaches tend to erode faster than natural beaches. Hence this proves that the beach nourishment strategy is unfeasible

Thus, we propose that the coastal management strategy used should be hard engineering, using breakwaters to act as a barrier of defence against the strong waves from the sea, reducing the force of the waves and its impact against the unique sandy beaches and important ports in Jeju. An anchorage is only safe if ships anchored there are protected from the force of high winds and powerful waves by some large underwater barrier which they can shelter behind. Hence, breakwaters can protect the shipping ports and harbours of Jeju such as Port Of Jeju and Seongsan Harbor, ensuring a safe and secure place away from strong waves for boats to anchor themselves and for trades to be carried out smoothly. As for the sandy beaches, the breakwaters will allow sediments to be deposited and build up in this zone of water to form beaches. Breakwaters can create isolated areas of water that can be used for recreational purpose. The calm waters are perfect for swimming, boating, waterskiing, and other similar activities. This can even bring in tourism dollars depending on the location.Breakwaters don’t interfere with wildlife habitats. They may change how wave transmission energy occurs, but this does not alter the marine life’s way of life. Thus, the coral reefs in Jeju will not be affected by this coastal management strategy.  Additionally, breakwaters can act as a line of safety where swimmers are not allowed to cross to the other side of breakwater which can ensure a safer swimming and recreational environment for both tourists and locals.  Hence, breakwaters is the best coastal management strategy to manage the erosion of Jeju Island as compared to less effective methods such as beach nourishments. 

In northwest Africa, the coasts are economically important since a large part of the gross domestic product is derived from coastal activities such as fishing, tourism and commerce. In Gambia, the northwest coast of Africa average rates of coastal retreat are between one and two meters per year.However, more serious rates of up to hundreds of metres per year have been observed locally, especially when the process has been created by human activities. 

Short term impacts include salinisation of water and soils, degradation of ecosystems and flooding. Such predictions were reiterated in the fourth Intergovernmental Panel on Climate Change (IPCC) report. Gambia is primarily low-lying and a 1 m rise in sea level could potentially inundate over 8% of the country’s land area. This includes over 61% of current mangroves, 33% of swamps, and over 20% of current lowland rice growing areas. The inundation could effectively drown over 50% of the capital city of Banjul ,rendering it virtually uninhabitable,and the towns of Barra, Jangjabureh and Kuntaur, together with the Port of Banjul, all ferry terminals, and harbour landings along the River Gambia. Hence, a slight rise in sea level could cause and bring about plenty of inconvenience to the residents living in Gambia. Sea level rise could result in the salinization of shallow coastal aquifers, the primary source of potable water for the urban Gambia. Impacts of sea level rise would be compounded by coastal erosion along the 80 km coastline, with potentially negative effects on the tourism industry, which is critical to the economy of the Gambia. Flooding is also a problem with rain water inundating the city, nearby towns and villages, causing damage to infrastructure and disrupting livelihoods.

Coastal erosion brings long term impact such as threatening populations, as they can no longer live close to the coastline due to the nearby cliffs eroding and crumbling at a dangerous rates as well as the water level’s continuous rising.There is encroachment of the sea on historic sites and commercial business such as Cape Point to Banjul Dockyard, Cape Point to Bald, Bald Point to Allahern River in south and some parts of the northern coastal area around Barra.These important sites might be washed out and lost forever due to not enough measures being taken to protect these areas. The beaches in the capital of Banjul are vanishing as they are located near the coast and experienced severe coastal erosion.In some areas, hotels and other tourism facilities no longer have the stability on the as compared to what they had a few years ago. This impacts tourism, as people are no longer able to continue having their vacation hotels by the beach which, in turn, affects the economy of Gambia as lesser tourists would come and spend money.

 

Using sand bags and planting vegetation as a forms of coastal protection methods are most effective for Gambia.Sandbags is soft coastal protection measure which is now largely being implemented by the hotel industry to protect the hotel Infrastructure . The construction of sandbags proves to be a cheaper coastal protection measure. Although this measure is unable to withstand the forces of huge and intense waves,but it will have some impact on the surrounding coastline and would serve as temporary measures until the coastal dynamics are thoroughly understood for the implementation of more concrete measures thus enabling a more holistic approach to the problem of coastline erosion,which is using planting vegetation. The planting vegetation method can take up to a few years to establish, using sandbags as the first approach to coastal management for Gambia will be more feasible and effective.

Planting vegetation is  effective for Gambia as firstly, it is a cheaper option as Gambia is a relatively undeveloped country and planting vegetation would help to cut costs of coastal management. Secondly, it is something everyone can take part in and contribute as all that is required is just land, which Gambia has plenty of, and seeds of appropriate trees to plant. Lastly, it is effective in protecting the coast as the roots of mangroves can help trap and filter out sediments from the tides and also absorb the impact of the waves to aid in reducing erosion. 

The benefits of the coastal management strategies that are chosen  are  that their are soft engineering methods are that it would not destroy or alter the beach significantly like how hard engineering methods will, hence while protecting the beach, it also preserves it.

The Holderness coastline suffers the highest rate of coastal erosion in Europe and mainly consists of soft glacial drift cliffs which have been cut back up to 200m in the last century.The problem is caused by: Strong prevailing northeasterly winds creating longshore drift that moves material south along the coastline. they also undermine the cliffs through abrasion, hydraulic action.

Beaches are narrow providing little protection for the cliffs. It will therefore erode quickly, especially when saturated. Destructive waves are also basing the sides and eroding the cliffs. The short term impacts of coastal erosion in this area is land slides, mud flows, collapse of cliffs and erosion of coastline. While the long term impacts include loss of housing, loss of farms and loss of communication. 

In our opinion, the coast of holderness is worth protecting as16.9 million people live within the coastal zone and the land . The village of Mappleton, perched on a cliff top on the Holderness coast, has approximately 50 properties. Due to the erosion of the cliffs, the village is under threat. 80 000m² of good quality farmland is lost each year which has a huge effect on farmers‘ livelihoods .People have lost homes to erosion; farmers have lost farmland and a dairy farm has been lost. Visitor numbers dropped in Bridlington by over 30% between 1998-2006. In addition,many coastal towns (such as Mappleton, Bridlington and Hornsea) rely on tourism for income, should these towns not be protected from erosion using expensive coastal protection schemes, their trade would diminish and facilities would close down.Furthermore, with loss of jobs, the migration of young people from these coastal towns and villages to areas with higher employment is more likely. Not to mention that shops and schools will close as there is little or no new investment to sustain local communities. Many caravan parks are at risk from erosion eg. Seaside Caravan Park at Ulrome is losing an average of 10 pitches per year. There is a significant loss of infrastructure (roads, communications, houses, drains), and they are still losing at fast rate. If the coast is not protected, the 16,9 million villagers would be greatly affected in many different aspects, hence, it is worth protecting. 

Some changes that can be made to help reduce the rate of erosion. One of them groynes which can help reduce the energy of the waves and collect sediments that can be moved by the longshore drift to slow down the erosion of the coast We believe that it would be a suitable method to sustain and extend beach areas. Another method that we would like to suggest is the Breakwaters. The breakwaters reduces the energy of the waves, thus creating a zone of calm water, and will help reduce the rate of erosion. 

Although the groynes and breakwaters would result in an aesthetically unappealing coast, it is more important to sustain the beach to reduce the impact both economically and socially. Although groynes are expensive, holderness is part of the United Kingdom which is considered a developed country and they would be able to afford it.

Although erosion is a natural process and there is nothing that can be done to stop it from happening completely, the authorities can adopt certain measures to reduce the impact of the damage done by the coastal erosion. These measures can be simultaneously adopted and put into place concurrently to ensure the best possible way to make the beach safe once more.

One way to protect the Yorkshire Coast is by implementing seawall which is a hard-engineering measure. Seawalls are constructed to protect coastlines against wave attack by absorbing wave energy. Most seawalls are made of concrete or stone and are built parallel to the coast. The coastal erosion has affected the land till it has retreated inwards, forming a cliff so it would be useless to enforce measures like breakwaters and groynes which are built off shore as water can still pass through them and eroding at a faster rate as compared to seawalls. Seawalls are built in contact and up against the cliff which directly minimises erosion of coast by the seawater. They act by absorbing the strong energy of waves to protect the coast against immense waves from eroding loose materials. However, seawalls are constantly to build and maintain as constant repairs have to be made to prevent their collapse, but it is a worth investment for the betterment of the people. Although seawalls can erode at the bottom overtime, Yorkshire is wealthy enough to afford regular maintenance of the seawalls. Therefore, seawalls are suitable to be implemented to reduce rate of erosion in Yorkshire.

Another way to preserve the coast is through soft engineering methods like beach nourishment. Beach nourishment slows down the erosion of beaches by using sand from an external source to replenish the sand on a depleted beach.  As coastal erosion has caused erosion of land above many homes, there are land which are barren above the cliff after collapsing of structures, surrounded by the beach. As the land in this barren area serves no purpose at all, sand and other loose materials from the shore platform can be deposited to shore platforms on coasts encircled by residential areas and important structures which are eroding constantly. This widens and restores the coast as well as protecting the structures behind it as well, thus decreasing rate of coastal erosion.

People who are living near the coast will be negatively impacted, and there are a couple of residents residing near the coast of East Ring. When coastal erosion occurs, property will be lost because the coast will retreat inland into the area where people build their property and houses. The residents’ houses would be submerged or crushed underneath the falling rocks. For example, the Environment Agency has uncovered last year that over the next 100 years, 7000 homes would disappear due to coastal erosion in England and Wales. In addition, fertile land near the coast will also be damaged, causing the people to no longer be able to plant vegetation on it. This in turn reduces their crop yield and profits, and over time, would affect the area’s economy as a whole. Lastly, infrastructure near the coast, like roads and lamp posts, would be destroyed. This would cause people who need to use the road to take an alternative route. In the long run, this causes a lot of inconvenience and affects tourism as people would not want to visit a place that has many broken infrastructure and potential danger. 

Due to constant coastal erosion causing frequent and hazardous collapse of land, the coastal area has led to many residents leaving and avoiding this area to live in and resort to living elsewhere. Having to frequently move elsewhere to live can be a great inconvenience to the residents as they have placed money and sentiment into the housing structure on eroding land. Hence, that is why the coastal land is valuable enough to protect. Protecting the coast is also for the safety of visitors and anyone who uses the roads nearby. Additionally, this eroding coast is an iconic symbol of Yorkshire hence, we should not allow erosion to take over the coast completely and we should try to contain the effects of erosion on this coast.  Therefore, with these impacts in mind, the above measures should be taken into consideration and implemented by the authorities. 

The area is now facing severe coastal erosion which is causing many negative impacts to locals. Due to shoreline retreat, which brings beaches into conflict with human infrastructure, the mere threat of coastal erosion is enough to elicit a management response.

Past human impacts, such as sand mining activities, inappropriate management interventions, climate change and sea level rise have been identified as major contributory factors for coastal erosion, flooding and shoreline retreat. This has caused many negative short term and long term impacts to the town, which is really serious as the town has a population size of about 170,000 as of 2012. The amount of people that are at risk to these negative effects are extremely large and hence, these issues have to be addressed quickly.

The short term impacts of erosion are coastal flooding caused by tides and storm surges due to the 2m rise in sea level, resulting in damage to life and property, especially the boats owned by many of the locals. The economic impact of this is not negligible, when property is damaged, money is needed to restore the building. Jobs may be lost temporarily, and income may be negatively affected due to the time lost when boats are being repaired, which may result in social impacts like a lower quality of life, a reduction in “luxurious” items and in extreme cases, perhaps homelessness, if a resident’s home is submerged and damaged. It is to the interests of residents to slow down these effects. Therefore, there is a need to apply coastal protection measures.

The long term impacts means that residents living near the coasts would be affected and might be rendered homeless in the long run. Houses might be submerged under water. Lesser land would be available due to an increase in land use competition due to a retreating coastline where sediments on the beach slowly gets eroded away as well. To avoid these situation, the rate of erosion of the coast has to be reduced. 

Considering that most houses are built near the coasts, in order to preserve the heritage and culture of this area as a fishing village, hard engineering methods would be preferred. 

Firstly, sand mining activities, which has been ongoing, has to stop in order to significantly reduce the rate of erosion caused by humans. Should this continue, beach nourishment is not an option as the sand that has been added will eventually be mined away. Therefore, there is a need to address this issue as not only is it the main cause of the rapid beach erosion, it is stopping a potential solution from being used.

Gabions are wire cages usually filled with crushed rocks. Smaller rocks provides greater flexibility in design which can make it more aesthetically pleasing.  They are piled up along the shore to prevent or reduce coastal erosion by weakening the wave energy. Gabions also absorbs wave energy better than seawalls as gaps between the walls allows water to filter through and a more successful defence against high energy waves. Gabions can be installed at a much quicker rate than concrete, as no footing or curing is required which helps to faster be implemented and reduce coastal erosion. 

Since Ghana is not as well-developed and is a less affluent country, they might not have enough funds to afford for other hard-engineering methods such as seawall, or breakwaters, hence making gabions, of all the methods is the most suitable method due to its cheap costs. Since it is not build out in sea, it will not obstruct the many fishing boats from travelling around the ocean.

However, gabions are prone to vandalism and excessive trampling. As the area is not very affluent, the aesthetic aspect of gabions are not a major concern.

1. Happisburgh 14th century manor house, its Norman church and the country’s only privately operated lighthouse are all set disappear. This suggests that historical sites such as Norman church and the country’s only privately operated lighthouse are vanishing quickly due to coastal erosion. This greatly impacts the local culture and traditional customs which makes up a major part of the people’s lives as historical information and cultural appreciation is lost. Besides, tourism has been affected due to the loss of some tourism attractions.

2. Happisburgh residents near the coastal areas are constantly under the fear of erosion destroying their personal property, such their houses and crops. Residents will not only suffer losses in terms of their income, as have lesser crops to sell, but they will face psychological stress of insuring their houses, and responding to the impacts of erosion.

1.Flooding can cause impact further inland by washing away people’s properties along its way.

2.without proper management method, the residents would pay the costs in form of high death roll, suffering from the lost of family and close friends. 

3.Due to the damage of infrastructure, people’s daily transportation can not be ensured to be safe and efficient.

4.people who lost their home during the possible flooding may not have essential excess of water, food and other necessary needs since the damage could have a large affecting area so that it require more time to respond.

Despite the costs involved, tetrapods are the most effective way to protect the cliffs and the houses on them. This is because they allow water to pass through them; the interlocking positions the tetrapods are stacked in leave gaps. Hence the reduced wave energy, and the fact that water does not really hit much against the tetrapods, will allow the tetrapods to last for extensive periods of time. Even though tetrapods are costly, the tetrapods do not get destroyed easily. Subsequently, large amounts of money can be saved as they do not require much management /repairing. Also, even though tetrapods are considered unsafe, the cliffed area is mainly used for residence at the upper portion of the cliffs.

http://geographical.co.uk/uk/uk/item/798-norfolk-s-disappearing-villagey 

http://www.bgs.ac.uk/landslides/Happisburgh.html 

Geography Coastal Protection Report

Location of Choice: East Eiding of Yorkshire

The cliffs of the East Riding of Yorkshire, where the plain of Holderness meets the North Sea, provide an example of coastal erosion on an observable scale. Although the situation can vary considerably from place to place, from year to year, and within the year, the overall loss of land through cliff recession along this coast is often quoted as being one of the fastest in Europe.

This phenomenon called retreating of cliffs is taking place due to hydraulic action and abrasion that may erode the rock surface, gradually enlarging the crack to form a notch and then a cave that will collapse to leave behind the cliffs. Over time, the cliff will retreat inland and a gently platform appears at the base where the cliff used to be.

The effects are hazardous. In short term, coastline retreats 2 metres per year. This varies from location to location, though, and yearly losses of more than 18m in some places are not unknown. 

Moreover, the retreat of coastline also causes long term effects, especially the loss of properties. More than 200 homes are predicted to slip over cliff edges between Flamborough Head, near Bridlington, and Spurn Point, 45 miles further south. Meanwhile, people living in the Skipsea area are expecting around 20 homes in their village alone to disappear in the next few years. Skipsea residents have had to get used to an ever-changing cliff-top landscape littered with abruptly ending roads, doomed buildings and the half-remnants of once-loved gardens. Environment Agency information uncovered last year suggested 7,000 homes would disappear due to coastal erosion in England and Wales over the next 100 years. More than 800 of these properties will go in the next 20 years, and homeowners living in them now face the prospect of being forced to move to a safer area with no compensation scheme in place. Hence, it is without doubt that the retreat of coastline will cause profound problems for the local residents and may alter their lifestyles permanently.

Here are some protective measures that can be taken into consideration:

Some man-made structures that are along the Holderness coastline can be constructed to defend against enemy invasion. Defences to counter coastal erosion range from simple groynes, or breakwaters, to extensive sea walls. 

Gabions, which are metal enclosures filled with lumps of rock, can be used in places. They are normally piled up along the shore to prevent or reduce coastal erosion by weakening wave energy. They are cheaper than many other methods as well. However, they are really costly and can be damaged easily.

Locations such as Mappleton and the gas terminal at Easington can be protected by lines of granite boulders. This method is also called using breakwaters. They break forces of energy of the waves to protect the coasts and harbour. Sediments can then be deposited and built up in this zone of water to form beaches. Furthermore, calm water zone can be used as sheltered harbour for boats. However, it is almost impossible to construct harbour under a steep cliff. Furthermore, breakwaters are unsightly. Thus, building of breakwater is not an ideal method.

The combination of seawall and tetrapods can be adopted to prevent coastal erosion. Although it is very costly to build seawall and tetrapod, the protection of the villages on the cliff outweighs the expense of building the protection barriers. The seawall can absorb the wave energy and therefore slow down coastal erosion, and the tetrapod can also slow down the flow of water at the foot of the sea wall, which prevents the erosion at beneath the seawall and complement the role of seawall. Since it can provide strongest protection against erosion to cliff, the combination of seawall and tetrapod is the best method.

 

Hopefully, through this method, the problems of the East riding of Yorkshire can be effectively solved and residents can live a better life while being able to enjoy the beautiful landscape.

One of the places facing coastal erosion is The Holderness Coast. The Holderness Coast is a 61 km long stretch of low glacial drift cliffs ranging from 3m to 35m in height, it stretches from Flamborough Head in the north to Spurn Head in the south.The coastline sweeps in a smooth S-shape which is only broken where sea defences have reduced erosion at the protected point and increased it southwards.The Holderness coastline suffers the highest rate of coastal erosion in Europe and mainly consists of soft glacial drift cliffs which have been cut back up to 200m in the last century.

The reason to this phenomenon is the strong prevailing northeasterly winds creating a longshore drift that moves material south along the coastline. Abrasion and hydraulic action also undermine the cliffs which are made of a soft boulder clay.The beaches do not provide enough protection for the cliffs as they are too narrow. This causes the destructive waves to erode the cliffs quickly.

There are short term and long term impacts caused by the coastal erosion. The short term impacts include landslides, mud flows, collapse of cliffs and erosion of coastline. The long term impacts include loss of housing, farms, habitat and communication.

The Holderness Coast is worth protecting as The village of Mappleton, perched on a cliff top on the Holderness coast, has approximately 50 properties. Due to the erosion of the cliffs, the village is under threat. However, some changes that can be made to help reduce the rate of erosion. One of them groynes which can help reduce the energy of the waves and collect sediments that can be moved by the longshore drift to slow down the erosion of the coast We believe that it would be a suitable method to sustain and extend beach areas. Another method that we would like to suggest is the Breakwaters. The breakwaters reduces the energy of the waves, thus creating a zone of calm water, and will help reduce the rate of erosion. 

Eventhough the groynes and breakwaters are unsightly and expensive to build and maintain, they are important in protecting the coast since they can sustain the beach to reduce the impact both economically and socially. 

The phenomenon we have researched on is Coastal erosion. 

We have researched on a coastal village located on Norfolk's North Sea coast. It is known as Happisburgh and has a population of 1400 people living in about 600 houses. The village houses a notable stone church dating from the 14th century, a grand manor house, listed buildings and a famous red and white striped lighthouse. 

Although Happisburgh was once a distance from the sea and separated by Whimpwell, it has long since been eroded away. The reasons for coastal erosion include sea-level rise, climate change and increased storms. The latter may also have increased the rate of erosion. This is shown through the 250 m of land that was lost between 1600 and 1850. Although coastal defences such as gabions, enclosed by bullhead rail piles and timber bracing, natural shingle beaches, concrete seawalls and revetments were introduced and did successfully decreased the rate of coastal erosion, many areas are still tragically damaged as the engineering structures were not stable enough. More recently the village was affected by the tragic floods of 1953 that claimed the lives of 76 Norfolk residents. 

The short term impact of coastal erosion on the citizens of Happisburgh is that they may experience trauma due to the damage done on their surroundings that serves as constant potential danger to them. They may also grieve over their loved ones whom lost their lives due to sudden unpredicted storms and floods. As the rate of erosion increase, many could be evicted from their homes causing them to have to relocate. This can deal psychological damages to the inhabitants as the house can have much sentimental value.

A long term impact of coastal erosion on the environment, is the destabilization of coastal beaches, buildings and roads. This will be a continuous problem faced by the resource managers of Happisburgh which can result in the extensive loss of state money annually to protect the safety of its citizens as money will be needed to repair and maintain many of the amenities and buildings along the coast. 

Also, as the beach gets eroded away, dry upper intertidal zones would be lost disproportionately, reducing the habitat types available and the diversity and abundance of organisms present in the ecosystem of the beach. For example, seabirds such as Gulls will lose their roosting spot as the beach disappears. Consequently, the prey of the Gulls may start to overpopulate as they will no longer have any predator to prey on them. This overpopulation of theirs can disrupt the balance of the ecosystem as a whole, ultimately resulting in the collapse of the ecosystem in the beach of Happisburgh.

A long term impact of coastal erosion on the environment at Happisburgh is the decrease in economy due to the loss of agriculture. As coastal erosion removes areas available for the citizens of Happisburgh to do farming, the produce for the Village decreases. A loss of tourism due to the irreversible impacts of the fast rate of erosion on the coast that causes the natural and beautifully appealing coast to appear damaged and dull will also cause a decrease in economy. This is because coastal erosion removes areas tourists can visit which will reduce the appeal of Happisburgh as a tourist area. This will decrease profits earned by the Village and thus decreases their economy.

The long term impact of coastal erosion on the citizens would be people starting to be more protective of their surroundings and their coastline. They may even request for more effective measures to be implemented by the government.

The coastline of Happisburgh is being eroded and there are valuable properties to protect, hence some form of coastal protection is required. A wide variety of measures have been used in North Norfolk, ranging from natural shingle beaches to concrete seawalls and revetments. However, erosion of the cliffs provided the material on the beaches. By limiting erosion, the creation of new beach material is prevented.

As a result, we have chosen to use rock armour, a hard-engineering structure consisting of large rocks at base of cliff used to absorb wave energy. Rock armour has become increasingly important in coastal defence works over the last 20 years. Hard igneous rock, such as granite, that is exceedingly resistant to erosion, is placed on the beach leaving large void spaces. When waves hit the rock they are only partially reflected, and can flow round the rocks, expending their energy, which reduces scour.

Another advantage of using rock armour is that it is cheap to build and if the rocks are moved during heavy storms, it is easy to replace them in the correct position. To add on, rock armour can also be used to protect the base of seawalls that is an existing measure used in Happisburgh. However, it is unattractive and small-scaled.

All in all, the rate of erosion on the Norfolk's North Sea coast is high. Many factors including soft and varied bedrocks, exposure to storm winds, high tides, rising sea levels, occasional storm surges and a sinking coastline contribute to this. 

As the coastline is important for a range of human activities including residential, tourism, agriculture, some industry and energy-related land uses, it would be beneficial for the coasts to be protected. Also, there are many monuments that contribute to the history of Norfolk’s  North Sea Coast which deserve to be protected.  

Although coastal protection measures, like groynes, have been put in to protect the coast, it is not strong enough to withstand and protect the coast from high rate of erosion and thus, resulting in the damage of irreversible erosion and the need for reparation.

Happisburgh, on Norfolk's North Sea coast, is a village with a population of 1400 people in about 600 houses. The village contains a notable stone church dating from the 14th century, an impressive manor house, listed buildings and a famous red and white striped lighthouse.

The phenomenon occurring at this location is coastal erosion. Happisburgh was once some distance from the sea, parted from the coast by the parish of Whimpwell, long since eroded away. Historic records indicate that over 250 m of land were lost between 1600 and 1850. Houses that used to be over 20 feet (6 m) in the 1600s from the sea now sit at the edge of a cliff and are expected to fall into the sea. This is one of the long term impacts of coastal erosion in Happisburgh. Sea defenses were built in 1959 to slow the erosion. Some short-term effects of coastal erosion in Happisburgh include storms that destroy the beach by causing huge waves that wash away the sediments on the beach. Sand will eventually deposit on these beaches again to repair the parts that have been destroyed by the storms, but this heavily depends on the ability of the grass on the beach to trap sand.

The rapid coastal erosion here is studied so that information is collected on the processes that normally occur over thousands of years in other places. This helps with our understanding of coastal erosion in other places where it is occurring more slowly.The sea shapes the coastal landscape. Coastal erosion is the wearing away and breaking up of rock along the coast. Destructive waves erode the coastline in a number of ways:

The North Norfolk cliffs, which reach a maximum height of 75m, have two main characteristics that influence coastal erosion. Firstly, they are made of soft heterogeneous (varied) materials with a low resistance, which means that they are very vulnerable to wave erosion and mass movements caused by undercutting and secondly, the sand and gravel components of the glacial deposits are permeable, while the clays are impermeable. The impermeable clay can trap water percolating through cliffs, causing it to pond and discharge from the cliff face. This leads to an increase in pore water pressure in the cliff, reduced strength of the cliff, which may cause landsliding. Wave action can undercut these cliffs making them prone to failure, especially on low cliffs (10 metres or so), such as at Happisburgh. On slightly higher cliffs (about 20 metres), from West Runton to Cromer for example, rotational slides occur because the cliff material is not strong enough to maintain the cliff face at steep angles. We have come up with two methods which can be implemented in this area to protect the coast there. The first method which can be used is beach nourishment to allow the beach to protect the cliffs and also reduce the amount of clay on the beach which will trap water and cause the cliffs to erode faster. We also decided to use groynes to help prevent longshore drift from carrying the sand away. Thus, we have decided to use these two methods to protect the coasts of Happisburgh, Norfolk as they are most suitable given the features of the area.

The use of groynes:

A groyne is an active structure extending from the shore into the sea, most often perpendicularly to the shoreline. Catching and trapping of a part of sediment moving in a surf zone (mainly in a longshore direction), as well as reduction of the sediment amount transported seawards, are the principle functions of the groyne. The groynes’ effectiveness increases significantly if they are employed together with other (soft) shore protection measures, like artificial beach nourishment or shore nourishment.  has a history of problems with coastal erosion. Inspections in 2001 and 2004 showed that wave action had caused the removal of significant amounts of sediment from the beach. The sand elevation in front of the sea wall decreased, posing a risk of imminent seawall failure. Investigations showed that a failure of the sea wall would lead to the loss of sections of the esplanade and the road.The solution to this took the form of a major beach nourishment and groyne construction programme along a 600m stretch of the beach, implemented in summer 2006.Similarly, Happisburgh also faced a lot of similar coastal erosion problems.

Thus, groynes can be used as a strategy. Moreover, to protect the other amenities and buildings behind the beach, they can be built up to the end of the town so it is protected while allowing  natural processes to continue beyond the town. Prevent longshore drift, holding the beach in place. Beach provides a buffer zone which reduces cliff erosion.

Pros:

1     Keeps beach in place for tourists

2.    Doesn’t look as unnatural as some other hard management schemes

3.    Relatively easy to maintain

Cons:

Beach nourishment:

Beaches act as the natural sustainable defence system against coastal erosion. The secret to their success lies in the fact they can adapt their shape very quickly to changes in wave energy and also dissipate this energy in minor adjustments of the position of each sand or shingle grain. The beach is therefore able to maintain itself in a dynamic equilibrium with its environment due to the mobility of its sediments. The beach tends to adopt different profiles according to the season. Sand lost during winter storms tends to be deposited off shore forming protective submarine banks, to be transported back on to the beach during low-energy summer sea conditions. Material is lost from the beach due to coastal currents (see below), but a constant source of new sediments is normally supplied from river deposition and coastal erosion. Due to the natural methods of beach nourishment not being able to replenish the beaches fast enough, beach nourishment has to be implemented. 

 

We propose that Happisburgh should also use beach nourishment together with the groynes to effectively prevent and reverse some of the effects of coastal erosion. Beach nourishment becomes more effective when coupled with groynes as the effects of beach nourishment are easily reversed by strong backwash. The groynes help to keep the sediment added in place. Moreover, the combination of these two methods was successfully when applied to Abeerdan beach as mentioned under the section of the ‘Use of groynes’.

 

Pros:

Cons: 

Wamberal, New South Wales. Wamberal is a largely affluent coastal suburb of the Central Coast region of New South Wales, Australia, just north of Terrigal. It is part of the Central Coast Council local government area and is located adjacent to the Wamberal Lagoon.

The suburb has two distinct areas; a coastal strip which includes Wamberal Beach and the Lagoon estuary which houses medium to high density residential properties, as well as a semi-rural area, slightly west of the beach. The latter contains coastal acreages and ridges of bushland which are legislated non-development areas in order to retain the area's ecosystem.

Coastal erosion is the wearing away of land and the removal of beach or dune sediments by wave action, tidal currents, wave currents, drainage or high winds. A catastrophic storm and king tides which occurred on 5 June 2016 caused the coast of Wamberal Beach, New South Wales to erode even more, posing a threat to the residents living there. Wamberal Beach is also a hotspot for severe coastal erosion.

The short term impacts of coastal erosion in Wamberal beach, New South Wales, include loss of properties and loss of lives. An estimation of 7m of the beach was also lost in the walloping of Wamberal, leaving dangerous metal objects exposed and homes threatened.

The long term impact of coastal erosion in Wamberal beach, New South Wales, is trauma from the catastrophic event. The houses may collapse as many of they are now hanging cliff-faced, which may cause the loss of lives of many people.

Since the previous concrete seawall has been damaged by the storm, building another seawall might bring about a similar result if the same catastrophe were to occur again, due to its inability to withstand the immense pressure from storms and waves in Wamberal beach, New South Wales. Hence, I feel that the best coastal management method for this area is a combination of beach nourishment, a soft engineering method, and breakwaters, a hard engineering method.

Beach nourishment involves adding large amounts of sand to a beach that is being eroded. Sand is being brought in from other areas, like another beach or dredged from sea floor, and deposited on the beach that has been eroded, which in this case is Wamberal beach, New South Wales. This can widen and restore the recreational beach as well as protect the structures behind it.

Breakwaters are barriers usually made of granite and are built either parallel to the coast or with one end attached to the coast. It reduces the energy of the waves which protect the coasts and harbour. It also creates a zone of calm water. Sediments can then be deposited and built up in this zone water to form beaches. The calm water zones can also be used as sheltered harbour for boats.

In conclusion, I feel that a combination of beach nourishment and breakwaters should be used as a coastal protection method for Wamberal beach, New South Wales. This is because beach nourishment can make up for the amount of sand lost due to the storm. The breakwaters can reduce damage done by waves and allow sediments to build up, protecting Wamberal beach, New South Wales, against erosion to a certain extend and at the same time the shoreline will not recede as much as before. This will decrease the risk of properties being damaged by strong waves and storms.