Holderness Coast: A multi-use area

A multi use areas is n area which offers a range of social, economic and environmental activities. Flamborough Head – stunning scenery and birds attracts tourists to visit. Bridlington – provides retirement homes with sea side views. Hull – Every year, 13 million tonnes of imported cargo pass through the port which employs 5000 people. Fishing industry lands fish at Hull docks. Holderness Country Park – provides tourists with a large fishing lake and a dog walking area. Guests can stay in either log cabins or caravans.

Easington Gas Terminal – provides 1000 jobs and 25% of UKs gas supply.

Humber Estuary: off-shore & on-shore wind turbines use strong winds to generate renewable electricity.

Why have coastal areas developed?

Human Activities Economic Activities

• Improved Transport • Improved Transport and Communication • Rising living standards • Available space (e.g. Hull for development • Range of jobs (e.g. Eastington for industry, of industry and housing) Bridlington for tourism). • Large workforce (e.g. Hull which employs • Tourism (scenery and wildlife) (e.g 5000 people in its dockland) Flamborough Head and Spurn Head) • Natural Resources (e.g. fish in Hull, gas in • Attractive place to live (e.g. Bridlington – North Sea piped to Easington) views of the sea) • Tourism (e.g. Hornsea, Bridlington, Various • Second homes/retirement (e.g. caravan and camping sites along the Bridlington) coastline) How is development affecting the environment?

Diesel/oil spillage Industrial units and Some animals and from the tankers may factories have polluted the birds have choked affect marine life; sea causing death of on litter on beaches noise from tankers aquatic life and thus from tourists. disrupting food chains.

Coral reefs (e.g. St Lucia) Conflicts of Interest : are being damaged from Different coastal users who How is development tourists collecting souvenirs make problems for each along the coast and anchors from fishing other. damaging the local vessels. environment? •Oil refineries of S. Humber pollute water for local Footpath erosion at fishermen. Flamborough Head due to high tourist numbers. •Ships coming up R. Humber cause danger for tourist wind-surfers & jet skiers Sea defences along the Holderness Cliff top developments Coastline have stopped the •Wind turbines at Easington have made the cliffs movement of sediment to Spurn can kill migrating birds using unstable which has Head, an important habitat for Spurn for migration. increased rates of erosion. numerous rare birds . How can we protect the coastline? Protection Scheme How does it protect the coastline?

Heritage Coast at -Encourages the use of public transport which reduces cars, congestion, noise and Flamborough Head air pollution - farmers receive extra money through grants if they farm in a way that protects the environment and wildlife biodiversity (range of species) - footpath erosion is reduced by encouraging people to stay on paths through signage Yorkshire Wildlife -Organises seasonal beach cleans at two locations. All rubbish is separated out and Trust at Spurn and recycled where possible which promotes sustainability -Helps to prevent millions of marine animals, birds, turtles and fish dying each year Flamborough Head as a result of entanglement or eating litter floating around in the sea or beach. -Keeps beaches tidy which encourages tourists back into the area.

Greenbelts around -they have prevented new houses and industries from being built land ideal for Bridlington and farming land. -fewer development on cliff-faces has reduced the pressure on cliffs making them Hull more resistant to erosion and weathering. -stopped woodlands and hedges being removed allowing for ecosystems to continue to flourish.

Marine -The MCS has helped reduced overfishing to protect fish stock numbers from Conversation Sites further declining. In the future, it is hoped that fish populations will increase. -The MCS also prevents sand dredging of the sea bed which can damage nesting (MCS) sites of many fish. Constructive and Destructive Waves

What determines the strength of a wave? - Strength of the wind Swash is the Backwash in - How long the wind has been blowing movement of the movement - The distance between the ocean the wave has water up the of water down a crossed (fetch) beach beach

Constructive Waves Destructive Waves Strong Swash, Weak Backwash Weak Swash, Strong Backwash

Deposits rather than erode Erodes rather than deposits

Low wave height (less than 1 metre) High wave height (more than 1 metre)

Low wave frequency High wave frequency.

Erosion and Weathering Key Terms: Erosion – the wearing away of rocks by the action of the sea and their removal Weathering – the breaking up of rocks in situ by the action of the weather, chemicals and biology.

Erosion Weathering

Attrition Wetting/drying Energy from breaking waves causes rocks and Constant wetting and drying causes pebbles to smash into each other They rocks to expand and contract, resulting eventually break down into smaller and in surface cracks and weakening of the rounder pieces rock. Abrasion Materials, like boulders, pebbles and sand are Freeze thaw Weathering hurled against the cliff by breaking waves. Water gets into cracks in rocks and This causes undercutting and the breaking up expands as it freezes, putting pressure of rocks. on the surrounding rock.

Hydraulic Action Corrosion Water is thrown into cracks within the cliff Carbon Dioxide dissolves in rainwater, by breaking waves. Air inside the cracks is producing acid rain. This reacts with squashed by the water and the pressure minerals inside certain rocks (e.g. inside increases limestone), causing them to be When the wave sinks back, the pressurised weakened and easily dissolved. air expands explosively. This causes the rocks to shatter so the cracks slowly become bigger and deeper. Erosion on Hard Coastlines Hard Coastline: Headlands and Bays

1) Hard (e.g. chalk) 4) As the headland and soft rock (e.g. juts out to sea, it boulder clay) are receives the full at right angles to force of the waves the coastline. energy. This allows 2) Soft rock is eroded the headland to be at a faster rate by eroded slowly over hydraulic action and time. abrasion. 3) Over time, a bay is formed within the soft rock. The shape of the coastline reduces the energy forming constructive waves. This allows beaches to form. Hard Coastline: Cave, Arches and Stacks Headland

4) Overtime, the base of the stack is eroded by abrasion which then topples over in a storm to form a stump.

1) A cave is formed 2) An arch is formed 3)A stack is formed when the roof of when hydraulic when hydraulic action the arch is weathered by freeze thaw action widens the and abrasion continue to action. This weakens it causing to joints in the rock erode the backwall of a collapse as a rock fall due to gravity. over time. cave all the way through the headland. Hard Coastline: Wave cut notch and wave cut platform

2) The top of the cliff is 4) Cliff collapses due to gravity weakened by freeze as a rockfall. thaw weathering.

5) The cliff slowly retreats back 1) Erosion from the leaving a wave cut platform sea (i.e. abrasion behind. and hydraulic action) start to undercut the cliff base. 3) This wave cut notch increases in size until the weight of the cliff . can no longer be supported. Erosion on Hard Coastlines

ROCKFALLS Process: Freeze thaw weathering is when water enters cracks between rocks and freezes. This causes the water to expand which puts pressure on the surrounding rocks. Over time, it weakens the rock causing it to break up. This causes rock to fall from the cliff face due to gravity as a rockfall.

Landforms A scree slope of fallen rock is formed at the bottom of the cliff face.

Erosion on Soft Coastlines

Process: SLUMPING Slumping is a rapid movement of boulder clay that occurs on a curved slip plane.

It happens when water percolates (soaks into) into the boulder clay until it becomes saturated with water making it heavy. The weight of the cliff above it forces the rock down towards the sea as a mud flow.

Landforms: A step like cliff face is present after the slumping has occurred. Vegetation (originally from the cliff top) will also be present in patches on the cliff face.

LANDSLIDES Process: A landslide is a rapid movement of boulder clay that occurs on a slip plane that is parallel to the cliff face.

It happens when erosion from the sea undercuts the base of the cliff. This destabilises the cliff face causing the clay to slide down the cliff as a landslide.

Landforms: An accumulation of sediment remains at the base of the cliff which is known as a scree slope. How are beaches formed?

Swash Aligned Beach Drift Aligned Beaches (longshore drift) Waves approach the coastline and then break in 3)Backwash moves the 4) Material is picked up parallel to the coastline material straight back again and moved back up down the beach to the the beach as swash. Swash and backwash sea. 6)The sediment move sediment up and 2) Swash moves in a zig-zag down the beach. moves the motion along the material up beach. Over time, Creates an even profile the beach at large amounts of along the shoreline an angle. sediment are moved along the beach. During storms, berms 1) Prevailing wind 5) Backwash brings the (ridges of sediment can direction moves waves material back down the form). onshore at an angle. beach again.

How are spits and bars formed?

e.g. Spurn Head, e.g. Slapton Ley, Holderness Coastline Devon

How is a spit formed? How is a bar formed? 1. Waves carrying material are blown in the 1. Waves carrying material are blown in the direction of the prevailing wind. direction of the prevailing wind. 2. Longshore drift moves material along the 2. Longshore drift moves material along the coast. coast. 3. Where the coastline changes direction, 3. Where the coastline changes direction, material is deposited in water sheltered by material is deposited in water sheltered by the headland. the headland. 4. The material builds upwards and outwards 4. The material builds upwards and outwards to form a spit. to form a spit. 5. A mud flat starts to develop in the 5. The spit continues to grow across the bay sheltered water behind the spit due to less area and joins to the headland to form a erosion. bar. 6. Secondary winds can cause the end of the 6. A lagoon is formed behind the bar. Over spit to curve forming a hooked end time, this is filled up with sediment to form 7. The salt marsh develops on the mud flat in land. the sheltered water. Why are Some areas are protected from Understand that not all areas can be/need to be decisions made the effect of coastal processes. protected. to manage −− Consider the issues associated with the coastal areas? planning, decision making and management of shorelines.

There are different methods that Describe the concept of ‘hard’ and ‘soft’ coastal can be used to protect coastlines engineering. from the effects of natural processes. Use an example(s) to illustrate the methods and issues associated with: −− hard engineering – use of sea walls, rock armour, gabions, tetrapods, cliff drainage, groynes. −− soft engineering – use of beach nourishment, beach recycling, beach re- profiling Replenishing.

Explore the reasons why different methods of coastal management may be appropriate in different locations. Environmental management protects some areas. How can the The sustainability of coastal • Explore the idea of Integrated Coastal Zone management of areas requires the whole of the Management (ICZM) by looking at one example coastal areas coastal zone to be managed of a coastal area in relation to its economic and be increasingly effectively. environmental sustainability. Consider: sustainable? −− the pressures on the area −− the strategies being used to reduce the pressures and ensure the long-term sustainability of the area.

Protecting coastal areas from the • Investigate one example of the use of increasing threat of rising sea managed realignment (retreat). levels will require the −− Describe the methods used. development of different −− Explain how they operate to protect the approaches coastal area from flooding. −− Evaluate the significance of the methods in relation to the increasing risk of coastal Flooding.

Coastal Management

There are 4 Management Options Some areas are in greater need of protection than others. For for each section of coastline: example there are a variety of reasons specifically economic and social (socio-economic) why seaside towns need to be protected. No Active Intervention (do They are places where people live and they are also places where nothing – and let the coast erode) money can be made specifically through tourism. Towns such as Bridlington, Hornsea and Mappleton are in greater need of prrtection Hold the line (intervene to keep than the farmland inbetween, the Easington Gas Terminal also the coastline where it is at present) needs protecting because it is so important in providing gas for the Advance the Line (build defences UK. Locally it also provides jobs. further out from the existing coastline) The whole of the Holderness coast is vulnerable to erosion as it is made of soft rock. This means decisions are made about which bits Managed realignment (develop to hold the line and which areas will have to be allowed to erode defences further inland and permit back. some coastal flooding) The Shoreline Management Plan SMP does this for the UK.

The aim of the Shoreline Management Plan is to identify which areas of coast require protection, and which don’t. By looking at the coast as a whole (a system) planners can make sure that any changes to one part of the coast – will affect other parts in a planned way and not give surprise effects. Hard Engineering Controlled disruption of natural processes by using man-made structures Advantages - Protects the base of cliffs, land and buildings against erosion. Can prevent coastal flooding in some areas.

Disadvantages = Expensive to build. Curved sea walls reflect the energy of the waves back to the sea. This means that the waves remain powerful. Over time the wall may begin to erode. The cost of maintenance is high.

Advantages - Absorb the energy of waves. Allows the build up of a beach.

Disadvantages = Can be expensive to obtain and transport the boulders.

Advantages - Easily installed, cheaper than sea wall Disadvantages - Not very attractive, needs frequent checking & repair, not easy for people to get over to get to beach, may contain rats nests

Advantages = Prevents the movement of beach material along the coast by longshore drift. Allows the build up of a beach. Beaches are a natural defence against erosion and an attraction for tourists.

Disadvantages - Can be seen as unattractive. Costly to build and maintain.

Advantages - Easily installed. Cheaper, than sea wall, deflects wave power Disadvantages - Can be eroded from below easily, needs frequent repair, not very attractive

Revetment

Popular option in Japan – seen to be effective Can be built on-site Allows some waves through – so less ‘reflected’ wave damage

Tetrapods Soft Engineering Working with the natural processes of sea and sand in a more environmentally sustainable way. Using the natural processes to bring about an intended effect.

Beach Re-Cycling Advantages - Adds to tourist amenity by making bigger beach, attractive, works with the natural processes of the coast Disadvantages - Needs frequent renewal of more sand, does not protect cliff face from winter storm waves. Beach Re-Building Advantages - Adds to tourist amenity by making bigger beach, attractive, works with the natural processes of the coast Disadvantages - Needs frequent renewal of more sand, does not protect cliff face from winter storm waves. Beach Replenishment

Sand and gravel is hoovered up by a dredger ship off the coast, and sprayed onto the lower beach at high tide.

At low tide, bulldozers push the material up the beach to raise the height of the beach

This takes place 3 times a year – in early Autumn after the holiday season, in January before the main winter storms, and at Easter just before the holiday season and to correct winter storm damage to the beach. Reasons behind the Beach Replenishment scheme at Pevensey Reason 1 : Almost all of the 150 wooden Groynes had deteriorated and either needed repair or replacement. Both would be very expensive and use a lot of hardwood – which isn’t a sustainable solution. They were removed in 2007. Reason 2 : The beach environment has many valuable plant species and these needed to be protected and encouraged to thrive. Reason 3 : There are many coastal homes looking out over the beach – and their protection, but also their views needed preserving.

Re-profiling Beach Re-profiling

This means changing the gradient of the beach to the best one for absorbing the wave energy.

Winter storms remove lots of the lower beach with their strong backwash.

Bulldozers spread the sand evenly across the beach in Spring to create a more even profile – which is better at absorbing wave energy. Sea Level Rise, Global Warming and Managed Retreat

Climate change is putting increasing pressure on coastal defences as sea levels rise and are predicted to rise further into the future (Holderness = 50cm rise predicted in 50 years) Management options for protecting coasts from rising sea levels consist of : Do nothing – let the sea flood onto land Move entire communities inland onto higher land Build higher defences with sea walls & embankments Plan for Managed Retreat (coastal realignment) 'THIS IS SEEN AS THE PREFERED OPTION

The Humber faces increasing problems from rising sea levels. The existing defences are already starting to become inadequate was breached by a storm surge in 2003. The engineers had to decide whether to repair the breach, or put in a longer term solution. Sea level rises along the Humber estuary are forecast to continue over the next century

Managed realignment involves the construction of new sea walls at a location behind existing sea walls to create parcels of land that can be flooded to create new inter-tidal environments.

Wallasea Island, Essex Location: Wallasea Island is a low-lying coastal island formed at the confluence of the Rivers Crouch and Roach in Essex. What has happened? With the coastal defences in the north of the island crumbling away, the government decided to realign (change the shape of) the northern part of the island by constructing a new embankment (wall) inland (further south) and allow the sea to further break through (breach) the old sea defences.

Benefits:  The new mudflats and salt marsh (created where the defences are breached – see photo) will help protect the new sea wall  They will offer additional protection to the property to the south  The scheme aims (still too early to assess) to bring back bird habitats which were lost to previous development, improve flood defences on the island and create new leisure opportunities

Costs:  The scheme cost taxpayers £7.5 million  Sediment (mud) and vegetation (salt marsh) has not been immediate