Holderness coast:

Location: - Located at east coast of England- 60km long

Major features: - Tourism and recreation- Fishing and aquaculture- Agriculture and forestry (high quality agricultural land)- Energy: gas terminals (Easington and Dimlington) account for approx. 20%

of Britain’s gas supply

Geological features: - Mainly cliffs (20-30m high) consisting of soft, boulder clay in bands (horizontally)

- Coast is exposed, approaching waves have a long fetch over the North Sea- Mainly destructive waves eroding the base of the cliff by hydraulic action,

freeze thaw, abrasion, solution, slumping

- Narrow beaches that do not protect the coastline (further threatened by sea-level rise, 6mm per year)

- One of Europe’s fastest eroding coastlines (2m per year), 4km of land have disappeared since Roman times

- About 2 million tonnes of material eroded per year, some villages have completely disappeared

- 3% deposited at spit (Easington)- Mappleton under threat: main road running through the village was 500m

from cliff (1998), now only 50m

Response / defence: - Cost-benefit analysis: costal defences cheaper than building a new road- Hard defences: concrete seawall, timber groynes (encourage the build up of

beach in front of Mappleton by trapping longshore drift)- Possible solution: large underwater reef made of tyres (costly to build, but

they would reduce the amount of energy that approaching waves carry)- Only most valuable areas of land are protected, much of the farmland is given

back to the sea (?managed retreat?)

Problems: - Construction of groyne caused erosion of about 20m per year further along the coast (spit), spit is still being eroded, but no new material can arrive

- Loss of beaches for tourists’ use

Barton-On-Sea:

Location:

- Located at south coast of England

Major features: - First place in England to try rock groynes

Geological features:

- Problems with coastal erosion (1m per year, several buildings have been lost)

- Longshore drift from west to east- Bournemouth (further west) built sea defences no new sediment could

arrive at Barton to protect the cliffs- High energy waves approaching from SW- Cliff is undercut and slumping occurs- Cliff geology: sandstone (porous) on clay (impermeable) water collects

between those two layers, causing sliding

Response / defence: - 1960s: council decided to protect cliff foot by rocks and steel piles (approximate costs: 1 million GBP) (to absorb wave energy)

- 1974: wooden groynes were replaced by rock groynes (they extend 1.8km along the cliff toe) (to trap sand and build a beach to protect the cliffs)

- Costs since 1987 are estimated at 4.5 million GBP

Problems: - Who will pay?- Visual problems – it doesn’t look natural- Rock groynes at Barton trap sand so coast further east is now more easily

eroded

Porlock bay:

Location:

- Bristol channel, Somerset (England)

Major features: - Much of the coastline under care of the National Trust- Saltmarsh is a 185 hectare biological Site of Special Scientific Interest (SSSI)

Geological features: - Coastline includes single ridges, salt marshes and a submerged forest- Shingle ridge which protects the marsh from the sea was weakened due to

high water levels and stormy weather

Response / defence: - Cost-benefit analysis showed that protecting the threatened land was no longer cost efficient (last rebuild of ridge took place in 1990), since then managed retreat

- A new salt marsh developed provides new habitat to animals and protects the land behind from further erosion

Problems: - Some land that was previously used for agricultural purposes is no longer used for farming as it is inundated by the sea at high tides