A case study of coastal erosion and management on a named coastline, its causes, the strategies used, and their effects (AO1, AO2).

What this dot point is asking

CCEA expects you to learn a named coastline as a case study and to use it to answer questions on why a coast erodes, how it is managed, and the effects and conflicts that result. A precise case study, with named places and figures, is what separates a top answer from a general one. This page uses the Holderness coast in East Yorkshire as a worked example, but the technique applies to whichever coast your school studies.

Why a named coast erodes: Holderness

These three factors, weak rock, powerful waves and a lack of protective beach, are the model for explaining rapid erosion on any coast. Always tie them to named places and a figure for the rate of retreat.

How the coast is managed

Holderness is managed by a mix of defence and doing little, because it is too long and the land too low-value to protect everywhere.

• Protected settlements. Towns such as Hornsea, Withernsea and Mappleton are defended with sea walls, groynes and rock armour to protect homes, businesses and key roads.
• Undefended stretches. Much of the open farmland and small settlements between the towns is left undefended, because the cost of protection would be greater than the value of the land.
• The result. Defences hold the line at the towns, where the beach has built up behind the groynes, but the coast continues to retreat elsewhere.

The effects and the conflict

The management has clear benefits and serious knock-on effects.

• Benefits. High-value property and infrastructure in the defended towns are protected, and the beaches there are wider and safer.
• Knock-on effects. The groynes trap sediment, so the coast immediately downdrift (to the south) is starved of material and erodes even faster, threatening farms, homes and roads there.
• Conflict. People in the unprotected areas feel they are being sacrificed to protect others, while taxpayers question the cost. This is a textbook example of how defending one stretch of coast harms another.

Worked example: deploying the case study

Common mistakes

Examples in context

Example 1. Mappleton and the rock groynes. At Mappleton, rock groynes and rock armour were built to protect the village and the coast road. They worked locally, trapping sediment and widening the beach, but the cliffs just to the south, beyond the protected zone, then eroded faster because they were starved of that sediment. Mappleton is therefore a sharp, named illustration of the central conflict in coastal management: a scheme that succeeds for one place can worsen erosion for its neighbour.

Example 2. Why not defend the whole coast. Defending all 60 kilometres of Holderness would cost far more than the value of the farmland and scattered homes along it, so a decision is made to protect only the higher-value towns. This is a clear, real example of the cost-versus-value judgement at the heart of sustainable coastal management, and it connects this case study directly to the evaluation skills tested in the previous dot point.

Try this

Q1. Why does the Holderness coast erode so quickly? [3 marks]

• Cue. Soft boulder clay cliffs, a long North Sea fetch with destructive waves, and clay washed away rather than forming protective beaches.

Q2. Name two hard engineering methods used to protect Holderness towns. [2 marks]

• Cue. Any two of sea walls, groynes and rock armour (rip-rap).

Q3. What knock-on effect do the groynes cause? [1 mark]

• Cue. They starve the coast downdrift of sediment, so it erodes even faster.