3.8 Holderness and coastal erosion

At what rate is Holderness coast disappearing every year?

2 metres per year. Since Roman times it has retreated by 4 km, and at least 29 villages have been lost to the sea.

What are the three main reasons why the coastline at Holderness is retreating so rapidly?

• geology

• fetch

• longshore drift and beach material

Describe the geology of the Holderness coast

• It mostly consists of boulder clay (aka glacial till), which is a mixture of material deposited after the last Ice Age. It is structurally weak with little resistance to erosion

• The more resistant chalk band surrounding the boulder clay has created Flamborough Head

Why is fetch not the main factor that influences the waves at Holderness coast?

Because it is only 500-800 km long, compared to that of 5000 km of those coming from the Atlantic Ocean.

What are the factors that influence the fetch of the waves that hit Holderness coast?

• Currents, which add to the wave energy in the North Sea

• Low pressure weather systems. The air weighs less, raising sea levels which produces higher tides than normal

• Small, mostly enclosed seas often generate huge waves, as they are unable to disperse their energy.

• Sea floor topography

Why are Holderness’ beaches such a huge problem?

Boulder clay produces clay particles, which are fine and easily transported out to sea by suspension. This means there are few beaches to offer friction to absorb wave energy.

How is longshore drift impacting coastal erosion at Holderness?

The tides flow southwards, so longshore drift carries material south, which leaves the cliffs at Holderness poorly protected against wave attack.

Why are sub aerial processes affecting Holderness so badly?

• Freeze-thaw weathering and wetting and drying of boiulder clay are the most common sub-aerial processes at Holderness.

• Slumping is the main form of mass movement at Holderness. The slumped material collects at the cliff base and is then removed by the sea, causing the cliff to retreat.

How are central government agencies and the local government key players on the Holderness coast?

They are jointly responsible for coastal management, however funding for both has been cut since 2010 in order to reduce council tax.

How are stakeholders in the local economy key players on the Holderness coast?

Local businesses, such as those in the agriculture and tourism industry, want greater spending on coastal protection. Insurance companies are increasingly refusing to insure vulnerable properties.

How are environmental stakeholders key players on the Holderness coast?

One of the most important assets of Spurn Head is the protection it gives to the mudflats of the Humber Estuary, so environmental stakeholders argue that a constant flow of sediment is essential to keep the spit intact.

What is terminal groyne syndrome, and how is it impacting the Holderness coast?

It is when higher rates of coastal erosion occur immediately beside those areas that are protected. At Holderness coast, Hornsea is protected by rock armour and groynes, but the beach downdrift at Mappleton is starved of material.

What are the defences at Hornsea?

• The T-shaped rock armour is designed to allow beach sediment to accumulate and pass behind it.

• There were groynes built to trap sediment and stop the beach from eroding, but this starved the beach at Mappleton of sediment.

Give an example of economic loss caused by terminal groyne syndrome.

Golden Sands Holiday Park— there have been an estimated 100 chalets lost to the sea in the last 15 years, which could have meant 400 more people would be visiting the area and helping the local economy.

Why are the social and economic costs of coastal erosion so significant?

Because there is no compensation available for the loss of private property or land caused by coastal erosion in England.

What is the East Riding Coastal Change Fund?

A fund that offers some limited help in terms of financial assistance, as well as free advice for residents affected by coastal erosion. The relocation package can fund:

• the demolition costs for a property

• some relocation costs, up to a maximum of £1000

• the expenses caused by relocating to a new home, up to a maximum of £200