Coastal Engineering Defences Quiz

Label the image to illustrate key features and processes of this coast

a

b

c

d

e

evidence of rock fall

nice wide beach

estuary

promenade

gorge

terminal groyne

salt marsh

Match the type of weathering to the image

• Mechanical - or physical weathering

• 
• Biological weathering

• 
• Chemical weathering

• 

What process is most likely happening here

a

Freeze thaw weathering

attrition

Biological weathering

abrasion

What process is most likely happening here

a

Abrasion

Longshore Drift

Biological weathering

Freeze thaw weathering

Add the correct labels to the places

a

b

c

e

groyne

backwash

beach

constructive wave

destructive wave

hydraulic actio

Chemical weathering

Hard or soft engineering

Groups:

(a) Hard engineering

,

(b) Soft engineering

• Gabion

• Dune

• Managed retreat

• Groyne

• Beach nourishment
• Rock armour - or rip rap

• Salt marshes

• Sea wall

Pros and cons of hard engineering

Groups:

(a) Pros

,

(b) Cons

• Longlasting

• Sea walls deflect the energy of the storm waves

• Will need replacing and repairing in the future

• Stops the waves from hitting the cliffs

• Seawalls are expensive

• Groynes can result in beach starvation further down the coast

• Groynes can create long beaches that reduce friction and slow down the energy of the waves

• Can put a promenade at the back to walk on or for small businesses to set yp such as food stalls

• Can sometimes be ugly

• Gabions and rock armour are relatively cheap

Pros and cons of soft engineering

Groups:

(a) Pros

,

(b) Cons

• Kinder to wildlife

• Often cheap

• Can create a wide beach to reduce friction and take energy out of the waves

• Fits in with the natural landscape

• Might need replacing after storms

• Can take time to take effect

• Low value areas are left to erode

• Dredging for beach replenishment can cause offshore damage

• The rock groynes ​ (a)   that would be transported away by longshore drift.  

• ​ (b)   is at the base of the cliffs between the groynes reducing impact of hydraulic action 

• The cliffs have been reprofiled, forming gentle slopes which have been stabilised with ​ (c)     The beach that has built up between the ​ (d)   further halts erosion of the cliffs. The ​ (e)   has been protected along with 50 properties and businesses in Mappleton.

• groynes
• B1242
• trap beach material
• Rock armour
• vegetation.
• sandbags
• concrete walls
• barriers

The erosion rate has increased significantly further south as the material is now trapped within the groynes. This is known as ​ (a)   Therefore there is ​ (b)   to protect the cliffs further south eg. Cowden where the sea attacks the base of the cliffs increasing erosion and mass movement through ​ (c)   There is conflict between the local authority who installed the defences and landowners at Cowden. Sue Earle, the owner of Grange Farm, has seen rates of erosion rise from ​ (d)   since the defences were installed, leading to the loss of the farm and her home. She received little ​ (e)   for this

• terminal groyne syndrome
• no beach
• slumping.
• 1m to 3 m per year
• beach nourishment strategy
• increased tourism
• rocky shoreline erosion
• compensation