Coastal Protection Measures
Different types of engineering <ul><li>Hard engineering </li></ul><ul><li>Soft engineering </li></ul>
Hard engineering <ul><li>Seawalls </li></ul><ul><ul><li>Is usually made of concrete which absorbs the energy of the wave  ...
 
 
 
 
Hard engineering <ul><li>Breakwaters </li></ul><ul><ul><li>Usually made of granite. </li></ul></ul><ul><ul><li>Creates a z...
 
 
 
 
Hard engineering <ul><li>Groynes </li></ul><ul><ul><li>Is a low wall built at right angles to prevent materials from being...
 
 
Hard engineering <ul><li>Gabions </li></ul><ul><ul><li>Are used to protect river banks against erosion. </li></ul></ul><ul...
 
 
Soft engineering <ul><li>Stabilising coastal dunes </li></ul><ul><ul><li>The dunes form as a result of the vegetation trap...
 
 
Soft engineering <ul><li>Planting mangroves along the shore </li></ul><ul><ul><li>Mangrove trees have prop roots or kneed ...
 
 
 
Soft engineering <ul><li>Beach nourishment </li></ul><ul><ul><li>This involve adding large amounts of sand to a beach that...
 
 
 
 
Soft engineering <ul><li>Encourage growth of coral reefs </li></ul><ul><ul><li>Coral reefs are masses of rock like substan...
 
 
 
Coastal Protection Management Comparison of the Effectiveness of Coastal Management Protection Measures – Hard Engineering...
Coastal Protection Management Comparison of the Effectiveness of Coastal Management Protection Measures – Hard Engineering...
Coastal Protection Management Comparison of the Effectiveness of Coastal Management Protection Measures – Soft Engineering...
Coastal Protection Management Comparison of the Effectiveness of Coastal Management Protection Measures – Soft Engineering...
Upcoming SlideShare
Loading in...5
×

Sec 3 NA Coastal Protection Measures

11,387

Published on

Published in: Business, Technology
1 Comment
17 Likes
Statistics
Notes
No Downloads
Views
Total Views
11,387
On Slideshare
0
From Embeds
0
Number of Embeds
4
Actions
Shares
0
Downloads
0
Comments
1
Likes
17
Embeds 0
No embeds

No notes for slide

Sec 3 NA Coastal Protection Measures

  1. 1. Coastal Protection Measures
  2. 2. Different types of engineering <ul><li>Hard engineering </li></ul><ul><li>Soft engineering </li></ul>
  3. 3. Hard engineering <ul><li>Seawalls </li></ul><ul><ul><li>Is usually made of concrete which absorbs the energy of the wave </li></ul></ul><ul><ul><li>Protect the coast against strong waves especially during storms </li></ul></ul>
  4. 8. Hard engineering <ul><li>Breakwaters </li></ul><ul><ul><li>Usually made of granite. </li></ul></ul><ul><ul><li>Creates a zone of shallow water between itself and the coast so that waves will break against it before reaching the coast. </li></ul></ul>
  5. 13. Hard engineering <ul><li>Groynes </li></ul><ul><ul><li>Is a low wall built at right angles to prevent materials from being transported away by the longshore drift. </li></ul></ul><ul><ul><li>This enables the transported materials to accumulate on the side of the groyne facing the longshore drift. </li></ul></ul>
  6. 16. Hard engineering <ul><li>Gabions </li></ul><ul><ul><li>Are used to protect river banks against erosion. </li></ul></ul><ul><ul><li>Similarly, these wire cages containing small rocks are used to form a wall to protect other coastal protection structures such as seawalls. </li></ul></ul>
  7. 19. Soft engineering <ul><li>Stabilising coastal dunes </li></ul><ul><ul><li>The dunes form as a result of the vegetation trapping and stabilising the sand. </li></ul></ul><ul><ul><li>The dunes extend several kilometres inland and to height of more than 100 metres. </li></ul></ul><ul><ul><li>Plant vegetation to trap and bind the sand together, preventing sand from being blown away. </li></ul></ul>
  8. 22. Soft engineering <ul><li>Planting mangroves along the shore </li></ul><ul><ul><li>Mangrove trees have prop roots or kneed roots that anchor the trees firmly in the muddy soil. </li></ul></ul><ul><ul><li>These roots also bind the loose soil and protect it from erosion. </li></ul></ul>
  9. 26. Soft engineering <ul><li>Beach nourishment </li></ul><ul><ul><li>This involve adding large amounts of sand to a beach that is being eroded. </li></ul></ul><ul><ul><li>Longshore drift removes the sand from the beach and carries it further down the coast. </li></ul></ul><ul><ul><li>People will bring in sand from other areas and deposit the sand onto the beach again. </li></ul></ul>
  10. 31. Soft engineering <ul><li>Encourage growth of coral reefs </li></ul><ul><ul><li>Coral reefs are masses of rock like substance called corals growing in shallow water. </li></ul></ul><ul><ul><li>They protect beaches against coastal erosion by reducing the speed of the waves approaching the coast. </li></ul></ul><ul><ul><li>Resulting the waves losing most of their energy. </li></ul></ul>
  11. 35. Coastal Protection Management Comparison of the Effectiveness of Coastal Management Protection Measures – Hard Engineering Gabions Groynes Breakwaters Seawalls Disadvantages Advantages
  12. 36. Coastal Protection Management Comparison of the Effectiveness of Coastal Management Protection Measures – Hard Engineering <ul><li>Need regular maintenance </li></ul><ul><li>Weaken wave energy </li></ul><ul><li>Reduce coastal erosion </li></ul>Gabions <ul><li>Erosion on parts of coast not protected by groynes </li></ul><ul><li>Protect coast from high energy waves </li></ul><ul><li>Encourage build-up of beach </li></ul>Groynes <ul><li>Erosion on parts of coast not protected by breakwaters </li></ul><ul><li>Protect coast from high energy waves </li></ul><ul><li>Encourage build-up of beach </li></ul>Breakwaters <ul><li>Erosion may lead to collapse of seawall </li></ul><ul><li>Costly </li></ul><ul><li>Absorb shock of waves </li></ul><ul><li>Reduce erosion of shore </li></ul>Seawalls Disadvantages Advantages
  13. 37. Coastal Protection Management Comparison of the Effectiveness of Coastal Management Protection Measures – Soft Engineering <ul><li>Can affect the depth of coasts – implications for port activities/coastal transportation </li></ul><ul><li>Helps trap sediments to form islands </li></ul><ul><li>Prevents coastal erosion </li></ul>Planting of mangroves <ul><li>Affects investment opportunities in coastal areas </li></ul><ul><li>Allows nature to take its course </li></ul><ul><li>Avoids loss of lives and properties </li></ul>Relocation properties <ul><li>Expensive </li></ul><ul><li>Affects marine ecosystem </li></ul><ul><li>Requires constant supply of new sand </li></ul><ul><li>Improves beach quality </li></ul><ul><li>Improves storm protection </li></ul>Beach nourishment Disadvantages Advantages
  14. 38. Coastal Protection Management Comparison of the Effectiveness of Coastal Management Protection Measures – Soft Engineering - <ul><li>Reduces wave energy </li></ul><ul><li>Encourages the growth of living organisms </li></ul><ul><li>Improves fishing opportunities </li></ul>Growth of coral reefs <ul><li>Dunes are easily eroded if vegetation is not present </li></ul><ul><li>Vegetation growing on dunes anchor sand </li></ul><ul><li>Protects coast from sea </li></ul>Stabilizing dunes Disadvantages Advantages

×