Marine coastal structures are human-made structures constructed along coastlines to protect the shore from erosion, flooding, and damage from waves and currents. The document discusses different types of coastal structures such as revetments, bulkheads, seawalls, breakwaters, groins, jetties, coastal bridges, dikes, and levees. Each structure type serves a different purpose, such as stopping water, holding soil, protecting infrastructure and navigation channels, and reducing erosion. The document provides details on the purpose, construction, and characteristics of each structure type.

1. WEST BENGAL UNIVERSITY OF ANIMAL AND FISHERY SCIENCES
A SEMINAR ON : MARINE COASTAL STRUCTURES
SUBMITTED TO:
Dr. S.K.Rout
Dept. of AEM
SUBMITTED BY:
Shirsak Mondal
B.F.Sc 1st Year 2nd Sem
FS/2015/31

2. What ARE Marine Coastal
StructureS?
It can be anything human-made in
the coastal area. They are
constructed principally to protect the
coast line.

3. WHAT DO COASTAL STRUCTURES DO ?
1. Stop Water 2.Hold Soil
Protect Infrastructure from flooding due to high
water levels ,erosion and impact from waves and
currents
Protect boat traffic by reducing waves and wave
impact
Stabilize navigation channels by reducing
sedimentation, inlet migration
Reduce erosion by stabilizing shorelines/beaches
Enhance recreation, beauty

4. DIFFERENT TYPES OF COASTAL
STRUCTURES
On the basis of purposes there are different
types of coastal structures.
They are :-
Revetments
Bulkheads and Seawalls
Breakwaters
Groins and jetties
Coastal bridges and piers
Dikes and levees

5. Revetments
Revetments are shoreline structures constructed parallel to
the shoreline
 Revetments are structures placed on bank or cliffs in such a
way as to absorb the energy of incoming water or explosive
caused by water waves and current
A cheaper alternative to sea walls is the revetment ,usually
built for protection

6. •Modern revetments have concrete or shaped blocks of rip
rap stone laid on top of a layer of finer material
•Rip rap has the advantage of good permeability plus it
looks more natural

7. Bulkheads
Bulkheads are vertical retaining walls to hold
or prevent the soil from sliding seaward
It reduces land erosion
Secondary purpose is to protect upland
areas against damage from wave action.

8. Seawalls
It is formed for hard and strong coastal
defence constructed on the inland part of
a coast to reduce the effects of strong
waves
It separate the land & water

9. Curved Sea-wall
Curved or stepped sea walls are
designed to enable wave to break
and to dissipate wave energy and
repel waves back to the sea

10. Seawalls are
vertical
structures
constructed
parallel along
the shore line
It should last
20-30 years

11. Breakwaters
Breakwaters are large scale structures constructed
seaward of, & usually to the shoreline

12. They attempt to break incoming waves
before they reach the shoreline or the facility
(e.g. Marina) they are protecting

13. Single Breakwaters:
Single breakwaters may
be attached or detached ,
depending on what they
are being designed to
protect

14. Groins
Groins are the oldest and most common shore-connected,
beach stabilization structure
They help to create or widen beaches by capturing sand
moving along the shoreline

16. Characteristics of Groins
 they are usually made of tropical hardwoods which are
more resistant to marine borers and erosion
 a few are made of concrete, steel or in more recent
times large rocks
 they are spaced about 50-100 metres apart
 may have a life of 15-20 years

17. Jetties & Piers
a structure extended into a sea, lake or
river to influence the current or tide or to
protect a harbour

18. Coastal Bridges
Pictures of coastal bridges

19. Dikes
dikes are typically earth
structures
 they keep elevated water
levels from flooding interior
lowlands
 sometimes they refer to as
dam

20. River dike