PREVENTION &
MITIGATION OF THE
IMPACT OF COASTAL
PROCESSES, LAND
DEVELOPMENT &
WASTE DISPOSAL
CLAIRE E. OGUE
COASTAL PROCESSES
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PRESENTATION
TITLE
COASTAL PROCESSES
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are naturally-occurring
processes that bring alterations
to the coastal zones. They are
interactions of marine,
physical, meteorological,
geological, and biological
events.
PRESENTATION
TITLE
A. COASTAL EROSION
•(or shoreline retreat) is the loss of coastal
lands due to the net removal of sediments
or bedrock from the shoreline.
•common phrase referring to the loss of
subaerial landmass into a sea or lake due
to natural processes such as waves, winds
and tides, or even due to human
interference.
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Coastal erosion can be either a:
•rapid-onset hazard (occurs very
quickly, a period of days to weeks)
•slow-onset hazard (occurring over
many years, or decades to centuries).
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FIVE MAIN PROCESSE WHICH
CAUSES COASTAL EROSION
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1. Corrasion
- happens when waves pick up beach
material (e.g. pebbles) and hurl them at the
base of a cliff.
- the scraping away of a rock by the action
on it of rock fragments moved by wind or
water.
2. Abrasion occurs as breaking waves which
contain sand and larger fragments erode the
shoreline or headland. It is commonly known as
the sand paper effect.
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3. When waves hit the base of a cliff air is
compressed into cracks. When the wave retreats the
air rushes out of the gap. Often this causes cliff
material to break away. This process is known as
hydraulic action.
4. Attrition is when waves cause rocks
and pebbles to bump into each other and
break up.
5. Corrosion/solution is when certain
types of cliff erode as a result of weak
acids in the sea.
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B. SUBMERSION
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Submersion is the sustainable cyclic
portion of coastal erosion where coastal
sediments move from the visible portion of
a beach to the submerged nearshore region,
and later return to the original visible
portion of the beach. The recovery portion
of the sustainable cycle of sediment
behavior is (accretion).
C. SALTWATER INTRUSION
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Saltwater intrusion is the movement of
saline water into freshwater aquifers, which
can lead to groundwater quality degradation,
including drinking water sources, and other
consequences. Saltwater intrusion can
naturally occur in coastal aquifers, owing
to the hydraulic connection between
groundwater and seawater.
Because saline water has a higher
mineral content than freshwater, it is
denser and has a higher water
pressure. As a result, saltwater can
push inland beneath the freshwater.
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COASTAL PROTECTION
Some structures and
methods can help protect the
coasts from erosion and
submersion. They are usually
constructed along the coasts.
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SEAWALLS AND BULKHEADS
are structures that are built parallel to
shores that protect the coasts from wave
actions.
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Seawall
Bulkhead
GROYNES AND JETTIES
are structures that are built perpendicular to
shores to prevent coastal erosion by promoting
beach build-up as they trap sand.
Groynes
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Bulkhead
GROYNES AND JETTIES
are structures that are built perpendicular to
shores to prevent coastal erosion by promoting
beach build-up as they trap sand.
Groynes
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Jetties
BEACH NOURISHMENT
is a method where a large amount of sand is
added to the coasts. This will create a new
beach or widen an existing one. However, this
method is costly which deters communities to
use it.
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Beach Nourishment
SANDBAGS
are used to counteract waves that hit
the shores. They also diminish the
effect of a storm surge that can cause
submersion.
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REDUCING COASTAL
EROSION
Aside from coastal protection,
different ways can be done to reduce
the impact of coastal erosion. Some of
them are less expensive than
constructing structures along the
coasts.
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• Development of infrastructures must be
constructed in safe distances from the coasts.
• Beach dewatering involves pumping out water from
the shores to prevent erosion.
• Artificial seaweeds can be placed in the water near
the coasts to reduce the speed of current that
promote erosion.
• Ban of mining activities near coasts prevents
erosion caused by mining.
• Plant cover and vegetation around coasts aid in
protecting coasts from erosion.
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WAYS TO PREVENT OR
MITIGATE THE IMPACT
OF LAND
DEVELOPMENT, WASTE
DISPOSAL, AND
CONSTRUCTION ON
COAST
CLAIRE E. OGUE
A. COASTAL LAND DEVELOPMENT
• Coastal land development is due to the demand in space,
structures, and facilities that are used for various human
needs. It aggravates the effects of coastal processes. It
increases the incidents of sand mining and sediment runoff
that contribute to coastal erosion.
• In the Philippines, PD 1586 has established the
implementation of Philippine Environmental Impact
Assessment (EIA). EIA allows the determination of the
possible environmental consequences of implementing a
project, and it also plans possible preventive and enhancing
methods for mitigation of the determined risks.
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B. WASTE DISPOSAL
•The increase in development and population
may lead to increased amounts of waste
disposed of in a coastal area. The wastes are
sometimes disposed of in landfills built near the
coasts. The construction of these landfills not
only causes land and water pollution to the
coastal area but also amplifies the effects of
coastal erosion and results in saltwater
intrusion.
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B. WASTE DISPOSAL
•Effective solid waste management
planning and implementation must be
carried out by the residents and users of
coastal areas. Managing solid wastes at the
community level prevents coastal
deterioration. Industrial wastes must also be
properly managed and not released in
coastal areas.
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C. CONSTRUCTION
•Constructions on coasts are
consequences of the increasing land
development in the area. If done
haphazardly, these constructed
infrastructures can cause more harm to
the coast.
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C. CONSTRUCTION
• It is crucial that these structures are built at a safe
distance from the coasts. This ensures both the
structures’ and coasts’ safety. Structures must also have
strong foundations to withstand the coastal harshness
so that they will not deteriorate. It is also suggested that
the buildings be elevated so as not to directly impact
the coastal soil and for their protection against coastal
processes. If possible, reinforcing building envelopes
should be considered to protect the infrastructure and
land from coastal threats.
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COPING WITH SALTWATER
INTRUSION
The following methods help in dealing with saltwater
intrusion.
• Monitoring and assessment ensure effective
management of saltwater intrusion cases.
• Artificial recharges pump freshwater to the reservoir to
prevent saltwater from intruding through the coasts.
• Barriers can be constructed along coasts to prevent
further advancement of saltwater if already present.
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COPING WITH SALTWATER
INTRUSION
• Regulations from governing units aid in coping with
saltwater intrusion. Structures must be regulated to have
a safe distance from the sea to prevent excessive
groundwater extraction from the reservoir that
contributes to saltwater intrusion.
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ASSESSMENT
TIME!
CLAIRE E. OGUE​
THANK YOU