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Policy Brief
Policy paths for addressing coastal erosion in the Philippines Immediate actions needed to curb human activities leading to coastal land loss
Coastal erosion as a national issue Coastal erosion is prevalent in the Philippines (e.g., Fig. 1). As an archipelagic landmass, the loss of coastal lands poses a serious threat to about 60% of the population occupying coastal regions. Typically, long shorelines with narrow coastal plains border the Philippines from large open oceans that are exposed to typhoons. Rapid sea-level rise (higher than the global average) and intensifying storms due to climate change exacerbate the susceptibility of Philippine coasts to erosion. Eroding coasts translate to loss of land that will displace coastal communities and damage industries, ultimately affecting the fragile national economy. Beaches in important tourist sites such as Boracay and Bantayan Island are eroding and, if unmanaged, will continue to do so, eventually impacting revenue in the area.
Call to action. Coastal erosion must be recognized as a national issue. Urgent action from the national government is needed to mitigate man-made causes, and to manage and prepare for the exacerbating effects of climate change. Explicit policies to address this national problem should be put in place.
Human activities exacerbate coastal erosion Human activities speed up the rates of erosion
beyond natural limits. These include unregulated
foreshore development, extraction of beach
materials, abuse of natural habitats, and even the
maladaptive use of hard structures to manage
coastal erosion.
What should be done about it?
• Improve the current easement guideline
• Refine the delineation of seaward limit
• Incorporate easement law into
foreshore development and fisheries
operation
• Enforce easement limit (PD 1067)
• Adopt technical guidelines for the design and
placement of coastal structures (i.e. piers,
seawalls, groins, etc.)
Figure 1. Coastal erosion in Zambales. At the southern flank of Bucao River, as much as 40 m of shoreline eroded after a storm event in 2006.
SAGIP BAYBAY PH
What is the common response to
coastal erosion in the Philippines?
Oftentimes, the default response to
erosional events especially after a typhoon
is the placement of seawalls. However,
seawalls speed up erosion. Over time, the
beach fronting the seawall narrows and
eventually vanishes. Similarly, building of
groins that trap sediments to widen the
beach leads to an undesired consequence
elsewhere: by effectively trapping
sediments on its updrift side, less
sediments can pass through causing
erosion downdrift (Fig. 3a). Solid-based
piers also act like groins (Fig.3b).
Hard structures on the foreshore can
further hasten, rather than arrest, coastal
erosion. What makes things worse is that
these structures are built piecemeal, often
without considering its impacts on adjacent
coastlines.
Figure 2. Caba, La Union after the passage of Typhoon Feria in 2001. Several houses were destroyed by large waves during the onslaught of Typhoon Feria. Erosion persisted even after this typhoon. Stronger typhoons are expected with warming climates.
Unregulated foreshore development, extraction of beach materials, abuse of natural habitats, and even the management of coastal erosion using hard structures (seawalls, groins, solid-based piers and ports) may exacerbate coastal erosion.
Fig. 3a. A groin field along the coast from Agoo to Sto. Tomas in La Union. Rubble groins (top) were constructed in the mid-1980s to arrest erosion resulting in a highly irregular shoreline (right).
Fig. 3b. A solid-based pier in Sta. Fe, Bantayan Island in Cebu acts like a groin. It hinders the transport of sediments leading to accretion updrift and erosion downdrift of the pier.
1. Improve the design and placement of coastal
structures.
Use of solid-based piers and seawalls must
be minimized for coasts to be more resilient.
However, when resorting to such hard
structures, consider the connectivity of
coastal processes, which may extend beyond
municipal or political boundaries.
Evaluate through Environmental Impact
Assessment (EIA) whether the foreshore
structures cause and/ or worsen erosion.
Use geomorphological boundaries such as
continuous coastline or embayment (instead
of political boundaries) when conducting
assessments and/ or planning for coastal
protection.
Figure 4. A geomorphological boundary can be a littoral cell that may consist of an embayment, or a linear beach bounded by rivers or cliffs. Within a littoral cell, the transport of sediments, through the longshore currents, runs uninterrupted. Erosion may occur if, for example, a solid-based pier is built in Municipality C that will hinder riverine materials from reaching the coast of Municipality D since both municipalities are within the same Cell 3. Due to the connectivity of processes within a littoral cell, there should be close coordination in the management of these contiguous coasts.
Figure 5. Pier
built on stilts.
This type of pier
allows sediment
to pass through,
preserving a
continuous
shoreline.
Figure 6. Seawall in Baler, Aurora. This seawall is no match to the strong waves. Its repair and maintenance will be costly.
Apply technical guidelines in designing and
placing foreshore structures, including the
following
o Build ports and piers on coastal segments
where there will be minimal disruption on
longshore drift.
o Build ports and piers on stilts to allow
sediments to pass and reach other coastal
segments.
o Avoid building ports and piers on coral reefs
to minimize harm to the coastal ecosystem.
The loss of coral reefs can affect fisheries as
well as beach stability.
o If seawalls are necessary, consider that
erosion tends to worsen at their front and
along adjacent coasts. Seawalls can also
change the substrate and associated
habitats. Further, they require high initial and
maintenance costs.
What should be done about coastal
erosion?
Addressing coastal erosion calls for minimizing
human activities that speed up beach loss.
Below are some of the actions that can be
considered.
2. Improve the current easement guideline.
o If hard structures are necessary,
combine them with soft measures
such as protection of natural barriers
like coral reef and mangrove.
o If groins are necessary, determine the
net longshore drift because erosion
worsens on the downdrift area.
• Clarify where the seaward limit of the
easement should be reckoned.
The current guideline prescribes simply
“the high-tide line,” but this is variable
with the moon phase. Consider instead a
more fixed alternative such as the
average king tide, which would also
accommodate potential sea-level rise.
• Clarify the definition of the easement or “no-
build zone” in fishery and foreshore lease
agreements.
If invoking accepted terminology, the
“foreshore” is the part of the shore
alternately covered and uncovered by the
ebb and flow of tides and “easement” is
the “no-build zone” landward of the high-
tide line.
PD 1067 (Water Code)
RA 8550 (Fisheries
Code of the Philippines)
? Foreshore lease contract (FLC) / Fishery Lease Agreement (FLA)
Easement
EASEMENT AS DEFINED IN THE WATER CODE OF
THE PHILIPPINES (PD 1067)
“Structures of any kind cannot be built on the banks of rivers and streams and the shores of the seas and lakes throughout their entire length within a zone of three (3) meters in urban areas, twenty (20) meters in agricultural areas and forty (40) meters in forest areas. These zones are subject to the easement of public use only for recreation, navigation, floatation, fishing and salvage.” (PD 1067 (Water Code), Art. 51)
Figure 7. Ambiguity on how the
easement is considered in the
Foreshore Lease Contract (FLC) and
Foreshore Lease Agreement (FLA).
The easement guideline is unclear and not enforced.
Easement is essentially a “no-build zone”. This
guideline addresses the problem of “building too
close to the waterline”, and can provide buffer
against the effects of sea-level rise and storm
waves. In many places, the easement is not
implemented as development is undertaken too
close to the waterline. The poor implementation
of the easement may partly be blamed on vague
definitions of the current guideline. This may be
addressed by the following:
Works Cited: 1. Nicholls, R.J., P.P. Wong, V.R. Burkett, J.O. Codignotto, J.E. Hay, R.F. McLean, S. Ragoonaden and C.D. Woodroffe, 2007: Coastal systems and low-lying areas. Climate Change 2007: Impacts, Adaptation and Vulnerability. Contribution of Working Group II to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, M.L. Parry, O.F. Canziani, J.P. Palutikof, P.J. van der Linden and C.E. Hanson, Eds., Cambridge University Press, Cambridge, UK, 315-356. 2. PNAR. 2013. Coastal Erosion in the Philippines: A National Assessment Report. Submitted to the COBSEA YEOSU Project: Addressing the Challenge of Sea-Level Rise and Coastal Erosion in the East Asian Seas – Initial Implementation of the COBSEA Regional Programme on Coastal Erosion. 3. Siringan, F.P., Sta. Maria, M.Y.Y., and Pang-ot, G. 2006. Coastal erosion in Northern La Union: Trends and possible mitigating measures (unpublished). A terminal report submitted to the Provincial Government of La Union, 102 p National policies and programs Presidential Decree No. 1067 (31 December 1976): The Water Code of the Philippines
Lead Author: Short Bio Dr. Fernando Siringan is a coastal and marine geologist. He has been involved in a wide array of research projects including harmful algal blooms, paleo-climate reconstructions, coastal erosion, submarine groundwater discharge and geophysical mapping of mesophotic corals. For more than two decades, he has spearheaded research on coastal erosion. Dr. Siringan is the current Director of the Marine Science Institute of the University of the Philippines-Diliman.
Co-Authors:
Caroline Marie B. Jaraula. Ph.D. Ma. Yvainne Sta. Maria
Contact details: [email protected]
Fernando P. Siringan, Ph.D. Project Leader DOST-PCAARRD poject, “CEPA and policy review towards improving coastal erosion management in the Philippines”