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Coastal Protection for the
Coastline of the Philippines
A case Study for Tacloban and
outlook for Metro-Manila
Wouter de Hamer
25 April 2017
Coastal protection strategy for Tacloban and Palo | 2 June 2016
Typhoon Yolanda
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Coastal protection strategy for Tacloban and Palo | 2 June 2016
November 2013 the largest typhoon ever recorded Yolanda.
NDRRMC confirmed 6,201 identified fatalities, 5,803 of which in Visayas.
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Typhoon Yolanda
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Coastal protection strategy for Tacloban and Palo | 2 June 2016
Coastal Defense Masterplan Tacloban and
Palo Municipality
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Coastal protection strategy for Tacloban and Palo | 2 June 2016
Coastal Protection Strategy
Objectives:
to develop a coastal protection strategy to:
minimize flood risks (loss of life and damage to properties) due to
natural coastal hazards (surge and typhoon waves);
enhance the sustainable development of the coastal zone (develop
natural ecosystems, sustain livelihoods, etc)
Taking into account:
Extreme typhoon events
Expected climate change
Future urban development
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Coastal protection strategy for Tacloban and Palo | 2 June 2016
Coastal Protection Strategy
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Multi-level Safety Approach:
Level 3, resilience and emergency response
Level 2, planning and zoning
Level 1, flood protection, prevention of inundation
Level 3
Level 2
Level 1
Coastal protection strategy for Tacloban and Palo | 2 June 2016
Flood hazards for different Return
Periods
Damages ($/m2) - using damage
functions)
Economic risk ($/m2/year) – area
under the damage probability
curve
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Basis: Flood Risk Damage
Assessment
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Strategy: Non-structural
Strategy: Structural & Non-structural
Strategy: Structural & Non-structural
Translation of Risk to Strategy
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Project area – North Tacloban
No “expensive” structural measures
due to limited marco-economic benefit
Invest in emergency shelters and early
warning to ensure safety of the people
Invest in mangrove expansion and
conversion of fish ponds to improve
resilience.
Only future urban development in flood
free areas
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Strategy: Non-structural
Coastal protection strategy for Tacloban and Palo | 2 June 2016
Project area – Central Tacloban
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Invest in structural measures due to high marco-economic benefit Offshore seawall in the bay area to
minimize social impact Dike along provincial road alignment to the
south to minimize environmental impact Dike along ocean-side of airport to protect
essential infrastructure
Maintain proper drainage from the urban areas and wetlands to the ocean
Design for low maintenance for the dike (no concrete, but earthen dike and armour rock)
Create mangrove education park north-west of airport for education of DRR function soft measures.
Offshore Seawall
Elevated road
Coastal Sea wall
Stru
ctu
ral &
N
on
-str
uct
ura
l Coastal Sea wall
Coastal protection strategy for Tacloban and Palo | 2 June 2016
Mid North - MCA
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A B C
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Coastal protection strategy for Tacloban and Palo | 2 June 2016
Mid South - MCA
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weight factor elevated road sea wall
Technical 10 76% 56%
Socio-economic 70 54% 47%
Environmental 20 80% 20%
61,6 42,8
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Bird’s Eye Impression
Coastal protection strategy for Tacloban and Palo | 2 June 2016
Project area – Palo Municipality
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Only targeted investments in structural
measures to protect urban areas of Palo
Municipality
Invest in emergency shelters and early
warning to ensure safety of the people
Maintain wide openings for the rivers to
freely discharge into the ocean
Invest in mangrove expansion and
conversion of fish ponds to improve
resilience.
Strategy: Structural & Non-structural
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Bird’s Eye Impression
Coastal protection strategy for Tacloban and Palo | 2 June 2016
The proposed strategy is….
A strategy built up from hard measures where necessary and soft
measures where possible, creating a healthy ecosystem and a
protective landscape for the people in and around Tacloban and Palo.
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Coastal protection strategy for Tacloban and Palo | 2 June 2016
Assessment Flood Risk Philippines
Quick Assessment done for LGUs along the eastern
shoreline: over 2500km coastline (158 LGUs) .
Using open source data:
Population density
Flood risk maps (DOST, NAMRIA)
Typhoon tracks (probability)
Conclusions:
Three regions (V, VIII and XIII) at high risk
10 cities (>65,000 people) at high risk
Preliminary emergency plans generally in place
No actual coastal protection strategy exist…
Landuse planning along the coast is key!
For this analysis risk is defined as: “the probability of a flood to occur
multiplied by the damage caused by this flood scenario”.
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Coastal protection strategy for Tacloban and Palo | 2 June 2016
Assessment Flood Risk Philippines
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Coastal protection strategy for Tacloban and Palo | 2 June 2016
Typhoon Pedring (2011)
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Coastal protection strategy for Tacloban and Palo | 2 June 2016
Typhoon Modelling Pedring (Cat. 3)
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Coastal protection strategy for Tacloban and Palo | 2 June 2016
Typhoon Modelling Pedring
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Manila Bay - Multi-level Safety Approach
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Level 3, resilience and emergency response
Most cities have emergency plans in place (mainly
focussing on riverine flooding)
Special/more attention needs to be given to the
most vulnerable people living along the coastline
Level 2, planning and zoning
Overall Masterplan for Manila Bay is lacking
Recent promising initiatives:
NEDA: Manila Bay Sustainable Masterplan
PRA: Programmatic EIA and DSS Manila Bay
Level 1, flood protection, prevention of inundation
Hard measures: implemented on LGU level
(questionable if these are all “future proof”)
Soft measures: non-existing (mangrove and
wetlands areas degraded in most parts)
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Manila Bay’s Issues on Planning (Level 2)
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High pressures on ecosystem due to rapidly increasing
population / urban sprawl :
Untreated wastewater discharges in Manila Bay
Overload of solid waste dumped in Manila Bay
Overfishing / Uncontrolled development of fishponds
Unregulated/illegal (land) developments
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Manila Bay: modern example of “Tragedy
of the Commons”?
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Hardin (1968); “user pursues its own (short-term) benefits over
the (long-term) common benefit to maintain a healthy ecosystem”.
In these cases, literature advises to: improve communication and trust between the stakeholders, steer towards a “regulation-driven win-win situation”.
For the Manila Bay key for success is:
Regulatory and trustworthy government body for Manila Bay Buy-in from private sector Involvement NGOs
Let’s not wait for a Masterplan!
Coastal protection strategy for Tacloban and Palo | 2 June 2016
Thank you for your attention
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