Preparing Singapore Changi Airport for the effects of climate change

Abstract

Airports play an important role in economic growth and are essential hubs for connectivity and trade. With the growth of urban areas, air traffic is increasing consistently, marking the development of regions such as South-East Asia and others. Following cities, most of the major airports are situated in densely populated areas, next to rivers, in deltas and alongside coasts. Many of these urbanised areas are vulnerable to water extremes, which are increased by the effects of climate change, such as sea-level rise, higher temperatures and greater weather extremes. To protect vital infrastructure and ensure future service continuity for airport operations, it is necessary to develop resilience to such risks. Several airports have recognised the threat posed by floods and have started work on flood protection efforts. Some airports are seizing the opportunity to implement climate resilient airport planning. This paper presents one of these frontrunner airports: a whole-of-government adaptation pathway for Singapore Changi Airport.

Full text

54 © HENRY STEWART PUBLICATIONS 1750-1938 JOURNAL OF AIRPORT MANAGEMENT VOL. 14, NO. 1, 54–66 WINTER 2019–20
Preparing Singapore Changi Airport
for the effects of climate change
Received (in revised form): 14th May, 2019
NANCO DOLMAN
Water Resilient Airports, Royal HaskoningDHV
Nanco Dolman, is a leading professional in Water Resilient Airports at Royal HaskoningDHV
with an MSc in civil engineering from Delft University of Technology (1998) and a BLA in
landscape architecture from Amsterdam Academy of Architecture (2008). From 2011 to
2016 Nanco was a part-time Lecturer, adaptive urban development, at Rotterdam University
of Applied Sciences. And from 2015 Nanco has been a UNISDR Resilient Cities advocate.
For over 20 years Nanco has been the Strategic Adviser of Amsterdam Airport Schiphol
for coping with climate change, airport planning and water management. Besides Schiphol,
Nanco is also involved in resilient airport studies internationally, including New Orleans;
JFK, New York; Mexico City; Sydney; and Changi, Singapore.
Nanco Dolman, Water Resilient Airports, Royal HaskoningDHV, Contactweg 47, 1014 AN Amsterdam,
The Netherlands
Tel: (+31) 88 348 9689; E-mail: nanco.dolman@rhdhv.com
PETER VORAGE
Senior Airport Engineer, NACO
Peter Vorage is Senior Airport Engineer at the Netherlands Airport Consultants, a
company of Royal HaskoningDHV. He has over 10 years of professional experience as
an engineering consultant in the aviation sector, driven by his fascination for airports as
complex, multistakeholder and interdisciplinary infrastructure nodes. Peter is positioned
within a team of highly diverse experts working together to innovate and make relevant
contributions to airport developments. As such, he is focused on furthering the
combination of airport sustainability with airport resilience to climate change. Peter has
worked on a broad range of projects for civil aviation authorities, airport authorities
and contractors including airside design development, runway rehabilitation supervision,
construction phase technical assistance and climate change resilience.
Peter Vorage, Airport Engineer, Netherlands Airport Consultants (NACO), Schenkkade 49, 2595 AR
The Hague, The Netherlands
Tel: (+31) 88 348 1313; E-mail: peter.vorage@naco.rhdhv.com
Abstract
Airports play an important role in economic growth and are essential hubs for connectivity and trade. With
the growth of urban areas, air trafc is increasing consistently, marking the development of regions such as
South-East Asia and others. Following cities, most of the major airports are situated in densely populated
areas, next to rivers, in deltas and alongside coasts. Many of these urbanised areas are vulnerable to water
extremes, which are increased by the effects of climate change, such as sea-level rise, higher temperatures
and greater weather extremes. To protect vital infrastructure and ensure future service continuity for
airport operations, it is necessary to develop resilience to such risks. Several airports have recognised the
threat posed by oods and have started work on ood protection efforts. Some airports are seizing the
opportunity to implement climate resilient airport planning. This paper presents one of these frontrunner
airports: a whole-of-government adaptation pathway for Singapore Changi Airport.
Keywords
airports, climate change, resilience, water management, water-sensitive urban design

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AIRPORT GROWTH IN A CHANGING
CLIMATE
Today, over half of the world’s popula-
tion lives in cities. And many of these
cities are subject to a range of risks, of
which water-related hazards account
for 90 per cent of all natural hazards,
and their frequency and intensity are
generally rising.1 The intensive exploita-
tion of land resources close to rivers
has progressively reduced them to con-
trolled narrow canals, which often face
water quality issues and pose a signifi-
cant flood risk during extreme weather
events. In addition, these cities are sub-
ject to coastal flooding because of storm
fronts, hurricanes and sometimes tsuna-
mis. Following cities, most of the major
airports are situated in densely populated
areas, in deltas, close to rivers alongside
coasts.
Climate change risk is a growing con-
cern in aviation, considering the effects
of sea-level rise, storm surges, increase of
extreme rainfall, changes in wind pat-
terns, increase of average and maximum
temperatures, increase in the number of
extreme weather events and increase in
lightning strikes. In its 2016 environmen-
tal report,2 the International Civil Aviation
Organization (ICAO) warned that rising
temperatures caused by greenhouse gas
emissions will increasingly affect the abil-
ity of aircraft to take off. This is already
evident in certain places around the world;
flights out of Phoenix, Arizona, have
reportedly been cancelled when daytime
temperatures are projected to climb to as
high as 120°F (49°C), making it unsafe for
smaller regional aircraft.
Due to their vulnerability to disrup-
tive weather, over 20 major international
airports suffered from flooding in the
last five years3; examples include fluvial
flooding caused by heavy rainfall in the
upstream catchment area of rivers leading
to a severe and long-term impact on asset
availability (Figure 1). Other airports were
affected by coastal flooding due to high
sea-water levels, such as during hurricane
Sandy. The likelihood of such calamities
is expected to increase, exacerbating the
impact on already affected airports as well
as putting at risk those which have so far
not experienced adverse effects caused by
climate change.
Given the significant value of the asset
base at a typical medium- to large-scale
airport, which can run into the billions,
combined with the complexity and
interdependency of the various airport
systems and supply networks, this situ-
ation is undesirable. Several airports in
Europe, in the USA and in Asia have rec-
ognised the threat posed by floods and
have started work on flood protection
efforts; examples include Amsterdam
Schiphol Airport, New Orleans Interna-
tional Airport and Kansai International
Airport.
At the same time aviation capacity
must expand and grow to keep up with
demand. In 2016 worldwide passenger
traffic grew by 8.0 per cent, up from the
7.8 per cent recorded in 2015.4 To p r o -
tect vital infrastructure and ensure future
Figure 1 Impact of fluvial flooding on airport assets
Source: Photo, by Royal HaskoningDHV.

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service continuity for airport opera-
tions, it is necessary to develop resilience
to such risks. Resilience is particularly
important, as airports often provide vital
transport links in the aftermath of natural
disasters. Airport operational continuity,
therefore, in many cases is not only a
purely economic consideration.
As major airports are the engines in
economic growth and essential hubs
for connectivity, airports can acceler-
ate making cities resilient. Moreover,
airports must understand they are in a
position to be ambassadors in making
more resilient areas. And because of their
potential to take a lead, airports could
play an exemplary role in solving water
challenges of cities and its implementa-
tion of climate change adaptation and
mitigation. Some airports are seizing the
opportunity to implement climate resil-
ient airport (CRA) planning. One of
these frontrunner airports is Singapore
Changi Airport, Skytrax World Airport
of the Year 2018.
CLIMATE RESILIENT AIRPORTS —
FRAMEWORK
In October 2014 the United Nations
Framework Convention on Climate
Change5 included the Schiphol Water
Vision 20306 in the Private Sector Ini-
tiative database of adaptation actions.
Building upon its Water Plan 2015,7
Amsterdam Airport Schiphol explored
ambitious and sustainable objectives
as part of a comprehensive adaptation
strategy. This study is an exploration as
well as an adaptation strategy to create
a strong and resilient airport city. The
exploration shows emergencies as well
as joint interests in the Amsterdam met-
ropolitan area. The vision sets out the
ambition and implementation of coping
with climate change, airport city plan-
ning and water management activities
to 2030 and beyond to ensure the most
sustainable use of water across the whole
scope of airport activities.
For the Schiphol Water Vision 2030,
a CRA framework has been developed.
The CRA framework illustrates the rela-
tion between airport water management
and airport planning, which includes
flood resilience (while considering climate
scenarios), implementing water-sensitive
urban-design measures and conducting
spatial and economic development. The
five key ambitions of the CRA (Table 1)
are constructive ambitions that evolve
from an engineered airport to a more
integrated and inclusive water-adaptive
and climate resilient airport.
Due to its high-density urban envi-
ronment and low elevation, Amsterdam
Airport Schiphol is a relevant peer to
Singapore Changi Airport. Both are built
Table 1 Constructive key ambitions of the Climate Resilient Airport
A Flood protection:
Water levels outside ood protection system.
B Dealing with weather extremes:
Storm water drainage and groundwater management.
C Achieving good water quality and a healthy ecosystem:
Implementing blue-green measures and ecosystem services.
D Adaptive airport city planning:
Enhancing airport use and passenger convenience.
E ‘Greening’ airport operations:
Sustainable solutions and innovations to improve local climate and energy management.
Source: Dolman, N. (2016). ‘Creating water sensitive airports in times of climate change’. Proceedings of the Singapore International Water
Week (SIWW).

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on reclaimed land. Singapore Changi
Airport is built on reclaimed land raised
above sea level, while Schiphol is built
in a polder situated approximately 4.5
metres below sea level. Therefore, the
first two key ambitions of the CRA
(ie flood protection and dealing with
weather extremes) were found to be
of immediate relevance to the climate
change study for Changi Airport, build-
ing upon established international best
practice while adapting and developing
to meet the challenges and requirements
of Singapore.
SINGAPORE CONTEXT
When Singapore became independent in
1965, it was a city challenged by pollution
and dependent on agreements with neigh-
bouring Malaysia for the supply of water.
Holding limited land and no natural
resources, it was ranked first among coun-
tries with the greatest risk of high water
stress by 2040 by the World Resources
Institute.8 In 1969, the then prime min-
ister Lee Kuan Yew intervened in the
matter of cleaning Singapore’s highly
polluted watercourses and developing
water self-sufficiency. In a short period of
50 years, Singapore has become a clean,
modern metropolis with a diversified
economy and reliable infrastructure.
With the growth in global aviation
transport, Singapore’s airport at Paya
Lebar experienced rapid traffic growth;
annual passenger numbers rose from
300,000 in 1955 to 1.7 million in 1970
and to 4 million in 1975. Concerned that
the existing airport was in an area with
potential for urban growth, instead of
expanding Paya Lebar, the government
subsequently decided in 1975 to build a
new airport at the eastern tip of the main
island at Changi (Figure 2). The first
phase commenced commercial operation
on 1st July, 1981, and the airport has
been on a track of continuous develop-
ment ever since. In 2018, Changi Airport
handled 65.6 million passengers and 2.15
million tons of cargo, making it one of
the main worldwide aviation hubs and of
key importance to Singapore’s economy
and international connectivity.
The land reclamation areas along the
coast of Singapore have an elevation
several meters above sea level. Changi
Airport is no exception. As climate
change and its effects become increas-
ingly apparent, it is time to assess its
impact on aviation and make the neces-
sary plans. Operational continuity of this
critical infrastructure is of utmost impor-
tance. That is why the Civil Aviation
Authority of Singapore (CAAS) recog-
nises that climate change poses potential
challenges for Changi Airport and its
infrastructure assets and that coordinated
action is required to prepare Changi Air-
port to continue being resilient.
With two-thirds of the island utilis-
ing water catchment methods, Singapore
is one of the few countries in the world to
harvest urban storm water on a large scale
for consumption. The national water
agency Public Utilities Board (PUB)9
calls this closing Singapore’s water loop.
Despite the current success, Singapore
remains a water-stressed nation. Besides
rainwater from local catchments (1st
national tap), Singapore is still import-
ing water from Malaysia (2nd national
tap). To achieve self-sufficiency in its
water resources, Singapore is invest-
ing in NEWater (3rd national tap) and
desalinated water (4th national tap).
Considering the significant surface area
of Changi Airport in combination with
the relatively high yearly rainfall average
of approximately 2,165 mm, the reten-
tion basins required to protect the airport
during extreme weather events have the

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potential to capture up to 10 million
cubic metres of water on a yearly basis.
Given the land use at Changi Airport,
there is a risk of contamination with pol-
lutants; nevertheless, the potential for use
of this fresh water to the benefit of the
nation may be worth pursuing.
METHODOLOGY FOR STRESS TESTING
CLIMATE CHANGE RISK
Recognising the effects of climate
change, CAAS embarked on a climate
change study for Changi Airport in 2016.
The climate change study was carried
out under the auspices of the Govern-
ment’s Resilience Working Group, an
interagency committee that includes the
PUB, Building & Construction Author-
ity (BCA) and National Environment
Agency (NEA) as its members. The
multiagency structure exemplifies Singa-
pore’s holistic approach towards climate
change and has enabled CAAS to tap
into the subject matter expertise of PUB,
BCA and NEA’s Centre for Climate
Research Singapore (CCRS).
Climate resilience at airports is about
dealing with the vulnerability of airport
infrastructure and operations to disruptive
weather. With the extensive involvement
of government and airport stakeholders,
CAAS and Netherlands Airport Consul-
tants (NACO) developed an innovative
methodology to map and mitigate airport
climate change risks (Figure 3).
A benchmark study was conducted,
which examined how the Singapore
Changi Airport is performing com-
pared with its international peers in
terms of dealing with climate change
risks. It concluded that many airports
Figure 2 Situation of Changi Airport at coast of mainland Singapore

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face challenges related to climate change,
such as an increasing risk of flooding
during extreme weather events. Interest-
ingly, the number of airports making a
concerted effort to mitigate these risks is
still relatively limited.
Based on climate projections, nor-
mative scenarios were determined.
The vulnerability of critical airport
assets was identified, assessing the risks
through scenario-based modelling
and formulating climate change adap-
tation measures to address identified
risks. Finally, a long-term, incremen-
tal and flexible whole-of-government
adaptation pathway was defined for
Changi Airport to enhance its resilience
to climate change.
RELEVANT CLIMATE VECTORS AND
PHYSICAL ENVIRONMENT
Airports are vulnerable to the effects of
climate change in three distinct ways.
First, airport infrastructure is especially
vulnerable to the effects of the anticipated
increase in extreme precipitation inten-
sity as well as sea-level rise and storm
surges. This is particularly true because
the effects of climate change were not
Figure 3 Methodology of Singapore Changi Airport climate change study.

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taken into consideration during the
design of legacy infrastructure. Unavail-
ability of critical assets is likely to have
a knock-on effect on airport operations.
Secondly, airport operations may be
directly affected by climate change in
multiple ways. For example, changes in
wind direction and speed may lead to
an increase in crosswind operations and
ultimately reduce the runway usability,
while extreme wind phenomena such as
wind shear have the potential to nega-
tively impact flight operations. Changes
to visibility and cloud base could result
in an increase in instrument approaches,
potentially reducing runway capacity.
An increase in air temperature results
in a decrease in lift, resulting in pos-
sible payload restrictions, while extreme
temperatures may exceed the flashpoint
of aviation fuel or in exceptional cases
the temperature-altitude envelope of an
aircraft. A reduction in visibility and
potential loss of friction on the runway
could result from an increased likelihood
of extreme rainfall events. And finally,
changes in lightning frequency and
intensity would result in more frequent
cessation of airport operations to safe-
guard safety of service personnel.
Thirdly, tertiary effects caused by
climate change may influence airport
operations. Changes in bird populations
and migratory patterns as well as changes
to transboundary smoke haze fall into
this categor y.
The climate change study carried
out for Changi Airport established that
in this case, the possible changes in risk
levels as caused by the direct impact of
climate change on airport operations is
deemed to be primarily low. The main
reason was the relatively moderate rate
of change as compared to the rapid pace
of technological advance in airframe
development. The same conclusion was
reached for the tertiary effects. On the
other hand, the airport infrastructure
was found to be exposed to a relevant
risk profile that gets more distinct over
time. With flood risk being a concern
for Changi Airport due to its coastal
location and having been partly built
on reclaimed land, the focus of the cli-
mate change study was on assessing the
impact of increased rainfall intensity and
sea-level rise. A study by the CCRS10 in
collaboration with the United Kingdom’s
Met Office Hadley Centre projected that
Singapore is likely to experience heavier
storms and face rising sea levels. CAAS
and NACO undertook a series of con-
sultations with PUB, BCA and CCRS
to establish the input parameters. These
included:
1. The timeframe to be considered
2. Return period for rainfall and storm
surge events
3. The extent of future increases in rain-
fall intensity and extent of sea-level rise
A return period refers to an average
recurrence interval over an extended
period of time and is an estimate of the
likelihood of an event (such as a storm) to
occur. Thus, a storm with a return period
of 50 years has a 1 in 50 or 2 per cent
chance of occurring in any one year. And
in Singapore’s context, storm surge is a
consequence of strong persistent winds
during the monsoon seasons, causing a
surge in the sea level.
In that regard, in terms of study mile-
stones, 2030 was taken as the short-term,
2050 as the medium-term and 2100 as
long-term scenarios, in line with the
Intergovernmental Panel on Climate
Change’s (IPCC) description of early
century (2010–2039), midcentury (2040–
2069) and end centur y (2070–2099) in its
Fifth Assessment Report.11 Addition a lly,

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with Changi Airport being key national
infrastructure, the return period of rain-
fall events was set at 1 in 100 year, higher
than most other areas in Singapore.
This is in accordance with the local PUB
Code of Practice on Surface Water Drainage,12
with Figure 4 showing the applica-
ble intensity-duration-frequency (IDF)
curve. Scenarios were then developed to
test the sensitivity of Changi Airport’s
infrastructure to the input parameters, as
can be seen in full in Table 2.
The other main input parameter was
the airport-specific physical environment
on which to project the specific sce-
narios. The key physical environment
parameters of interest are the terrain
levels and main drainage network, as
these determine the capacity to protect
against floods and convey storm water
out of the airport.
IMPACT ON CRITICAL ASSETS AND
OPERATION
To determine which of the airport assets
are potentially vulnerable to the pro-
jected climate change, such as sea-level
Figure 4 Applicable intensity-duration-frequency curve from the Public Utilities Board’s code of practice
Table 2 Climate change scenarios used as input to the study
Climate vector Today
(reference case)
2030 (short term)
2050 (medium term)
2100 (long term)
Rainfall Assess impact of current rainfall intensity. Assess impact of increased rainfall intensity.
Sea-level rise (SLR)
and storm surge
Assess impact of current tidal and storm-
surge level.
Assess impact of SLR, tidal and storm-surge
level.
Combined Assess combined impact of current tidal and
storm-surge level with rainfall intensity.
Assess combined impact of SLR, tidal and storm-
surge levels with increased rainfall intensity.

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rise and increase of rainfall intensities,
the physical effects of the projected cli-
mate change were modelled and assessed.
In combination with the outcomes of
the benchmarking study, we are now
able to define pathways for a course of
action at the airport — whether that is
installing flood barriers around certain
critical infrastructure on airside or taking
a more holistic approach to protect the
airport and the wider region by upgrad-
ing flood protection along the nearby
coast.
A targeted approach was adopted,
whereby the flood risk brought about
by increased rainfall intensity and sea-
level rise was assessed specifically for
critical assets. These critical assets were
identified based on the US Federal Avi-
ation Administration (FAA) definition
in the Airport Cooperative Research
Program13 Report 147 Climate Change
Adaptation Planning: Risk Assessment
for Airports: ‘Loss of the asset would
significantly impair or shut down the air-
port until repair, replacement, etc. were
s ec u r ed ’.
An inventory of critical assets at
Changi Airport was developed, includ-
ing navigational aids, runways and
taxiways; passenger terminals and the
control tower. More examples may be
found in Table 3.
TESTING ADAPTATION MEASURES
Adaptation measures were tested based
on the following analyses:
● A range of rainfall events and sea-
level-rise scenarios with timeframes
and key figures (such as the return
period of climate events) as agreed at a
multiagency level
● Accurate terrain levels and on-site
main drainage network/infrastructure
obtained through aerial mapping and
as-built plans and supplemented with
site visits
Table 3 Sample of critical assets at Changi Airport that were studied for ood risk due to the climate change
effects of increased rainfall intensity and sea-level rise
Type Assets
Airside infrastructure • Changi runways and taxiways
• Navigational aids, surveillance and communication
• Aprons
• Rescue and re-ghting stations
Landside infrastructure • Changi terminals 1–4
• Airport boulevard
• Air trafc control tower
• Utility infrastructure
Changi airfreight centre facilities • Fuel farm
• Air freight and cargo buildings
• Maintenance, repair and overhaul (MRO) hangars
Figure 5 Example of vulnerable area with temporary pond-
ing risk due to the climate change effects of increased rainfall
intensity and sea-level rise

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● Detailed inventory of critical assets to
enable a targeted airport-wide review
of the flood risk.
Based on the study methodology
described, the flood risk analysis indicates
certain vulnerable areas and assets. Figure
5 shows an example of a vulnerable area
with temporary ponding risk: part of the
runway before works under the Changi
East development, in which adjustments
were implemented to prevent flooding.
Yet this spells the need for adaptation
measures to protect affected areas and
assets in ensuring the continued proper
functioning of the equipment within.
Adaptation measures would need to
cover flood protection for vulnerable
asset(s) and allow for enough drainage
capacity to cater for any projected increase
in rainfall intensity. First, asset flood pro-
tection can broadly be classified into two
categories:
1. Local measures that protect individual
assets rather than an entire area —
these include fixed flood barriers such
as low walls around the specific asset
(Figure 6).
2. Perimeter/district-level protection of
an area rather than individual assets —
such a protection system could con-
sist of levees/tidal gates for protection
against sea-level rise and detention
ponds/pumping stations to manage
rainfall runoff (Figure 7).
In the near term, critical assets that are
vulnerable would have to be protected.
As these are relatively small in number,
it would make sense to implement local
measures to ensure immediate protection
(ie fixed flood barriers).
In the medium to long term, how-
ever, a greater extent of the airport and
more critical assets will be at risk as
the effects of climate change intensify.
Hence, there is merit to adopt a more
holistic system of protection around the
airport perimeter/at a larger district level
extending beyond the airport rather
than implementing local measures to
protect individual assets. District-level
protection has the benefit of being
comprehensive, allowing greater flex-
ibility in the future development of
airport facilities and being more robust
Figure 6 Illustration of a xed ood barrier local measure protecting an individual critical asset
Figure 7 Schematic diagram of a perimeter/district-level
protection system

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considering unforeseen asset interde-
pendencies. Furthermore, district-level
protection may be more cost effective
in the long run. Such a wider protec-
tion system is already successfully in
place at several international airports
of similar capacity and characteristics
to Changi Airport, such as Bangkok
Suvarnabhumi Airport or Incheon Inter-
national Airport.
Adopting such a system will enable
Changi Airport’s own efforts to dove-
tail with initiatives by other government
agencies. In 2016, a 1 kilometre stretch of
Nicoll Drive, which follows the shoreline
near Changi Beach and is just outside the
airport boundar y fence, was raised 0.8
metres by the Land Transport Author-
ity (LTA). The resultant raised road level
effectively acts as a levee to protect the
land behind it, including Changi Airport
and can potentially join up with future
tidal gates in the airport’s main drains to
form a seamless line of coastal defence
against sea-level rise.
Secondly, even as local measures and
perimeter/district-level protection are
implemented in the near and medium to
long term, respectively, drainage capac-
ity must be maintained to convey storm
water out of Changi Airport. To achieve
this, drainage network review and nec-
essary upgrading must be an ongoing
process.
ADAPTATION PATHWAY TOWARDS A
CLIMATE RESILIENT CHANGI AIRPORT
Preparing Singapore Changi Airport to
stay resilient to climate change will be
a long-term endeavour. A whole-of-
government approach including contin-
uous alignment with various authorities
on boundary conditions, results and
pathways has resulted in a shared effort
to achieve climate change resilience for
Changi Airport. A long term, incre-
mental and flexible adaptation pathway
for Changi Airport has been formulated
(Figure 8).
Figure 8 Climate change adaptation pathway for Changi Airport

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The adoption of a long-term, incre-
mental and flexible adaptation pathway
for Changi Airport heeds ICAO’s
caution on climate change affecting
airports, including the effects of
increased rainfall intensity and rising sea
levels and underlines CAAS’s and other
airport stakeholders’ commitment to
ensure the continued safety and smooth
travel of passengers through Changi
Airport.
As there is uncertainty as to the rate
and eventual extent of climate change,
there is merit in adopting a pathway
that can be implemented incremen-
tally. For instance, extending the useful
life of a fixed flood barrier local mea-
sure by increasing its height as needed,
yet being flexible enough to transition
into a perimeter/district-level protection
system in the future. All the while, the
pathway must be underpinned by suffi-
cient drainage capacity.
CONCLUSIONS AND DISCUSSION
Urban areas around the world have been
developing measures relating to water
crises, climate change and urbanisation,
but there has not been decisive progress
with implementation, as evidenced by
various recent examples of major airport
flooding. Because of their important
roles in national development, their rel-
evance for disaster response efforts and
their potential in taking the lead, major
airports can be ambassadors in making
urban areas more climate resilient. One
of the frontrunners in seizing the oppor-
tunity to implement CRA planning is
Singapore Changi Airport, the world’s
best airport.
The comprehensive climate change
study for Changi Airport delivers a long-
term, incremental and flexible adaptation
pathway, protecting airport infrastructure
from the effects of an increase in max-
imum rainfall intensity, sea-level rise
and storm surges through whole-of-
government, district-level measures. The
extreme event scenarios formulated with
Changi Airport ensure that the protec-
tion of the identified critical assets is in
line with the risk appetite and vision
defined by the Resilience Working
Group as carefully coordinated for the
whole of Singapore.
While focussing on the first two
constructive ambitions of the CR A
framework,14 a CRA is not just about
protecting infrastructure and its oper-
ation from flooding and extreme
weather events. It is also about enabling
airports to become more sustainable
and improve local climate and energy
management — something that airports
are going to have to embrace if they
are to sur vive.
Airports have large water footprints
that can be reduced through innovative
technology and practices, providing a role
model on water conservation not only
for the local community but the nation
as a whole. The adaptation pathway for
Changi Airport offers the opportunity to
upscale its ambitions with the progressive
reduction of water use via a multitargeted
approach across the airport. Changi Air-
port might be considered as a rainwater
collector in addition to Singapore’s
national tap and claim its leadership in
water management with a dedicated
campaign to reduce water use across the
airport and educate other water users —
across the globe — in how to better use
scarce water resources.
ACKNOWLEDGMENTS
The authors would like to thank CAAS
for providing permission to use selected
content and relevant illustrations of the

Dolman anD Vorage
66 © HENRY STEWART PUBLICATIONS 1750-1938 JOURNAL OF AIRPORT MANAGEMENT VOL. 14, NO. 1, 54–66 WINTER 2019–20
2016 climate change study for Changi
Airport in this paper.
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