Good practice in risk analysis

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EDITORIAL
Good practice in risk analysis
This edition of the journal comprises papers presented at
the Fouth FLOODrisk Conference. The conference was
originally scheduled to be held in Budapest in June 2020.
The worldwide coronavirus pandemic emerged in late
2019 and early 2020, and by the time the conference was
due to take place, many countries were in ‘lockdown’,
causing the postponement of the conference.
The pandemic is a worldwide tragedy with millions of
lives lost. In response to this threat to humanity, science
was thrust to the forefront, both in terms of advice to gov-
ernments on how to restrict the spread and also the
remarkable speed of development and implementation of
the vaccines.
Previous editorials in the Journal of Flood Risk Man-
agement (De Bruijn, 2020; Montz, 2020; Priest, 2021) have
highlighted parallels between the management of the
pandemic and flooding and the resilience of communities
and their natural ability to adapt and overcome adversity.
Desk-based workers all over the world quickly adapted to
virtual meetings. Although this process was not without
obstacles. Who could not sympathise with, and admire
the professionalism of, the US lawyer who, struggling
with image filters on a video call, felt obliged to declare
that he was not a cat? There will be very few readers who
have not directly contributed to the rise of ‘you are on
mute’to the top of the most used phrases charts
(Knorr & Schreml, 2021)! Nevertheless, so quick was the
adaptation process, that this conference eventually took
place in a virtual online format in June 2021. Something
that would not have been considered viable pre-
pandemic had become ‘the norm’within the space of
a year.
There are of course ‘lessons to be learned’from the
pandemic that translates to all aspects of risk analysis
and management. It is interesting to note the risk assess-
ment process adopted by some countries has been
deemed deficient (Lacobucci, 2021). The deficiency iden-
tified relates to a need to plan for a range of challenging
scenarios that have not happened in the past, as well as
those that have.
It is well-known the risk analysis process requires
consideration of the likelihood and impact of all hazard-
ous events (e.g., Bedford & Cooke, 2001). There is no
option to ignore events that are complex to characterise
and evaluate. It is also a well-known pitfall there can be
a tendency to rely solely on historical evidence, or arche-
typal design events, when defining hazardous events
(HSE, 2003).
In this regard, it is perhaps surprising, that the well-
established approach to representing the failure of flood
defence infrastructure, using probability distributions
known as fragility curves (e.g., Apel et al., 2004;Ayyub
et al., 2009; Schultz et al., 2010;Simm&Tarrant,2018;
USACE, 1996; Vorogushyn et al., 2010)aspartoftherisk
analysis process, is not universally implemented. Many
flooding studies still rely on methods that have, as a prereq-
uisite, an assumption that flood defences and related infra-
structure cannot fail. With a long legacy of ageing flood
defence infrastructure in many countries and an expected
increase in the frequency of extreme events as a result of
climate change (e.g., Kay et al., 2011; Schaller et al., 2016),
widespread adoption of best practice in risk analysis, within
the context of flood risk analysis, would seem prudent.
1|THIS SPECIAL ISSUE
Since climate change and socio-economic development
will increase flood risk, in the absence of future mitiga-
tion measures, it is routine to incorporate these aspects
into the decision making process. There is, however,
much to learn with regard to capturing the complexities
and associated uncertainties in this process. This issue
makes a substantial contribution in this regard.
Sea-level rise will increase flood risk globally.
Tiggeloven et al. (2022), explore, for the first time on a
global scale, the potential for natural flood management
measures to support the mitigation of these impacts. The
impact of foreshore vegetation, in terms of risk reduction
in the present day, is evaluated. The future impact, if the
DOI: 10.1111/jfr3.12824
This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided
the original work is properly cited.
© 2022 The Authors. Journal of Flood Risk Management published by Chartered Institution of Water and Environmental Management and John Wiley & Sons Ltd.
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https://doi.org/10.1111/jfr3.12824

vegetation is conserved, is then evaluated under different
climate change scenarios, with a significant benefit
demonstrated.
Also relating to sea-level rise, De Bruijn et al. (2022)
consider adaptation options for the Rhine-Meuse Delta in
the Netherlands. A closed, pumped, system is contrasted
with an open channel diversion option. The latter is
shown to be able to accommodate a greater range of
potential range of sea-level rise. Given the uncertainties,
this attribute of flexibility is often a vital aspect of adapta-
tion decision making. Groeneweg et al. (2022) consider
scenarios of climate changes on the wind climate.
Through impacts on wave conditions (height and direc-
tion) and set-up of water levels, a first estimate is given of
the effect of uncertainties in storminess on Dutch levee
design. The social response is another critical component
of adaptation. Dillenardt et al. (2021), use socio-
psychological models of adaptive behaviour to explore
the actions of different demographics in response to plu-
vial flood events in Germany.
Allowances for future climate change are routinely
made in flood risk analyses. When de-trending historical
data it is, however, complex to distinguish whether
observed trends relate to changes in land use, natural
variability or climate change. Griffin et al. (2022), explore
these aspects of observed non-stationarity with a view to
refining standard climate change allowances on peak
river flows.
Understanding present-day risk is of course the cor-
nerstone of the robust assessment of climate change-
related impacts. Observations and data gathering of
floods that have occurred, and successful numerical
model simulations of past events, are crucial elements in
this process. Cohen et al. (2021) explore and compare dif-
ferent sources of remote observation techniques relating
to fluvial flooding in Finland. Provan et al. (2022)
describe the successful calibration of a regional storm
surge model in Canada. It is envisaged this regional
model will be further developed to help support future,
climate change-related, analyses.
We hope this issue challenges researchers and practi-
tioners, working in the field of flood risk management, to
reflect on their methods and provides helpful insights for
the further development of a climate-robust and sustain-
able society.
Ben Gouldby
1
Karin de Bruijn
2
1
HR Wallingford, Flood Management, Wallingford,
Oxfordshire, UK
2
Flood Risk Management, Deltares, Delft, Netherlands
Correspondence
Ben Gouldby, HR Wallingford, Flood Management,
Wallingford, Oxfordshire, UK.
Email: b.gouldby@hrwallingford.com
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