The document discusses the research project on controlled flooding in deltas, focusing on the socio-political drivers and potential contributions to delta resilience. Key trends in flood management include ecosystem-based approaches, long-term planning, and restoration of flood dynamics, with a case study of the Noordwaard polder demonstrating innovative hydraulic engineering. It emphasizes the complexity of deltas as social-ecological systems and proposes new conceptual frameworks for understanding flood resilience and sedimentation processes.

1. Controlled flooding in the delta
Martijn van Staveren
PhD candidate @ Environmental Policy Group, Wageningen University
Visiting researcher to Stockholm Environmental Institute, 2015
4-9-2015

2. Outline
 Why are we here & acknowledgements
 Introduction & objective of the presentation
 Into deltas – and trends in delta/flood management
 Topics for discussion
 Questions/discussion

3. Introduction: research project
 Funding: NWO, carried out by Wageningen UR, UNESCO-
IHE and partners working in the deltas
 Timeframe: 2012 – 2017 (0,8 fte)
 Domain: Environmental Policy
 Formal research objective: understanding socio-political
drivers of controlled flooding initiatives, and asses their
potential contribution to building delta resilience
 Personal fascination: the ‘place’ of floods in delta
histories and futures/(un)controlled flooding
 Approach: STS (Science and Technology Studies)/policy
 Objective: present work and have a discussion about
three themes

4. Into deltas: opportunities and
challenges
Flood
management
Urbanization
Various
interests
Climate
change
Institutional
complexity

5. (Dutch) hydraulic engineering

6. Four trends in delta/flood management
policy
1. Ecosystem-based approaches to water/floods
2. Interest in ‘long term delta planning’ in delta flood
management
3. Flood dynamics restoration emerges in several deltas
4. New conceptualizations of deltas (topic for discussion)
Diving into controlled flooding:
Understanding socio-political drivers of
these initiatives, and asses their potential
contribution to building delta resilience

7. Trend #1: Ecosystem-based approaches
to water/floods
 Concerns about environmental impact of engineering
 Driven by eco-’inspired’ engineers
 Mixed responses from ‘traditional’ engineering (+/-)
 Presented as innovation (but not always that new)

8. Trend #2: interest in ‘long term delta
planning’ in delta flood management
 Thinking in longer time scales (i.e. 100 years)
 To some extent parachuting Dutch delta planning
concepts in other context...
 Limited historical awareness (existing engineering
works/past plans)
 Who’s delta? Stakeholders, participation and decision-
making

9. Trend #3: Flood dynamics restoration
emerges in several deltas
 Restoring or preserving (tidal) flood dynamics
 Different drivers (e.g. top down ‘hydrocracy’ vs local
action)
 Social shaping of technology (design and ‘operations’)
 Place in and contribution to long term delta survival?

10. Case study example: de-poldering
Noordwaard polder
 Formulated under Room
for the River project
 Lowering northern
embankments to take in
water at a certain level
(ca once per 10 years)
 Water flows through grass
land towards the estuary
 Contributing to fresh
water wetlands
 Some families moved out
(compensated), other
stayed (houses on raised
mounds)
De-poldering the
Noordwaard in
the Dutch delta
A large part of the Noordwaard polder will be reconnected to
the adjacent river, to facilitate controlled flooding in times of
high river discharge, thereby lowering peak water levels.
Together with restored tidal dynamics, this contributes to the
Biesbosch wetlands. Dikes will be removed or lowered to
control flood water entering into the former agricultural area.
Innovative hybrid-engineered dike
Near the Steurgat Fortress, a willow forest will be laid out in
front of a section of the dike. This reduces flood waves and
compensates for required dike reinforcements.
Flow-through
zone
Intake
High water
level
DORDRECHT
National
Park de
Biesbosch
FIGURES
70km dikes
50km new roads
29 mounds
38 bridges
12 pumping stations
4 million m3 of earth
moving
WERKENDAM
Homes rebuilt
on mounds
Flow-through
zone
© Infographic: Loek Weijts Text: Martijn van Staveren

11. Topics for discussion
1. Conceptualizing deltas – as complex social-ecological
systems, in which interaction is mediated via hydraulic
engineering?
2. Dealing with flood management in deltas – e.g. a new
perspective on sedimentation processes?
3. Building long term delta resilience with controlled
flooding (and sedimentation)?

12. Trend #4 and discussion point #1: new
attempts to conceptualize/define deltas

13. Deltas systems/river basins
‘development’ over time
Linear?
Trajectories?
T-bana?

14. One type: deltas as social-ecological
systems
 Approach seems a good fit to environmental dynamics
and social responses (i.e. interaction) to them in deltas,
and brings in resilience thinking.
 But what about
● ... how this interaction actually takes shape in practice?
● ... the role of hydraulic engineering in shaping how deltas
evolve towards the future?
 (Conceptual) lessons can be learned from socio-technical
systems research, which has delivered several studies on
the hydraulic engineering works.

15. Socio-technical research on hydraulic
engineering
 Provides some ‘new’ concepts e.g.
● technological lock-in
● path dependency
● technological trajectories following technological (in this case
hydraulic) actions -> understanding the development of delta
by means of delta trajectories
● (eco-)technological add-ons which offer some flexibility in
hydraulic works’ operation or functioning
 Existing hydraulic works act as ‘system attractors’ ->
needs to be taken into account when talking about delta
futures
 Historically informed analyses of technological systems
 Provides a basis to identify unsustainable or undesirable
system trajectories (partly a political endeavour)

16. Path dependency (storm surge barrier)
 Oosterschelde storm surge
barrier: 2 billion euros
 Paradigm: promised to provide
flood protection ‘forever’
following a large scale flood
disaster in 1953
 Lifespan 200 years
 Despite sluice gates,
environmental consequences,
addressed as second order
effects since TINA
 Removal ‘out of the question’
(Province/Ministry/society)

17. Technological lock-in (embankments)
 Low embankments in the past (14th century)
 More attractive to heighten due to past investments and
earlier efforts, than to chose for other approaches. Also
‘mentally’.
 Century-long cycles of embankment heightening
 Difference river/land in some places up to 8 (!) meters

18. How to approach deltas (proposed)
 As social-ecological systems, in which interaction is
‘mediated’ via hydraulic engineering. Social-ecological-
technological system?
 Deltas develop over time dynamically, moving within a
range of relative ‘stability’ unless too little or too much
water tips the system towards another regime
 Flood dynamics and sedimentation processes are
inherent to a ‘stable’ delta system
 Managing for change via (eco-)technological add-ons
 Argued in Van Staveren and van Tatenhove (in review
with Ecology&Society, to be resubmitted Sept 2015)

19. Discussion point #2: a new
perspective on sedimentation
processes?
 In the Netherlands: controlled flooding in the
Noordwaard de-poldering indicate tight control of both
water flows and sediment processes
 In Bangladesh, tidal polders are filled up with sediment,
but not primarily to increase land height
 In other parts of the world (e.g. the Mekong delta coast,
Indonesia) mangroves are specifically planted to catch
floating sediment particles for coastal improvement
 Therefore, some indicative/associated developments, but
not spot-on -> your experiences?

20. Discussion point #3: flood/delta
resilience
 Many definitions, etc
 Rockström et al (2014)’s
interpretation of system’s
resilience:
1. Capacity to absorb
disturbances/shocks
2. (learning) adaptability to
stressors while maintaining
a certain system state
3. Transformability after
crossing threshold
 But...

21. Discussion point #3: flood/delta
resilience
 Distinction between water/flood/delta resilience
(resilience of delta inhabitants in the face of extreme
floods) and delta resilience (resilience of the social-
ecological delta in the face environmental (broader than
floods!) dynamics)
 Water resilience (control - state - driving variable)
 Flood resilience (society resilient in the face of extreme
floods – which doesn’t necessarily preventing all
floods). Short term small floods contribute to building
long term flood resilience?
 Delta resilience. Integrity of the social-ecological delta
system, in providing delta/ecosystem services to
humans.

22. Back to topics for discussion
1. Conceptualizing deltas – as complex social-ecological
systems, in which interaction is mediated via hydraulic
engineering?
2. Dealing with flood management in deltas – a new
perspective on sedimentation processes?
3. Building long term delta resilience (for humans and the
dynamic environmental of the delta) with controlled
flooding (and sedimentation)?

23. Thank you for your time & attention!
More information:
 www.wageningenur.nl/enp
 martijnvanstaveren.blogspot.nl
 Van Staveren M.F., Warner J.F., van Tatenhove J.P.M., Wester P. 2014.
Let’s bring in the floods. Controlled flooding as a strategy for long term
delta survival? Water International,
http://dx.doi.org/10.1080/02508060.2014.957510.
 Van Staveren M.F., van Tatenhove J.P.M. (in review with Ecology&Society,
to be resubmitted Sept 2015). Deltas as social-ecological systems and
the role of hydraulic engineering in (re-)shaping delta trajectories