G
oing against the flow of centuries
of experience with building
dikes is not easy. People put a
lot of trust in hard engineering
infrastructure. As a result,
introducing an innovative
concept to flood protection is
far from straightforward, but
current conditions seem to favour
'
building with nature'. Worldwide, people are migrating
to cities in coastal, delta and river areas. It is precisely
these areas that are most affected by climate change,
land subsidence and sea-level rise. So safety is a major
issue. It has to be reconciled with intensive demand for
sustainable and habitable places to live. Constantly
raising dikes is not an approach that can continue to
rely on automatic support, and we need to consider
alternative ways of improving flood protection.
Underestimated
These factors mean that people are now open to the
idea of, and even enthusiastic about, using natural
landscapes for flood protection. Even so, hard
infrastructure still dominates.
Bregje van Wesenbeeck, an ecologist specialising in
eco-engineering, explains why. ‘Eco-engineering has
a lot of benefits. It can cut construction costs, it takes
CO2 out of the atmosphere, it makes the surroundings
greener and generates extra revenue from things like
tourism or water treatment. Even though more and
more people throughout the world are starting to
understand the benefits and even though interest in the
role of ecosystems in flood protection is on the increase,
many people still underestimate the benefits that
the ecosystem can deliver. As a result, those benefits
are not included in the design process for hydraulic
infrastructure or in social cost-benefit analysis. In fact,
ALLIANCE OF ENGINEERS AND EC
‘
Building with nature’ generates
numerous benefits. Even so, hard
infrastructure still dominates flood
protection. Why? And how can we
get away from this reflex approach?
BY CARMEN BOERSMA
PHOTO: SAM RENTMEESTER
nature is often destroyed without thinking about the
role it can play in the design.’
Rich dike
To get out of this conundrum, Bregje van Wesenbeeck
thinks eco-engineering should be part of the design
process and that engineers and ecologists should work
together more. ‘Ecologists should be involved from the
very outset of the design process for water engineering
projects,’ she argues. ‘Eco-engineering is, generally
speaking, an option in all circumstances: urban or non-
urban settings, large or small spaces. Even in urban
areas where only hard solutions are possible, ecological
options are feasible. Take the "rich dike" approach, in
which the foot of the dike is shaped so that vegetation
can grow on it.’
DOSSIER BUILDING WITH NATURE
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