Protecting cities from floods by bringing flood control tunnels into service to regulate flows...
INTERVIEW WITH… SØREN DEGN ESKESEN FORMER PRESIDENT OF ITA-AITES (2013-2016): “UNDERGROUND SPACE CAN CONTRIBUTE TO REDUCING THE CARBON FOOTPRINT AND PROTECT CITIES FROM FLOODS.”
The effects of climate change can be felt throughout the world, with repeated, increasingly frequent river floods and marine submersions. In the face of these phenomena, which endanger both populations and structures, what solutions can underground infrastructures provide?
Søren Degn ESKESEN: Cities around the world must deal with the challenge of rapid urbanization
and climate change. At ITA we are convinced that underground space in urban areas can be used
for meeting the many challenges cities face today. If done at an early stage and in an organized manner, the development of underground space can contribute to the sustainable development of
urban areas, including to help them adapt to the effects of climate change. The solutions fall into
two categories.
First of all, exploiting underground spaces can contribute to the reduction of the carbon footprint generated by big cities. Several options are open in this framework. The first consists in developing an underground transport system that uses renewable energy, like the subway that runs on non-carbon energy. Another possibility could be to produce energy based on green resources such as water. Indeed, when it comes to hydroelectricity, it is essential to make use of underground spaces by building tunnels for water conveyance and underground storage spaces for electric power stations.
The occupation of underground space could also offer the possibility of protecting cities from floods by bringing flood control tunnels into service to regulate flows. The principle consists in diverting water through these tunnels to prevent potential overflow on the surface, or creating underground
infrastructures to retain water in periods of flooding. Such solutions have been used in several cities such as Buenos Aires in Argentina
Are governments becoming aware of the potential of underground infrastructures to protect populations and buildings? Is there a new awareness on the part of the international community about the subject?
Søren Degn ESKESEN: ITA has been reaching out to decision makers and urban planners for several years to convince them of the relevance of exploiting underground spaces. During our annual tunnel conferences held over the period 2011 to 2013 in Helsinki, Bangkok and Geneva, we organized open sessions where the subject was the use of underground space in a changing world. Cities everywhere are under pressure to deal with population growth and meet their future energy and transportation needs, using far more sustainable methods in order to reduce their carbon footprint and mitigate the effect of climate change. Decision makers and organizations are now talking about underground space and considering how to include the underground when building cities to make them more resilient. The ITA community supports them in their approach. The association has established its reputation and is invited to participate in working groups registered in the United Nations agenda.
ITA was named as one of the partners in the Expert Group on urban drainage set up by UN Habitat.
An excellent example of this is the SMART project in Kuala Lumpur.
UN Habitat recently identified 5 basic principles concerning urban drainage. One of them stipulates that ”effective use of tunnels and underground spaces is appropriate when conditions so require.” Tunnelling and underground space are now becoming an integral part of UN policy. So yes, the international community is aware of this issue. This is only a first stage, but it is a step forward which shows that ITA’s efforts are bearing fruit.
Did the New York Climate Summit in September 2014 enable ITA, which took part in it, to raise government representatives’ awareness of the solutions put forward for limiting the effects of weather disturbances?
Søren Degn ESKESEN: ITA was represented by the Chair of our Committee on Underground Space Han Admiraal and myself at the UN Climate Summit in New York in September 2014. At this historic meeting many governments and organizations pledged their alliance in combatting climate change.
From that moment on, it became clear that investors were increasingly backing green projects geared towards reducing carbon emissions. This is caused by three reasons outlined by the speakers.
Firstly there is no longer any doubt as to the fact that climate change is wreaking havoc with the environment and that it is caused by human activity. Moreover, the cost of not doing anything about
climate change now outweighs the cost of taking steps to curb it. Lastly, governments alone cannot change anything; the involvement of the private sector is vital.
This commitment must be the collective action of businesses that want to act together on the basis of common interests rather than the fruit of an individual initiative. Companies should be driven by a simple credo: if we don’t act now, there will soon be no planet left.
In the closing session UN Secretary General Ban Ki-Moon announced the introduction of a Global Geothermal Alliance in the field of Energy, which clearly shows that ITA's efforts in planned development of underground space must continue. Other important fields that ITA must remain focused on are the transportation sector and urbanization. These two sectors will play a vital role in implementing a low-carbon economy. The participants in the UN conference on the climate agreed that underground space is a relevant response to numerous urban challenges, thereby acknowledging ITA’s expertise as a global leader in the field of tunnelling and underground space.
How and with what kind of scientific and technical arguments can your industry encourage States to invest in underground infrastructures to limit the devastating effects of flooding and submergence which we know will get more frequent and more severe in the coming decades?
Søren Degn ESKESEN: Our industry has solutions for controlling floods by diverting water into tunnels to prevent water from rising to the surface. By launching a certain number of projects, we
have proven that solutions already exist. The message that must be conveyed is that it is cheaper,
safer and more efficient to propose solutions at an early stage to prevent disasters from occurring.
We need to convince states and government to invest in order to avert catastrophes.
The capital is better spent on investment for disaster risk reduction than on rebuilding cities after a disaster such as a flood.
Cities everywhere are under pressure to deal with population growth and meet their future energy and transportation needs. There are methods that are far more sustainable for reducing the carbon footprint and mitigating the effect of climate change.
Ensuring that populations can move around efficiently is critical to the quality of life and economic success of cities. Success depends on how cities utilize their underground, because what happens below the ground strongly influences what it is possible to achieve above ground. By investing in the underground you create room at the surface to develop the city into an economic powerhouse.
Currently, are there any significant ongoing construction sites in the world aiming at reinforcing the safety of populations and property located in flood-prone areas? If so, what are they?
Søren Degn ESKESEN: South East Asia is probably the area of the world with the greatest risk of flooding. In the Indonesian capital of Jakarta, flooding occurs too often. Several projects have been launched to cope with immediate remediation such as the tunnel that will connect the Ciliwung River in Bidaracina with the East Flood Canal in Eastern Jakarta. But the most important long-term project is the multi-purpose tunnel in Jakarta, based on the example of the Kuala Lumpur SMART
tunnel.
After the huge flood that occurred in Bangkok during autumn 2011, the Bangkok Metropolitan Administration (BMA) as well as the ITA members in Thailand (TUTG) came up with various solutions including tunnels to prevent such flooding. TUTG suggested constructing a long multi-purpose tunnel running from north of the capital city to the sea, and BMA is reinforcing its network of drainage tunnels. The construction of the tunnel began a few months ago. The tunnel will measure 6.4 km in length and 5 m in diameter.
Other projects exist in various countries and parts of the world. Even in my hometown Copenhagen, the capital of Denmark, we are considering building a tunnel that will serve as both a drainage tunnel and a sixlane road. At the moment there is a heavily congested road on the surface that follows the alignment of a river, which now flows in the drainage pipes. By making the road an underground artery and combining it with the function of a drainage tunnel that will serve to channel large amounts of falling water, we will free up surface space and put the river back in its original bed. We will create a recreational area nearby for the city’s inhabitants to enjoy.
Bangkok:How a 100 km long floodway beneath the eastern part of the city would work
Beyond large-scale structures built underground, in particular for transport, installations on a more modest scale may be set up in cities. Which of them is the most likely to be rolled out in European cities?
Søren Degn Eskesen: In addition to underground facilities related to the supply, storage and conveyance of water, those most commonly used in our cities, we are observing a new trend these
days: urban construction of underground infrastructures dedicated to the control and drainage of the volume of water. We have already noted that a certain number of projects related to these facilities have been launched and initiated by many cities, including Copenhagen. There, more than 100 projects are about to be put in place for the purpose of coping with torrential rains and floods.
This modest example can be applied to many cities in the world. That is why we urgently need to
act now and think about how underground space can be one of the solutions that should be envisaged, if we want to protect our urban heritage from the impacts generated by climate disruption.
A few months ago, Paris hosted the COP21, the World Climate Change Conference. During this event, climate disruption was once again at the heart of the debates. What were the key messages ITAAITES conveyed at the summit?
Søren Degn Eskesen: In our work with UN Habitat we have emphasized the role underground space can play in urban drainage and disaster risk reduction. We are now part of a process that consists in bringing cities and private partners closer together to launch projects that will achieve these goals.
The idea is to give up concepts and theories and concentrate on concrete action, especially in those fastgrowing cities that need such infrastructures but have never even considered the issue. We are challenged to come up with solutions to solve the problems these cities face, especially problems of drainage and channeling flows.
The advantages gained from the decisions about human management that we take today will be evaluated fairly by future generations the same way we measure the benefits of investments that our grandparents began. Such as the construction of the subway, or underground, in cities like Paris, London and New York.
Today’s city dwellers are still benefitting in their daily life from the investments made more than 100 years ago. ITA has never been so close to its goal: to attract the world’s attention and make sure tunnels and underground space are considered vital solutions to the greatest challenges our planet has ever faced. We are deeply committed to this goal and ITA will continue to proactively propose and implement solutions to these challenges.
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