Afloat : a new ground for water management policies : the artificial nature of the city
Giulia Milanesi
Afloat : a new ground for water management policies : the artificial nature of the city.
Rel. Francesca Frassoldati, Gustavo Ambrosini, Mauro Berta. Politecnico di Torino, Corso di laurea magistrale in Architettura Costruzione Città, 2017
Abstract
INTRODUCTION
Currently, the average global flood losses are estimated to be a billion of dollars/billions of dollars per year. The country incurring the heaviest losses is China, followed by the USA and India. The good news is that the death toll of floods in China has been steadily declining thanks to government actions, like the construction of dams, dikes and levees. The bad news is that the economic costs of floods are steadily increasing and they are likely to increase in the foreseeable future.
Each year flooding events cost to China dozens of casualties and more than 6 billion US dollars to reconstruct buildings and infrastructure after the disaster. (2016 Annual Global Climate and Catastrophe Report).
Global natural disasters in 2016 combined to cause economic losses of USD 210 billion [...]. The economic losses were attributed to 315 separate events [...]. Notable events during the year included major earthquakes in Japan; Hurricane Matthew in the United States and Caribbean; catastrophic summer flooding in China. Europe, and the United States."
(Annual Global Climate and Catastrophe Report. 2016)
This awareness is increasing the demand for better information to recognize how and where this water risk could occur and how to reduce it. Preventing floods is not just a way to save money, but also a way to maintain a high quality of life in Chinese cities and to decrease the risk of death and injury.
In the last three months only, several countries have been affected by flooding events. Texas with hurricane Harvey is the most recent one, but before that Nepal with its 500 victims, Sierra Leone with 16 million inhabitants affected by the flooding, southern and central China with the massive floods occurred in July, which caused 22 victims and 11 million people in danger, Paris hit by the heaviest storm since 1880, and then again China and Shenzhen with the typhoon floods happened some weeks ago. These are just some examples that help us to outline how much water related disasters are becoming increasingly common and dangerous. (http://floodlist.com/).
The starting scenario of Qianhai bay displays a situation created on the base of today’s data and more conservative previsions made without taking into account possible future disasters and using data prepared for the initial de sign competition dated 2010, forecast already no loger accurated. In fact, the James Corner Field Operation’s masterplan could work during the worst expected water related scenario, but it does not consider what could happen if that scenario would become the average condition, in case further floods would occur, in case of further floods and injuries. The bay has been created with a fast and not totally organized process of land reclamation that has changed the environment and its dynamic.
The floodplain behind the 15-square kilometers of coastline is home to approximately 300000 people. This area will contain some of the central future hubs that will economically connect Shenzhen with Hong Kong and the rest of the world. The area contains also houses which help to increase the value of the land. In case floods would occur in the area occasionally or repeatedly on a yearly basis, with no adequate countermeasures, the land and property value would decrease rapidly. As a consequence, selling the new district as an improved commercial zone with less limitation than the rest of China would be unsuccessful. Furthermore, we should also consider the aftermath of the flood. Mould and mud, for example, are going to be an important issue for all the buildings now completely safe. After the recent hurricane Harvey in Texas, for example, many houses started being affected by the mould problem, which causes lung infections, cold, sore throat and asthma attacks as well. Many people are leaving their houses for dryer accommodation, leaving behind places where no one could live without big cleaning interventions. In fact, if you don’t dry the flooded area thoroughly within 24 to 48 hours, mould will start to form. Additionally, rebuilding after a flooding will cost to the city more than the capital invested initially to construct the area.
Flooding events are caused, among other causes, by global warming and heavy rain period. Global warming is getting worse year after year and it is totally irreversible. Heavy rains are normal in areas like Shenzhen, where they happen several times in a year. The techical approches related to flooding are focused on river line and sea floods, although pluvial flood caused by heavy rains constitutes a major danger for a lot of cities around the world. The difference between the riverine or sea flood and the pluvial one is related to temporality and spatiality. The first one is happening little by little, year after year, the second one is local and punctual in time. The first one affects costal area, the second one local spots in the city where the drainage system is not able to discharge all the water. A good design proposal would be able to face both situations, the one caused by a change in the global temperature and the one related to rain (Sorensen, J., Persson, A., Stemudd, C., Aspegren, H., Nilsson, J., Nordstrom, J., Mobini, S.,2016).The concept was the product of a re¬search phase in which we studied the history of resilience planning in the Qianhai bay and how the James Comer Fields Operation masterplan will answer to water level changing. The research demonstrated that resilience plans have typically considered the existing city, failing in providing an answer for the natural growth and transformation of land and ocean throughout the years.
The solution was to provides punctual landscape design proposals to encourage a different relation with a changeable environment and create a design that could help the district to face the emergency with a higher tolerance.
We cannot quantify specifically the amount of water that will be present in the area in the future, but we can try to stress today’s situation using data coming from prevision maps and flood occurrence analysis (as Aqueduct maps and previsions maps presented in the common book).
The new landscape with the linear green and blue channel has many advantages. It creates possibilities for integrating the commercial plans with the uncertain landscape, it makes possible to create social areas and gathering places for communities and it helps to transform the resilience program into a social and environmental integrated design. As a dynamic process, moreover, it enables planners to adapt to emergent developments, such as global climate change and new legislation. In addition, it creates a water landscape exploitable in every water and climate situation. The aquatic landscape is not just a static, neutral and safe scenario, but something changeable and not normally accessible. It is sufficient to think of the Italian situation, where rivers and canals are mostly closed and inaccessible. Trying to rethink an aquatic landscape means also trying to keep it accessible in every situation and to adequate functions to different water related events.
"Flooding it’s not new to the United States, and it's not new to a lot of places in the world. But we lost track of that knowledge. And now with challenges like climate change, we are forced to un-forget that; to remember better and to start building new approaches based on that memory. And of course we will do better than we did before. Henk Ovink talking about New York City initiative"
(Nate Berg. 2017)
To better understand what kind of tools are necessary to design a resilient landscape, we can quote the ten points used by the jury of the “Rebuild by design” competition in New York. After Hurricane Sandy impacted on 13 states, costing more than $65 billions in damages and economic loss, President Obama’s Hurricane Sandy Rebuilding Task Force launched an innovative design competition, Rebuild by Design, that coupled innovation and global expertise with community in order to develop implementable solutions to the region’s most complex needs. In partnership with U.S. Housing and Urban Development (HUD), Municipal
Art Society, Regional Plan Association, NYU’s Institute for Public Knowledge, The Van Alen Institute, and with the support from The Rockefeller Foundation and other philanthropic partners, the multi-stage competition guided participants through in-depth research, cross-sector, cross-professional collaboration, and iterative design. Participants collaborated with community and local government stakeholders to ensure each stage of the competition was based on the best knowledge and talent and that final proposals were realistic and replicable. The jury chose the winning proposal following ten points:
The jury choose the winning proposal following ten points:
1 design for and encourage projects that provide multiple benefits;
2 achieving comprehensive resilience will require a long-term approach;
3 align multiple streams of funding & administrative requirements;
4 create more flexibility in disaster recovery;
5 identify additional funding sources to support long-term monitoring and maintenance;
6 use lessons learned from project implementation to reform permitting;
7 encourage coordination across agencies and levels of government;
8 in addition to infrastructure projects, pursue legal and policy mechanisms;
9 encourage robust public engagement and partnerships;
10 encourage better pre-disaster planning and mitigation.
The Rebuild by Design Hurricane Sandy Design Competition changed the way the federal government responds to disaster and it became the model now used in other regions to prepare communities for future uncertainties. Its success has also inspired other efforts. In 2014, President Obama launched the National Disaster Resilience Competition, which awarded $1 billion to 13 cities and states across the country to fund resilience-building projects. Internationally, The Rockefeller Foundation, in partnership with the USAID and The Swedish International Development Agency, the competition model’s success also led to the formation of the Rebuild by Design organization, which is helping cities and communities around the globe to become more resilient through collaborative research and design.
In general, in flooding situations we should use three strategies: resist, defend, store and reuse. Resist to water attack trying to implement architecture (ex. move buildings to higher elevations, create boundaries for water), defend to create safe areas, store to collect water for public functions and, finally, reuse to find the value of a disaster event. (Oma, 2012)
In addition, we should work with the users to encourage the idea of changeable landscape where water could be present in a moment The should be used to see the park with and without water without being worried about the inundation.
In conclusion, the question that we are trying to answer is if a new water awareness is becoming “the new normal” and if water related policy could become a territorial praxis, which could bring prosperity to the landscape in a social and morphological way, using what is existing in the urban landscape as something that is necessary and positive for us. To answer that question I will use specific litterature and report about global warming and flood management. All the documents I took in account assume the problem of global warming as real and tries to answer to a possible environmental change. I will not question in this paper what it could change if global warming effects are overstimated in intensity and time, however it could be an interesting future work critically analyze this thesis work taking in account also a totally opposed opinion.
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