The term “Acqua Alta” used to be employed when talking about the high tides that affected Venice seasonally. Today, the permanent threat of rising sea levels remains imminent, which has caused cities all over the world to carry out resilience practices.
Venice, iconic for its use of canals instead of streets, is the city representing those which are vulnerable to the effects of climate change. This kind of environmental phenomenon affects two thirds of the largest cities in the world, known as “delta cities” (New York, Rotterdam, Amsterdam, among others).
The rising sea level is estimated to be between 50 and 100 centimeters by year 2100, reason why the design approach for these areas lies in adjustment models and hydraulic infrastructure solutions, which allow for their subsistence. The options ranging from pumping systems to wetland protection are initiatives being applied with the purpose of having more resilient cities.
The following three examples include the design ideology that seeks to integrate climate change to the plans for vulnerable cities.
Rotterdam, Holland
Skimping on solutions is not an option in Holland, at least one fourth of the territory is located below sea level. Even though this is alarming information, the ideology has been to take change as an opportunity to make improvements.
In essence, it is about letting water in, wherever possible, and don’t expect to tame Mother Nature: it is about coexisting with water, rather than fight to defeat it. -Michael Kimmelman, NYT
Rotterdam is an adjustment study case for the implementation of programs in the three intervention categories. The Maeslant Barrier is a floodgate that protects the city from its connection with the North Sea, preventing it from passing in case of storm. Equally, the city is part of a program for increasing biodiversity and its active integration to society.
Venice, Italy
Historic records of Venice floods show that a protection system is a much needed measure, both for heritage and human defense. The MOSE Project (Modulo Spermimentale Elettromeccanico) is a 78-floodgate system distributed in different spots, these are activated when the tide exceeds 1.10 meters of the average sea level. It was developed in 2003 and due to corruption matters it has not been finished. The functionality crisis suffered by the city with each flood has made the need to prevent and implement adjustment plans evident.
New Orleans, United States
Environmental systems like wetlands and mangroves are the first defense line when a climatic phenomenon threatens the coasts, their preservation and restoration is one of the most promoted projects in the city of New Orleans (United States). Hurricane Katrina in 2005 proved that pumping systems are not enough to prevent floods, and for this reason, greater attention was directed towards wetlands, for their ability to retain water. One study showed that the ecosystems that protect the East coast prevented 625 million dollars in damages by absorbing the impact of Hurricane Sandy in 2012.
References
Robert Muggah. The world’s coastal cities are going under. Here’s how some are fighting back.World Economic Forum. 16 Jan 2019.
C40 Cities Climate Leadership Group. Climate Change Adaptation in Delta Cities. Febrero 2016
Beck, Michael. Narayan, Siddharth. Coastal Cities Need to Love Their Wetlands. CityLab. Septiembre 2017.
Kimmelman, Michael. The Dutch Have Solutions to Rising Seas. The World Is Watching. New York Times. Junio 2017.