Alexandria, Cleopatra’s birthplace, is facing a significant rise in building collapses due to coastal erosion and rising sea levels, increasing from one to forty annually over the past decade. Recent research highlights the city’s vulnerability, with approximately 7,000 structures at risk. Proposed solutions include constructing sand dunes and vegetation barriers to counteract seawater intrusion, with implications for similar coastal cities globally.
The city of Alexandria, renowned as the birthplace of Cleopatra, is witnessing a significant increase in building collapses attributed to coastal erosion and rising sea levels. Recent research conducted by the University of Southern California indicates that the annual collapse rate has escalated from approximately one to 40 buildings over the past decade, primarily due to seawater encroaching below urban foundations.
Established over 2,000 years ago by Alexander the Great, Alexandria is one of the world’s oldest and most populous cities, currently accommodating approximately six million residents. It stands as a particularly vulnerable spot concerning rising seas, posing a grave threat to its historical architecture, which has withstood numerous natural disasters. According to Sara Fouad, the lead author and landscape architect at the Technical University of Munich, current climate change scenarios are rapidly deteriorating the city’s historic integrity.
The research team utilized diverse methodologies to evaluate shoreline changes affecting Alexandria. They developed a detailed digital map to pinpoint collapsed structures and systematically documented their conditions using extensive data obtained from site investigations and official reports spanning two decades. By combining satellite imagery with historical maps from 1887, 1959, and 2001, they illustrated significant coastal shifts occuring within the past twenty years.
Additionally, isotopic analysis of soil revealed that seawater intrusion is weakening building foundations from below. Ibrahim H. Saleh, a soil radiation scientist at Alexandria University, emphasized the alarming nature of this situation. According to the report, even minor increases in sea levels can have catastrophic implications. It is estimated that around 7,000 older buildings in Alexandria currently risk collapse.
Recent incidents have starkly illustrated these risks, including a building collapse in the Wardiyan neighborhood last year that resulted in four fatalities. Similarly, a popular 14-story structure collapsed two years ago, likely due to groundwater damage exacerbated by rising sea levels, as noted by Fouad.
To combat these challenges, the researchers advocate for the establishment of sand dunes and vegetation barriers along Alexandria’s coastline to mitigate seawater intrusion. Steffen Nijhuis, a landscape urbanist from Delft University of Technology and co-author of the study, believes this approach offers a sustainable and cost-effective solution for urban coastal regions worldwide.
Alexandria’s plight resonates with similar threats faced by various Mediterranean coastal cities and regions in California as global temperatures continue to rise. Essam Heggy, a water scientist from USC and a study contributor, highlighted the urgency of the situation, stating, “Our study challenges the common misconception that we’ll only need to worry when sea levels rise by a meter.”
The findings underscore an alarming increase in building collapses in Alexandria due to climate change-induced sea-level rise and coastal erosion. The proposed protective measures of constructing coastal barriers could serve as an effective strategy for safeguarding both the historical integrity of Alexandria and similar urban coastal environments. The study alerts global urban regions to reconsider their vulnerability to rising sea levels and the consequential impacts on infrastructure.
Original Source: www.cnn.com
