Alexandria experiences a dramatic increase in building collapses attributed to coastal erosion and rising sea levels, with over 280 incidents in twenty years. A significant number of structures are at risk, highlighting a broader global challenge. The study advocates for nature-based defensive strategies and emphasizes the need for sustainable urban planning and preventative measures.
Over the past two decades, Alexandria, an ancient Egyptian city, has experienced alarming rates of building collapses, with over 280 incidents reported. This signifies a tenfold increase compared to previous decades and indicates that more than 7,000 buildings are currently at risk along its vulnerable coastline, according to a recent study published in the journal Earth Future. This trend, which poses a threat to coastal cities worldwide, is primarily driven by severe coastal erosion and rising sea levels attributed to climate change.
Dr. Essam Heggy, a researcher at the University of Southern California and the lead author of the study, emphasized that “Alexandria is a living example of the challenges facing other coastal cities in the region due to climate change and uncontrolled urban expansion.” The implications of this research extend beyond Alexandria to highlight the need for preventive measures globally. Rising sea levels and coastal erosion contribute to seawater intrusion into groundwater, compromising soil stability and foundation integrity.
The researchers utilized a comprehensive approach, analyzing geographic, geological, and engineering data, along with government reports and satellite imagery, to track building collapses. Dr. Sara Fouad from the Technical University of Munich pointed out that their soil settlement analysis revealed a correlation between unstable soil conditions and increased building failures, alongside the statistical analysis of geological changes affecting infrastructure.
The Gharb district of Alexandria is particularly affected, with an average shoreline retreat of 31 meters per year over the past century. Increased salt intrusion into coastal aquifers compromises soil quality and moisture levels. Over-extraction of groundwater exacerbates these challenges. Insufficient building maintenance, poor urban planning, and weak sewage infrastructure contribute to the deteriorating situation. Dr. Fouad argues for a comprehensive risk management approach and sustainable urban planning to address these issues effectively.
While the study focuses on Alexandria, its findings are pertinent to other coastal cities in the southern Mediterranean, including Tunis and Tripoli, which have reported significant structural damages linked to beach erosion. The collapse rates of buildings along Italy’s southern coast have also seen a nine percent increase over the last two decades, raising significant safety concerns.
The study advocates for nature-based solutions, such as green infrastructure and eco-friendly coastal designs to counteract climate change’s impact. Proposed measures such as “living beaches” aim to stabilize shorelines and protect ecosystems, alongside the creation of rain gardens and wetlands to mitigate flooding and erosion. Dr. Fouad advocated for establishing a coastal green street network with salt-tolerant flora to improve water absorption.
Experts like Professor Mattheios Santamouris from the University of New South Wales emphasize the importance of collaboration with local authorities to implement the proposed preventive measures effectively. Moreover, strategies encompassing both adaptation and mitigation, including sea walls, relocating communities from vulnerable areas, and halting the coastal resort expansion on Egypt’s North Coast are necessary to safeguard these regions from forthcoming threats.
The alarming rise in building collapses in Alexandria reflects a broader challenge faced by coastal cities worldwide due to climate change and urban expansion. With over 7,000 buildings at risk, immediate action is required to implement preventive measures and promote sustainable urban planning. The findings underline the necessity for adaptive strategies that include both infrastructural and ecological solutions, ensuring the protection of vulnerable coastal communities in the face of ongoing environmental challenges.
Original Source: www.scidev.net
