Unknown urban cavities – formation, problem and possible mapping

Urban living captivates the younger generation due to its wealth of prospects and attractive lifestyles. However, it is important to acknowledge that many familiar and unforeseen challenges accompany urban living. This study discusses the most pressing issue of the collapse of urban roads due to the formation of cavities/sinkholes on the subsurface, with scientific reasons and advanced approaches to mapping such cavities in order to reduce urban risk. Sinkhole formations are common in many cities in India, and several such incidents are being reported. Naturally formed sinkholes in lateritic deposits and urban cavities are due to improper handling of the subsurface soil. Typical reasons for the formation of urban cavities are summarized here with scientific explanations based on the density of filling and subsurface water flow. Further, scientific techniques available for identifying such cavities in advanced geophysical methods and the usual procedure for closing these cavities are presented. Regular inspection to focus on the triggering cause and comprehension of the underlying causes and technically designed treatments based on site soils can help prevent cavities from collapsing and subsequent disasters.