AIZAWL: A survey conducted by Mizoram Remote Sensing Application Centre (MIRSAC) has revealed that 12,705.69 square kilometres of Mizoram which accounts for 60.25 percent of the state's total geographical area, falls under 'seismic zone V', meaning earthquake of high magnitude can rock the mountainous state anytime.
Even though the entire Mizoram is considered to be seismic zone V, a probabilistic method for seismic hazard assessment puts 60.25 percent under zone V and the remaining 39.75 percent under zone IV. Northern parts of Mizoram are said to be more vulnerable to earthquake than southern parts, the survey found.
In terms of vulnerability to wind and cyclone, the Building Material & Technology Promotion Council has indentified the entire Mizoram as very high damage risk zone-A. The survey conducted by MIRSAC further categorised Mizoram into three zones – very high zone (17.68 percent of the total area), high zone (34.50 percent) and moderate zone (47.82 percent). Most parts of southern Mizoram bordering Bangladesh fall under very high zone.
The National Disaster Management Authority (NDMA) has estimated that at least 17,000 people would die if an earthquake with a magnitude of 8 at the Richter scale hit the state capital Aizawl in the middle of the night.
According to GeoHazards International, Aizawl faces a high risk of earthquakes from several major active faults. Annual monsoon rains trigger frequent and sometimes deadly landslides, but even a moderate earthquake would cause massive losses by unleashing hundreds of landslides all at once.
The city's many concrete buildings, built up to ten stories tall without earthquake-resistant features and on landslide-prone slopes–are especially vulnerable to collapse. Poor land use policies and poor construction practices exacerbate the hazards. Aizawl's extremely high levels of risk have overwhelmed local mitigation capacity despite dedicated efforts by local technical professionals, the global organisation has said in its report.