India’s west coast is far more vulnerable to monster earthquakes and tsunamis than believed till now, scientists have said in dramatic new findings that could force a rethink on the country’s preparedness for natural disasters on a coastline that hosts its biggest nuclear reactor.
Undersea earthquakes as strong as the 2004 Sumatra temblor that spawned a tsunami killing over 220,000 could also strike under the Arabian Sea, off the coast of Pakistan and Iran, striking those countries, India, Oman and further inland, a team of British and Canadian scientists has said.
India’s Arabian Sea coast is home to the 1400 MW Tarapur Power Station near Mumbai, India’s largest operational nuclear plant that in 2011 was also identified by a government expert panel as the least prepared of the country’s atomic power complexes to handle a scenario like the one at Fukushima in Japan in 2011.
The country is also in the process of setting up a 10,000 MW nuclear power complex at Jaitapur that has faced local opposition.
But though the subduction zone – where tectonic plates meet – to India’s west, near Makran along the Pakistan-Iran border is closer to India than the one to the east that was the epicentre of the 2004 tremors, the Arabian Sea has long been considered less vulnerable to large earthquakes and tsunamis.
Unlike the Pacific Ocean and the eastern Indian Ocean, where giant undersea earthquakes are common, the Makran region has been largely quiet after a 7.3 magnitude tremor in 1947.
That view may be dangerously complacent and incorrect, scientists at the University of Southampton, UK and the Canadian government’s Pacific Geoscience Centre have suggested in their research, published in reputed journal Geophysical Research Letters.
“The Makran subduction zone is potentially capable of producing major earthquakes, up to magnitude 8.7-9.2,” Gemma Smith, lead author and PhD student at Southampton said.
“Past assumptions may have significantly underestimated the earthquake and tsunami hazard in this region.”
In 2004, an earthquake of magnitude 9 off the Indonesian coast triggered giant tsunami waves that reached as far as Africa, killing over 12,000 and forcing over 640,000 Indians to flee their homes according to government figures.
The tsunami waves devastated Indonesia, swept away locals and tourists on the pristine beaches of Thailand and Sri Lanka, and claimed lives as far away as Yemen, Somalia and South Africa. The Madras Atomic Power Station in Kalpakkam, on India’s eastern, Tamil Nadu coast, was partially flooded.
After the 2011 earthquake off the coast of Japan and the resulting tsunami that led to the Fukushima nuclear disaster, the worst nuclear incident since Chernobyl in 1986, India’s sole nuclear operator, the Nuclear Power Corporation of India Limited (NPCIL) conducted a safety audit of the country’s nuclear facilities.
The experts on the probe panel concluded that 18 of India’s 20 working nuclear reactors were capable of handling a Fukushima-like crisis – power outage stopping the plant’s cooling facilities and simultaneous flooding from sea water.
But the team found two reactors at Tarapur – first introduced in 1963 – that work on the same principles as the Fukushima reactors vulnerable to tsunami waves and large tremors.