Heavy rains that sank Chennai city in 24 hours was the highest rainfall in the last 10 years, says the Met department. Chennai had 246.5 mm rainfall in the last 24 hours which breaks the record of November 2005 which saw 142.4 mm, said Thambi Narayanan, deputy director general, meteorological department, Chennai.
He said the highest rainfall during the north-east monsoon was in November 1976, when the city recorded a rainfall of 452.4 mm.
“There will be heavy rain in Chennai although it is not going to be as severe as last night. It is all about the intensity of the rain and how far it continues with that same intensity. There may be rains in the coming days too but it would be moderate. This was something we anticipated in September itself but we had alerts too that it would be above normal,” he added.
Unlike the north-east monsoons in the previous years, what makes this year’s rains different is that it was neither a depression nor a cyclone but a low pressure that played havoc with people’s lives. This low pressure system formed near Sri Lanka before moving northwards.
Visiting rain-affected areas in the north of Chennai, Chief Minister J Jayalalithaa said, “damages due to very heavy rains was inevitable.” She promised immediate assistance from the government to all the affected people.
However, when the Met department alert in September 2015 warned of an above normal rainfall and the same was conveyed to the government as well as to the city authorities, the corporation of Chennai did little to prepare for the situation. Making tall claims of preparations, the corporation issued statements detailing the quantity of silt already removed from drains and boasted of super suckers, jet-rod machines and desilting machines used to clear water off the roads.
Going by the scenes in various parts of city on Monday including Koyambedu, one of the busiest locations that handles thousands of inter-city buses, it looks like the tall claims of the corporation that the city will not sink were washed away in 24 hours of rain. It is evident that the storm water drain projects that drained out several crores rupees in the past two years were still clogged.
Questions being raised now are not just about the desilting contracts in the last few months but also about the multi-crore storm water drain projects and their technical aspects. Sometime in July 2014, a Chennai Metropolitan Development Authority (CMDA) engineer wrote a confession letter to his boss detailing how his superiors executed a multi-crore storm water drain project at Koyambedu without concrete reinforcements or cement but with quarry dust.