After 15 years, Chennai may yet again end up with a grossly deficit northeast monsoon, putting its water resources under severe stress.
Chennai district has recorded a deficit of 55% in rainfall this season and the next one or two days may offer only light rains to few parts of the city. The city has received only 35 cm of rainfall against an average of 84 cm so far, till Saturday. The poor NE monsoon has also reflected on the yearly rainfall, as the city has recorded only 83 cm against its annual total of 140 cm.
According to IMD, the city experienced a cool weather and cloudy sky on Saturday and the same weather pattern may prevail on Sunday. From December 31, the State will head towards dry weather. S. Balachandran, Deputy Director General of Meteorology, Chennai, said such cool weather prevailed on Saturday as westerly winds and easterly winds met near south Andhra Pradesh and moved towards Tamil Nadu.
It may be recalled that the Meteorological Department had forecast that the State was likely to experience a rainfall that would be 12% higher than the normal NE monsoon. “We have still not announced the withdrawal of the northeast monsoon, as there may be a spillover till the first week of January. We are collating data on reasons for the failure of the monsoon,” he said.
Experts note this has been the worst NE monsoon after 2003, when the city experienced 31 cm of rainfall. This had pushed down the annual rainfall to 74 cm and Chennai had faced a severe drought.
Alternative sources
Chennai is bound to face a severe water crisis after a failed NE monsoon for the third consecutive year. While the available resources will last for two months, Chennai Metrowater is already scouting for sources in abandoned quarries of Sikkarayapuram and Erumaiyur near Tambaram, agriculture wells in Tiruvallur district and lakes in Retteri, Ayanambakkam and Perumbakkam.
Bids have also been called for drilling of nine 240-metre-deep borewells in the Neyveli aquifer to transport water to Chennai. However, experts suggest reused water could bridge the shortfall.
Though there have been instances of cloud seeding — an artificial way of inducing moisture in the clouds to cause rainfall — in the past, attempts have not yielded results. Weather experts recall that the State government attempted cloud seeding in 1975 after a poor northeast monsoon in 1974. In May 2003, cloud seeding was attempted but it failed.