With the India Meteorological Department’s (IMD) predicting a below normal monsoon this year, the BMC has revived its plan to try out cloud seeding.
The civic body has written to the Indian institute of Tropical Meteorology (IITM), Pune, requesting technical advice on cloud seeding. Civic officials said cloud seeding would be done only if there is a dire need. “We have sought a feasibility report from IITM in case we need to use cloud seeding this year. We need to make arrangements in advance and also need technical advice on tender requirements so we can be prepared before the monsoon,” said Ramesh Bamble, chief hydraulic engineer, BMC.
Last month, the IMD had predicted that the rainfall this year between June and September is likely to be 95 per cent of the normal, down three per cent from last year’s 98 per cent.
Fearing scarcity of water, the BMC has decided to turn its attention to cloud seeding despite its failure to create artificial rain over Tansa and Modak Sagar lakes in 2009 at the cost of Rs 8 crore.
“Cloud seeding is the process of spreading salts that have hygroscopicity (ability of a material to absorb moisture from the air) on top of clouds of a certain type and size to stimulate the precipitation process and form rain. It is mainly done to increase rain-producing efficiency of a cloud,” said Dr J V Kulkarni, head of the cloud seeding programme at IITM. He added that cloud seeding has been done successfully in other parts of the world and can work if done properly, but it is an experiment.
Although conducted in August or September when the clouds are conducive, the BMC is making arrangements already as permissions necessary for using aircraft and procurement of technology for the experiment takes time, said civic officials. After its 2009 failure, the BMC in 2012 had again tried to perform the experiment by roping in IITM and IMD and Mekorot, a company that has successfully conducted cloud seeding in Israel over the past 50 years.
However, the plan was scrapped after most of the lakes supplying water to the city started to fill up. The proposal had faced flak as the cost had shot up from Rs 12 crore to Rs 24 crore. However, Bamble said cost was not a concern when it is something such as scarcity of water that inconveniences the public.