MUMBAI: Having failed to make artificial rains despite 160 attempts in 2009, the civic body will resort to the same technique this year to make for the shortfall. On Thursday, the Brihanmumbai Municipal Corporation (BMC) will hold a video conference with officials from India Meteorological Department (IMD), Indian Institute of Tropical Meteorology (IITM) and Israeli firm Mekorot to decide on cloud seeding methods in catchment areas of lakes supplying water to the city. Mekorot will assist BMC with technological infrastructure like radar and aircraft.
Though civic officials admitted that last time they were unsuccessful, they said this year they are trying to correct the past mistakes. “This time we are doing it under expert guidance, as we had not sought help from agencies like IMD and IITM earlier. After discussing it with IITM they have come to a conclusion that cloud seeding is now a well established science. It’s a proven thing that cloud seeding makes inefficient clouds efficient,” additional municipal commissioner Rajiv Jalota said.
IITM has told BMC that Israel has extensively developed its technology on cloud seeding and has been using it for over 50 years. “Fortunately, we had a MoU with Israel’s water and energy department in June, last year. Since the past 15 days, we have been in touch with Israel’s national water company Mekorot to undertake this experiment,” he said.
In 2009, attempts were made over Tansa and Modak Sagar lakes with the help of Hyderabad-based Agni Aviation and the civic body spent Rs 8 crore on the project. Civic officials from the hydraulic department claimed that the experiment failed as BMC was unable to calculate the difference in amount of rainfall in catchment areas after cloud seeding was carried out.
Jalota said that the last experiment in 2009 at Tansa and Modak Sagar was done with the help of an aircraft and also by burning silver iodide crystals.
This time around, the experiment will involve sprinkling of silver iodide on clouds over Tansa, Bhatsa, Upper Vaitarna and Modak Sagar lakes to induce precipitation and subsequently artificial rains. “The technicians will be sitting inside the aircraft to monitor every step. The cloud seeding will be done at the base of the cloud when the cloud is having an updraft and has a reflectivity between 30dbz and 35dbz. This is the time the cloud is best suited for cloud seeding. It takes half-an-hour for the clouds to be efficient and it rains. The average speed of the cloud will be 15 metres per second,” Jalota said.
He said the civic body is in touch with Mekorot’s Mumbai base in Bandra Kurla Complex. “The modalities will be worked out on Thursday, whether or not to use IMD’s radar. We will also decide on whether Mekorot will provide us with just the aircraft or even manpower to operate the aircraft,” said Jalota.
If all goes well, Mumbaikars will also get an additional 455 million litres per day, as gates of Middle Vaitarna dam will be opened and water from the dam will be released by September.
Don’t make water supply out to be rocket science
The BMC should stop looking at outlandish ideas for maintaining supply to taps. Statistics indicate that Mumbai would not have to go through water cuts had the BMC simply turned its attention to plugging the leaks in the distribution chain and the widespread pilferage. The BMC has managed to keep the level of water cut down to 10 per cent this year but some long-term planning and attention to basic details could have done away with even this bit of pain.
- Predicting the monsoon (thehindu.com)
- Weather experts to visit State next week (thehindu.com)
- Mumbai: BMC announces 10 per cent water cut (ibnlive.in.com)