A good rain is not good enough

On July 1, the Brihanmumbai Municipal Corporation (BMC) announced a 15 per cent cut in water supply because of ‘inadequate rainfall’. The following day, it released data that said four lakes in Thane district — from where 98 per cent of Mumbai’s water comes — had received more than the normal amount of 518 mm, as specified by the Indian Metereological Department (IMD).

BMC’s figures showed that Bhatsa lake got 675.2 mm of rain — 30.3 per cent more than normal. The lake that received the least rainfall, Tansa, got about 5 per cent more than normal. IMD figures showed that Thane got 682 mm of rain, 32 per cent more than normal.

However, all that water is not enough for a thirsty monster called Mumbai, with 16 million-odd heads and growing.

“Up to July 3, rain over the lakes was quite good and all above average,” said P.N. Guhe, deputy hydraulic engineer, BMC. “Mumbai’s demand has been steadily increasing. And since we had no water cuts this summer, more water was drawn from the lake.”

BMC Hydraulic Engineer M.M. Kamble reiterated that the rains were not enough: “Monsoon has not been adequate this year to meet the demand.”

But how much rain is enough to supply Mumbai with interrupted water? A BMC source said even 40 per cent more than normal rain would not suffice.

“There is no deficiency in rainfall in Thane, Mumbai and Raigarh so far,” said K. Sathidevi, director, forecasting, western region, IMD. “If it rained more than double in the last three years, it cannot be taken as normal.”