Why Mumbai is set to face a 10% water cut as early as February this year

In what has emerged as a larger concern for citizens, the possibility of an early water cut comes at a time when weather experts have sounded alarms over a harsher summer this year, with more frequent heat waves sweeping the state.

Amidst the possibility of a water cut looming large, The Indian Express spoke to BMC officials and weather experts in a bid to understand why the city is staring at a slash as early as February this year.

How much water cut is the BMC considering and why?

As lake levels dipped below 50 per cent, civic officials have said a 10 per cent water cut will be imposed by February end, if the irrigation department does not give a positive nod to the civic request for extra water.

P Malwade, an engineer with the civic hydraulic department, told The Indian Express that in their letter to the irrigation department, the civic body has made a request for extra 1.37 lakh million water from the Bhatsa lake while from Upper Vaitarna, a request for allocation of extra 93,500 million litres of water has been floated.

“We have also requested the irrigation department to intimate us by this month’s end. If we do not hear from their end, then we will impose 10 per cent water from this month end to mitigate any water crisis in the upcoming months,” added Malwade.

Last year, the BMC had imposed a cut on July 1 — thanks to a delayed monsoon onset — and withdrew it on August 8.

Why have Mumbai lake levels depleted faster this year?

While the water stock on Tuesday dipped to half its total capacity, the lake levels stood at 54.89 per cent on the same day last year. In 2022, the stock had remained at 57.39 per cent.

According to AMC (Projects) Velrasu, lake levels have lowered faster this year owing to less rainfall in September end and October during monsoon. After a delayed onset of monsoon last season, the city experienced an early withdrawal that was announced on October 7 — four days prior to the official date.

Even as the lakes had managed to fill to the brim — with the total water stock touching 99.24 per cent by October 2 — the stock has halved at a faster rate, because of the earlier than usual withdrawal. “Last year, strong monsoon showers stopped after September 27. In the past two years before that, however, we got monsoon till as late as October 20,” said Malwade.

Besides this, weather experts from the India Meteorological Department (IMD) also pointed to the warmer winter this season as being another leading cause for faster evaporation of the lakes.

Why is this cause of larger concern?

The fast depleting lake levels have raised further concerns as weather experts have indicated that this year, summer is slated to be harsher than usual. Warmer summers will lead to faster evaporation in the lakes leading to faster decline in stock.

“Owing to El Nino, we are expecting more frequent heatwaves in the upcoming summer months. This year, Mumbai has even seen a warmer winter. Now, if the El Nino persists, there is a possibility of a warmer summer as well. This can create difficulties as the water levels can deplete faster,” said an expert from the weather bureau, requesting anonymity.

Mahesh Palawat from Skymet Weather Services said, “El Nino years are generally warmer and thus, this summer could be harsher. The temperatures will remain marginally higher than normal and there is also a possibility of heatwaves across India”.

However, Sunil Kamble, Director, IMD Mumbai, maintained that the official forecast for the upcoming summer months will only be released by February 29.