Water, water everywhere, but Mumbai remains thirsty

MUMBAI - Mumbai falls in the rain-abundant coastal Konkan region of western Maharashtra, but this summer the city is practically thirsting for drinking water.

The rains played truant in the 2009 monsoon, leaving a deficit of nearly 25 percent of the season’s total rainfall and consequently, the 14 million-strong population has to bear the brunt. The limited supply this year has led to water cuts ranging from 15 to 30 percent imposed by the Brihnmumbai Municipal Corporation (BMC).

The problem has been compounded by the frequent bursting of major pipelines during the past three months - over two dozen instances - in which millions of litres of the precious liquid went down the drain.

A worried Municipal Commissioner S. Kshatriya announced Friday that all the old, damaged and weak pipelines would be replaced, starting with the 43-km- long Tansa Lake pipelines coming from Thane and another 17 km running within the city, at a cost of around Rs.12 billion.

A senior official of the hydraulic department said that replacement of small and medium pipelines is an ongoing affair in the BMC. A total network of over 4,000 km water pipelines run within Mumbai, plus many more outside the city.

According to top civic officials, the 437 sq km Mumbai island, surrounded by the Arabian Sea on all sides, has limited sources of water for drinking and non-drinking purposes.

The demand keeps growing with the influx of people into the city but the supply has remained constant, they point out grimly.

Mumbai needs around 3,500 million litres per day (MLD), or approximately 200 litres gross per head for drinking, cooking, cleaning and washing.

There are six lakes, two in the city and four on the outskirts, which supply water, plus around 14,000 old and new wells and borewells dotting the city, while the Powai Lake in Andheri caters to industrial uses.

Besides these, there is the notorious Mithi river flowing from the 100-sq km Sanjay Gandhi National Park in north Mumbai in four branches through the suburbs.

The river is heavily polluted today, though barely three decades ago freshwater fish from the Mithi river was abundantly available in local markets.

The official said that since October 2002, the BMC has made it compulsory for all properties (plots) above 1,000 sq metres to implement rain water harvesting (RWH) schemes.

In 2007, the norm became stringent with all properties above 300 sq mt made to comply with RWH schemes and all buildings with central cooling systems to implement water recycling techniques.

Though it can be implemented with minimal costs, of the 310,000 properties, a little more than 1,000 have till date implemented RWH.

In other areas, RWH cannot be strictly enforced or implemented as Mumbai is an island. The existing high groundwater coupled with the rain water harvesting has led to cases of unseasonal flooding.

The total potential of RWH is estimated at 600 MLD. It is much higher than the 455 MLD supplied by the Middle Vaitarna River Project, one of the biggest lakes that partly meets Mumbai’s need.

“Safe and clean drinking water in Mumbai is made available very cheap by the BMC at Rs.3.50/1,000 litres for residential purposes and Rs.35/1,000 litres for commercial users. So most people are reluctant to implement RWH,” explained a senior official.

Instead, the BMC is striving to make people change their water usage habits, even roping in cricket maestro Sachin Tendulkar who said that he uses a bucket to bathe to save water.

The BMC has taken up several pilot projects on 20 large civic and government properties and managed to save huge quantities of water.

“Mumbaikars must realize the need to use water sparingly and ensure no wastage. Today it is very cheap, but after 10 years it may not be so,” the official warned.

Now the BMC is actively considering setting up a desalination plant to cleanse sea water for drinking purposes - the hitch is that it could be an expensive proposition, both for implementation and for the consumers.

(Quaid Najmi can be contacted at q.najmi@ians.in)