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Maharashtra announced the setting up of a desalination plant in Mumbai, becoming the fourth state in the country to experiment with the idea. 

What are desalination plants?

• A desalination plant turns salt water into water that is fit to drink.
• The most commonly used technology used for the process is reverse osmosis.
• The microscopic pores in the membranes allow water molecules through but leave salt and most other impurities behind, releasing clean water from the other side.
• These plants are mostly set up in areas that have access to sea water.

In India, Tamil Nadu has been the pioneer in using this technology, setting up two desalination plants near Chennai in 2010 and then 2013. 

What is the need?

• According to the BMC’s projection, the population of Mumbai is anticipated to touch 1.72 crore by 2041 and accordingly, the projected water demand would be 6424 MLD by then.
• Currently, BMC supplies 3850 MLD as against the requirement of 4200 MLD each day.
• In 2007, a state government-appointed high-level committee had suggested setting up desalination plants in Mumbai.

Issues

• Desalination is an expensive way of generating drinking water as it requires a high amount of energy.
• The other problem is the disposal of the byproduct — highly concentrated brine — of the desalination process.

 Source: Indian Express