Breathing life into an old human dream

Making fresh water from seawater is engaging the world’s attention, and India’s. Is small still the beautiful way of doing it?

Hopes are sometimespinned on desalination technology to meet the huge needs of water of the planet‘s thirsty millions.
Mr. Chidambaram announced with much fanfare a walloping Rs 4000 crore allocation for the creation of an ambitious desalination project to be put up on the east coast in Tamil Nadu.
This is not an exciting new development. Experts were even predicting as long ago as the early 1960s that water produced from seawater would become competitive by 1980. That didn‘t happen. It is an old dream of humanity: to transform seawater into drinking water.
And indeed the promising signs are continuing to multiply. Some say that the cost of a cubic meter [1000 litres] of desalinated water has fallen from Rs 500 or more a decade ago to Rs 60 today. Others, basing themselves on the results of the experimental plant at California state, insist that the cost has already fallen as low as Rs 25 for 1,000 litres. But constantly falling prices are not enough for the desalination of seawater to become widespread in the next 15–20 years, and thus to help solve the water supply problem in the many countries faced with shortages.
Two serious obstacles remain to the advance of desalination: one is that the production of hundreds of millions of cubic metres of desalinated water would require enormous quantities of energy, thereby increasing carbon dioxide emissions into the atmosphere and worsening the global warming impact; the other is that the dumping of residual waste water at high temperatures into the open sea would be a major source of marine pollution.
Technology can help, but it cannot guarantee the right to water for the 1.4 billion people around the world who are today deprived of it. That equals the entire population of China, well almost. If nothing is done to reverse the present trend the number of people without access to drinking water in 2025 will rise above 4 billion—that‘s half the world‘s population then. Today, there are more than two billion who have no system for domestic sanitation or purification of waste water.
Neither is technology the means to solve the interstate conflicts that threaten to become more widespread and acute.
This has to be part of some sort of ‘first revolution of the twenty-first century‘.
— C N Patil