We hear it all the time: clean water supplies are dwindling while sea levels are rising. Is there a silver lining in all this mess? Maybe, if we can find a way to convert saltwater into fresh, drinkable water…
The technology for desalination - creating fresh water from sea water by removing salt and contaminants - is nothing new. Though ‘desal’ has only been used in the United States for about eight years, the technology has been around for decades, and is more widely implemented in various water-strapped regions like the Middle East and Singapore. Typically, desalination systems use reverse osmosis (RO) to pass salt water through a semi-permeable membrane. Science.
Presto - you’re using the Pacific Ocean to brush your teeth. Sounds like a perfect solution: salt water in, clean water out. But dig a little deeper and things get tricky.
Existing water laws are complex, and critics of desalination argue that its high-electricity consumption is not only pricey, but creates a net water loss. (In layman’s terms, it costs more clean water to produce the fuel that powers the desalination plant than the plant itself produces. Some environmental scientists and tech skeptics worry about disposal of the leftover, salty waste from the desalination process, while the mass transportation of desalinated water into homes will require costly new infrastructure.
But when those problems are solved, the biggest hurdle left might be the attitudes of Americans themselves. Most experts agree that convincing Americans to treat desalinated water like freshwater will require an aggressive re-education campaign. Others worry that an increase in the amount of available clean water would reduce the incentive for water conservation
Whatever the setbacks, the demand for clean, fresh water will continue to grow.
Proponents of large-scale desalination point to the lack of alternative fresh water supplies as the most pressing reason to use the technology. “You can’t conserve your way out of a water shortage completely,” says Bob Yamada, Water Resources Manager for the San Diego County Water Authority.
San Diego is just one of the many US cities that have hopped on the desalination bandwagon. Residents there will begin receiving fresh water from a new facility in Carlsbad by 2016. As approval for the construction of these plants continues to grow, it seems the United States may be increasing its reliance on water desalination in the future, despite opposition.
Were hoping the technology catches up quickly, while we focus on helping people everywhere, better access and conserve their water resources.
What’s your take on water desalination? Will we “pass the salt…” through a membrane? Or pass on desalination all together?