If you haven’t noticed yet, we are in the middle of a mega-drought in California.

It’s becoming more and more obvious that water is really our most precious resource. And most of it is shipped in from elsewhere.

But speaking of shipping, there’s also the other stuff that ships are actually floating in. So why can’t we just drink that?

Five things you need to know:

  1. The world is covered with water — 70% of its surface, in fact. But the problem is that less than 1% it is fresh drinking water. Why can’t we drink sea water then? Only because your body won’t last long. It can’t process it, your kidneys will shut down and you’ll get brain damage.
  2. But it’s just salt and water — we can separate it, right? Well, there are two main ways to convert it: reverse osmosis and flash desalination. Both require a lot of energy and special science.
  3. The biggest reverse osmosis plant in the U.S. is in Carlsbad. It sucks in 100 million gallons of sea water every day, where it’s filtered and then pressurized, forcing it through special membranes that trap the larger salt molecules, allowing the salt-free water to flow onwards. The Carlsbad plant produces 50 million gallons every day, enough for 400,000 homes —10% of San Diego’s water needs. 
  4. Well, all that sounds great, but is it a good idea? It’s certainly a brilliant way to make fresh water. However, it’s not without concerns from environmentalists who argue that not only is the process is expensive, but a lot of tiny marine life that are the base layer of the marine food chain can be harmed by the water ingested by desalination plants. And for every gallon of fresh water made, a gallon or more of saline-salty water is returned to the ocean. Environmentalists say that because it’s saltier than the ocean it came from, it has the potential to harm the environment.
  5. With California really parched by a mega-drought, many are saying we need water now, hence a new desalination plant is in the works at Huntington Beach. But others are questioning whether this is all really necessary. If we just get super-efficient at recycling the water we already use, we won’t need to make more!

Either way, we have to solve it fast, as water is only going to become a more and more precious commodity. It's something that we may see as our birthright, but if we don’t act soon, we could be in for a very thirsty future indeed.