高普考/三四等/高員級◆英文題庫下載題庫

With the increasing water shortages and growing water conflicts, some people start to ask: why don’t we get our drinking water from the ocean? The problem is that the desalination of water requires a lot of energy. Salt dissolves very easily in water, forming strong chemical bonds, and those bonds are difficult to break. Energy and the technology to desalinate water are both expensive. There are environmental costs of desalination as well. Sea life can get sucked into desalination plants, killing small ocean creatures, and upsetting the food chain. Also, there’s the problem of what to do with the separated salt. Pumping this super-salty water back into the ocean can harm local aquatic life. Reducing these impacts is possible, but it adds to the costs. Despite the economic and environmental hurdles, desalination is becoming increasingly attractive as we run out of water from other sources. We are over-pumping groundwater, we have already built more dams than we can afford economically and environmentally, and we have tapped nearly all of the accessible rivers. Far more must be done to use our existing water more efficiently, but with the world’s population escalating and the water supply dwindling, the economic tide may soon turn in favor of desalination.