Desalination is the process of separating salt and other minerals from seawater or brackish water. This process is found in nature, particularly in mangroves (which grow in seawater and secrete salt through its roots and leaves) and seabirds (which drink salty water if they’re many miles away from freshwater and eliminate salt from their body through their nostrils). But, in most cases, the term “desalination” refers to the artificial process of removing salt and other substances to create fresh, potable water that’s fit for human consumption.
For many, desalination is an important component of modern life, considering that the world’s freshwater resources are slowly dwindling and that many countries and regions are going through water shortages. However, there are also numerous people who oppose desalination and think that it’s not the solution to the world’s water problem. If you want to learn more about this argument, read on to know about the pros and cons of desalination.
List of Pros of Desalination
1. It provides a solution for solve water scarcity.
One of the biggest advantages of desalination is that it’s an effective solution to the global water shortage problem. A few years back, Global Water Intelligence publisher Christopher Gasson pointed out that approximately one percent of the world’s population depend on desalinated water and that this number is expected to rise to 14 percent in 2025. This is particularly applicable for countries and regions that have arid climates and/or are prone to having droughts. Saudi Arabia, for instance, obtained 70 percent of its water requirements from seawater desalination plants in 2011.
2. It’s supported by tried-and-tested technology.
Desalination has been around since time immemorial. Aristotle, for instance, wrote about removing salt from seawater through distillation. Early European explorers, such as James Cook, came up with a crude desalination system so they could have drinking water on board as they traveled to various parts of the world. Because of desalination’s early beginnings, scientists have worked on the process for decades and even centuries and, as a result, they have come up with methods that make the technology feasible. The process isn’t perfect but, unlike other water purifying processes, it’s applicable in daily life and has been proven to be effective.
3. It draws on an almost-unlimited resource.
Desalination is dependent on the world’s oceans so, as long as ocean water is around, people will always have a way to produce fresh, drinkable water. And, since seas and oceans show no signs of drying up (in fact, ocean levels are expected to rise because of global warming and the melting of polar ice caps), it can be said that desalination has a virtually inexhaustible source. Countries and regions that are dependent on this process will always have saltwater to transform into potable water for the years to come.
4. It helps preserve freshwater sources.
Streams, creeks, rivers, and other sources of freshwater are in danger of either drying up or being polluted since many people are highly dependent on them for drinking water. Fortunately, since desalination is dependent on ocean water, it draws people’s attention from freshwater sources and preserves their integrity.
List of Cons of Desalination
1. It requires a lot of energy.
Desalination is an energy-intensive process from beginning to end. Energy is required to siphon water from the ocean into desalination plants, heat thousands of gallons of water (if distillation would be used), or push salt and other minerals through a semi-permeable membrane (if reverse osmosis would be used). This can be a huge disadvantage considering that many other industries (like transportation, manufacturing, and logistics) are also dependent on fossil fuels and that the world’s supply of fossil fuels is already running low.
2. It’s expensive.
Desalination’s dependence of fossil fuel means that millions of dollars would be spent on buying energy for desalination plants. But the cost doesn’t stop there since the plants have special construction requirements and are therefore expensive to build. This isn’t a problem for rich countries like Saudi Arabia, but it can be a big issue for poorer nations whose governments can’t afford to build desalination plants and/or can’t attract investors who would fund the construction of these plants. Even if a desalination plant would be built, the cost of its construction would still be passed to consumers, many of whom wouldn’t be willing to buy expensive water or don’t have the money to pay for it in the first place.
3. It can harm the environment.
Desalination can damage the environment by producing large amounts of salt and minerals that would have to be disposed somewhere and somehow. Unfortunately, most of the disposal techniques that are used aren’t environment-friendly; for one thing, the by-products are treated with chlorine and anti-scaling agents, which can be harmful to vegetation. If these substances are dumped inland, they can pollute forests and freshwater sources and harm plants and animals. If they’re dumped back into the ocean, they can damage the marine ecosystem and destroy the balance that allows aquatic flora and fauna to flourish.
Desalination can also harm the environment through its dependence on fossil fuels, which produce high amounts of carbon dioxide that damage the ozone layer. So, desalination plants essentially produce large amounts of carbon emissions every day and contribute to the greenhouse effect and global warming.
4. It can harm human health.
If desalination’s waste by-products are dumped improperly, they can leach into the water table and pollute drinking water. This, in turn, can lead to health problems in people who would drink the contaminated water, particularly in small children and elderly people. However, many proponents of desalination point out that most desalination plants are placed in industrial areas, which are far away from residential communities and therefore won’t put people at risk. Experts are also looking into safe ways to dispose of by-products to avoid harming human health as well as the environment.
Final Thoughts
Desalination brings a lot of benefits, particularly to areas that are having problems with their water supply, but it also comes with several drawbacks. Governments, scientists, desalination plant owners, and ordinary people should discuss these pros and cons and find a balance between them.
Brandon Miller has a B.A. from the University of Texas at Austin. He is a seasoned writer who has written over one hundred articles, which have been read by over 500,000 people. If you have any comments or concerns about this blog post, then please contact the Green Garage team here.