As our climate changes and sea levels rise, there are less fresh water sources available. And as our population grows, there is an even greater need for clean drinking water solutions. One answer to this challenge is ocean desalination, a process that removes salt and other minerals from seawater, making it safe to drink. Desalination seems like a viable solution. But as it turns out, its environmental effects can be devastating.
The Effects of Treatment Plants in the Ocean
Ocean desalination plants are located just off the coast, where their intake pipes suck in billions of fish, eggs, and other small organisms every day, along with the seawater. Once these living organisms enter the machinery of the desalination plant, they are killed. This represents a huge loss of life and could potentially destroy entire ecosystems.
Additionally, the high energy levels needed to run these plants may also contribute to environmental problems. The desalination process requires huge amounts of electricity to separate drinkable water from dissolved salts and other minerals. Burning fossil fuels is the most common method of attaining this energy, which, of course, contributes to air pollution and the greenhouse gas effect.
Mixing Brine Outflow with Natural Seawater
In addition to the machines themselves, another serious environmental concern is the quality of the water put back into the ocean after the drinkable water is collected. This outflow is called brine because of its extremely high salt content (all of the non-salty water has been removed). Not only does brine have more salt than natural seawater, it also commonly contains leftover chemicals and metals from the treatment process.
Components of brine and their related environmental issues include:
- Chlorine: interacts with preexisting chemicals to form carcinogens and mutagens.
- Acids: damage the tissues of organisms.
- Products used for machinery upkeep: cause algal blooms and eventual loss of oxygen in the area.
- Heavy metals: accumulate at the bottom of the ocean where sea creatures ingest them and eventually pass them to humans, where they could be toxic.
How to Reduce the Negative Effects of Desalination
There are many alternatives to ocean desalination for attaining clean drinking water. For example, watershed management, water conservation, and rainwater harvesting, are all viable environmentally-friendly methods.
The negative effects of desalination itself can also be eased by using renewable energy to power the plants, and installing better filters for inflow and outflow.
If there are plans to build a desalination plant in your area, you can attend city meetings to voice your opinion and make others aware of the potentially harmful environmental effects. Local government offices like City Hall should be able to inform you of such plans, or you could try an Internet search for “desalination plants near [your area]”.
For a long-term solution, you can make a personal effort to conserve water. For example, take shorter showers; eliminate leaks in faucets, sprinklers and hoses; turn off the faucet while brushing your teeth and shaving; and use the same water glass throughout the day to cut back on dish washing. If enough water is conserved, it may be possible to eliminate such extreme measures as ocean desalination.