3 Environmental Impacts of Desalination

Did you know that several nations, including the Bahamas, Malta, and the Maldives, use the desalination process to convert seawater to freshwater to meet all of their water needs? But what are the environmental impacts of desalination?

70% of the planet is covered by oceans. In addition to supplying food for almost three billion people, they also absorb 90% of the heat from climate change and 30% of the carbon dioxide that is discharged into the atmosphere. They are also increasingly supplying fresh water to a growing population.

Seawater is not in limited supply, but it is crucial to comprehend and keep an eye on the effects of the constantly expanding number of desalination facilities on the ecosystem.

Desalination is a procedure that converts seawater into a potable resource by taking the salt and minerals out of it. It is very beneficial in locations where water needs are rising as a result of droughts, population growth, and higher water usage. Seawater offers a long-term, sustainable solution to a problem because it makes up the majority of the Earth’s surface.

In many parts of the world, access to clean water remains a big issue. Desalination does, however, carry certain inherent environmental dangers. The way these hazards are addressed and modified will determine the role that desalination plays in the future of sustainability.

Desalination removes salts from water, and as a result, poisonous brine is produced as a byproduct, which, if left untreated, can harm marine and coastal ecosystems.

According to 2018 United Nations research, about 16,000 desalination units are currently in operation in 177 countries and are producing a volume of freshwater that is almost half the size of the normal flow over Niagara Falls. However, if left untreated, the poisonous brine that is typically discharged into the sea runs the risk of polluting food systems.

Water scarcity is becoming more severe in most parts of the world due to increasing water demands brought on by population growth, rising water use per capita, and economic growth, as well as dwindling water supplies due to contamination and climate change.

According to the study, unconventional water sources, like those produced by desalination, are essential to achieving Sustainable Development Goal 6 (to ensure that everyone has access to water and sanitation), but innovation in brine management and disposal is also necessary.

Seawater desalination can increase water supplies beyond those produced by the hydrological cycle. The majority of desalination is now done in industrialized and high-income nations.

The study conducted by the United Nations University Institute for Water, Environment, and Health (UNU-INWEH) Canada Project on Unconventional Water Resources concludes that technological innovations are required, along with innovative financial mechanisms to support the sustainability of desalination schemes, for the rollout of affordable and environmentally friendly systems in low-middle-income countries.

80 percent of the wastewater produced worldwide ends up in our oceans, rivers, lakes, and wetlands.

UN Environment is striving to stop degradation from land-based activities, such as the operation of desalination plants, under the Global Programme of Action for the Protection of the Marine Environment from Land-based Activities. The Global Wastewater Initiative is likewise housed by the Global Programme, which also serves as its secretariat.

With the help of this initiative, people are starting to turn away from garbage disposal and toward resource recovery. It emphasizes capacity development and training, advancing best practices and technology, fostering communication and awareness, and filling in data gaps.

The United Nations Environment Assembly approved a resolution on safeguarding the maritime environment from activities on land in March 2019.

In support of the 2030 Agenda as a framework for sustainable development, Member States also agreed to “enhance the mainstreaming of the protection of coastal and marine ecosystems in policies, particularly those addressing environmental threats caused by increased nutrients, wastewater, marine litter, and microplastics.”

UN Environment wastewater expert Birguy Lamizana says, “Financing wastewater improvements can be difficult, but UN Environment is establishing a facility to engage the private sector to upgrade business models for wastewater management.” To aid in decision-making, it is also developing scientific knowledge and policy recommendations.

Environmental Impacts of Desalination

Construction work may be exhausting, annoying, noisy, and disturbing to the surrounding area.

1. Effects on Marine Life

Impingement and entrainment in the desalination sector are further issues. Marine life, including fish and crabs, may be drawn in and impinge on the intake screen during the intake process when water from the ocean is sucked in. This is known as impingement. Smaller species, such as fish eggs and plankton, may also be drawn in and killed during the treatment process. This phenomenon is known as “entrainment.”

Making the transition from a surface to a subsurface intake procedure can help to lessen this threat. This entails taking water off the ocean floor rather than from the surface, where sand might serve as a natural filter to safeguard marine life. Additionally, this natural filter lessens the need for chemicals and energy during the cleaning process, which can significantly lower expenditures.

There are other options besides a subsurface input process for safeguarding marine life. To incorporate a finer mesh with less room for microorganisms to reach the intake, experts have also discovered techniques to modify screen apertures.

Lowering the through-screen velocity is an alternative. When the through-screen velocity is so great that captured crabs and fish cannot escape, impingement occurs. A velocity of less than or equal to 0.5 feet per second, according to the EPA (Environmental Protection Agency), can effectively manage marine impacts.

2. Energy Consumption

Every business is concerned with energy use, and desalination is no exception. More than 200 million kilowatt-hours of energy are used by desalination facilities every day. A desalination plant’s operational costs are primarily made up of energy expenditures, which makes them particularly susceptible to price hikes.

In contrast, a conventional drinking water treatment facility uses less than 1 kilowatt-hour per cubic meter of water. Reverse osmosis desalination plants need between three and ten kilowatt-hours of energy per cubic meter, the least amount of brine of any desalination technology.

But scientists are still working on less expensive and more environmentally friendly methods to clean seawater. Forward osmosis, which uses a salt and gas solution to create a pressure difference, is one technique being studied. Reverse osmosis membrane lifespan may be extended as a result, and the requirement for disinfectants during treatment may be diminished, according to experts.

3. Contamination of Groundwater

A potential environmental issue is the potential contamination of groundwater aquifers near desalination plants. When constructing feedwater pumps, there is a chance that the drilling operation will contaminate the groundwater.

Groundwater aquifers may be harmed by leaks from pipes that transport feedwater into desalination plants and highly concentrated brine out of them. To avoid this, plants should have sensors and monitoring equipment, and employees should alert plant managers if there are any pipe leaks.

Other significant issues besides brine include air pollution caused by emissions of greenhouse gases (GHG) and other air pollutants. Entrainment and entrapment of marine organisms and extensive chemical use are other problems.

Environmental Impacts of Desalination – FAQs

What is the largest problem with using desalination?

Desalination involves energy-intensive processes and these processes pollute coastal habitats by producing poisonous brine, which in turn contributes to global warming.

Does desalination cause air pollution?

Desalination causes air pollution and this is due to the emissions of greenhouse gasses (GHGs) and air pollutants.

What is desalination and why is it bad?

Desalination is a procedure that converts seawater into a potable resource by taking the salt and minerals out of it. This practice may have a detrimental effect on how the land is used in the community, contribute to erosion, disrupt the visual and aural environment, and release pollutants into the atmosphere and water.

Can desalination cause problems for ocean life?

Desalination leaves behind poisonous brine, which, if left untreated, can harm marine and coastal ecosystems.


Though desalination could have specific negative effects. When figuring out how to effectively address one of the most critical issues in the world—access to clean drinking water—experts are thinking about the creation of brine and the consumption of trash.

Fortunately, innovative approaches are being developed and incorporated to lessen the effects of the desalination process, including the use of modernized filtration and intake systems and solar energy.


Editor at EnvironmentGo! | providenceamaechi0@gmail.com | + posts

A passion-driven environmentalist by heart. Lead content writer at EnvironmentGo.
I strive to educate the public about the environment and its problems.
It has always been about nature, we ought to protect not destroy.

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