We can tackle water scarcity while protecting our planet
As communities across the world are increasingly facing water scarcity, desalination offers a solution for providing fresh water in arid regions and coastal communities. Fresh water makes up only 2.5% of the earth’s water, while seawater accounts for around 96.5%.
Desalination technology allows us to turn seawater or brackish water into potable water, providing a potential long-term solution to the water demands of a rapidly expanding global population. However, this solution comes with environmental considerations. Balancing the benefits of desalination with the need to protect ecosystems is essential for sustainable implementation.
The Growing Demand for Desalination
Global water demand continues to outpace supply because of population growth, urbanization, and climate change. According to UNICEF, nearly 2 billion people live in areas plagued by water scarcity, and this number is expected to rise. Desalination can provide a reliable and consistent water source. Countries like the United Arab Emirates, Saudi Arabia, Israel, and Australia have embraced desalination to help fulfill their water needs.
The total global desalination capacity has increased from around 5 million cubic meters per day in 1980 to 20 million cubic meters in 2000, rising to 90 million cubic meters in 2020, and is projected to continue growing. Desalination is not without its environmental considerations. However, advancements in desalination technology are continuously addressing these challenges. Energy-efficient processes and innovative brine management solutions are minimizing the environmental footprint of desalination plants.
Overcoming Environmental Challenges
Seawater reverse osmosis (SWRO) desalination is a process where seawater is forced through membranes with tiny pores that trap salt and other impurities while allowing water molecules to go through, resulting in potable water. This process involves several stages, each with potential environmental impacts:
Seawater intake and biodiversity loss: Seawater enters the desalination plant through an intake system that can inadvertently harm marine organisms. Fish, larvae, and other creatures can become trapped during water intake, leading to the loss of biodiversity and disrupting local food chains. While the intake is covered by a screen or filter to prevent marine fauna and flora from being sucked into the system, there is a risk of small organisms passing through the screen (entrainment) and larger marine animals can get pinned against the screen by the force of the water flowing into the intake (impingement).
To prevent the impingement and entrainment of marine life, Seven Seas Water Group employs low-suction velocity pumps and other prevention measures, such as a net to cover the raw water intake. Subsurface intake systems, which draw water from beneath the ocean floor, can significantly reduce the intake of marine organisms. These systems act as natural filters, protecting marine life while ensuring high-quality water for processing.
Seven Seas’ Trinidad team completes one of our environmental stewardship projects, adding a screen to the submerged seawater reverse osmosis intake at one of our desalination plants.
Energy consumption: While traditional processes may have required significant energy, advancements in desalination membranes and energy recovery devices have significantly improved efficiency. This not only reduces the carbon footprint but also makes desalination more cost-effective and sustainable.
Brine discharge and marine ecosystems: A byproduct of desalination is large volumes of highly concentrated brine, which is often discharged back into the ocean. While brine discharge is a consideration, desalination plants are increasingly adopting innovative solutions like brine treatment and reuse to minimize environmental impact.
Wastewater treatment technologies that concentrate and repurpose brine into valuable byproducts, such as salt, minerals, or chemicals for industrial use, are gaining traction. Diffuser systems that dilute and disperse brine more evenly in the ocean, along with monitoring programs that allow plant operators to adjust brine discharge levels, can minimize the impact on marine ecosystems.
Sustainable Desalination: A Case Study
Several projects around the world demonstrate that desalination can be both effective and environmentally responsible. The desalination plant serving the community at Point Fortin on the Caribbean island of Trinidad delivers 6.7 million gallons of potable water per day to 29,000 residents, while implementing measures to protect the sensitive marine environment.
For this project, Seven Seas conducted a thorough environmental impact study on the surrounding marine ecosystem. To prevent the impingement and entrainment of sea life, including endangered turtles found in local waters, Seven Seas installed low-velocity pumps and a net that covers the submerged raw water intake. Seven Seas also launched an environmental management program that includes monitoring effluent quality as well as ecological surveys to assess the impact on the surrounding ecosystem.
Desalination is a valuable tool in the fight against water scarcity, but it must come with a commitment to environmental stewardship. By embracing sustainable intake systems, energy-efficient technologies, and innovative brine management solutions, we can strike a balance that safeguards our water supply and the environment.
As a global leader in desalination, Seven Seas leverages decades of expertise to deliver reliable, sustainable water solutions. With a track record of more than 200 plants and an industry-leading 97% availability, Seven Seas is committed to providing water security without compromising environmental integrity. Contact our team to explore how our solutions can meet your water needs sustainably.
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