Seawater Desalination


Seawater contains on average 35 g of salt for every litre of water. Salt is one of the hardest things to remove from water and the more salt that is present, the more energy that is required to remove it. There are a number of technologies (electrical, thermal or membrane based) available for removing the salt from seawater to produce fresh water. Of these technologies, membrane based methods like reverse osmosis require the least power so are the most cost effective. Moerk Water seawater reverse osmosis units run at a low recovery rate so they can operate chemical free and make concentrate disposal easier.


  • Produce water directly from the ocean
  • Chemical free operation
  • Energy recovery device to reduce total energy cost
  • Range of capacities available
  • Can be powered with renewable energy

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How does a seawater reverse osmosis system work?

Water from the ocean is usually sourced from a beach well or an ocean intake. Beach wells are preferred as they reduce the complexity of the project and the sand of the well will act as a pre-filter. The incoming seawater is then further filtered and then pressurised to around 50-60 bar. High pressures are required for clean water to flow across the Reverse Osmosis membrane when seawater is used. The pressure from the concentrate is recovered using an energy recovery device to reduce the overall energy cost and the permeate/product is collected for use.

When is seawater desalination the best option?

As one of the most energy intensive water treatment technologies, seawater desalination is used in situations where other water sources are not available. Given the high cost of removing salt from seawater, lower salinity feedwater sources such as brackish and fresh water sources are preferred to seawater desalination. However, given the abundance of clean ocean water available, if there are no sources of low salinity water of sufficient capacity, then seawater desalination becomes the next best option.

Reverse Osmosis Plant and System PROJECTS


Kiribati Institute of Technology Training

Moerk Water strongly believe that water treatment projects will only succeed if local expertise is read more...

  • Community Water Independence - International

Tulia Resort Desalination

Tulia resort in Zanzibar is a luxury boutique hotel on the shores of the Indian read more...

  • Tourism & Resorts
Gilbert Islands Group, Kiribati

Gilbert Islands Kiribati Sea Water Desalination

Kiribati is a remote nation in the Pacific Ocean consisting of 33 islands. Kiribati’s water read more...

  • Community Water Independence - International
Remote Island, Zanzibar Archipelago

Isolated Island Zanzibar Archipelago Desalination

A community based on a remote island in the Zanzibar archipelago was forced to cross read more...

  • Community Water Independence - International
Remote Islands, Tonga

Tonga Disaster Response

In January 2022, the volcano Hunga Tonga-Hunga Ha'apai erupted. Most humanitarian needs were quickly met read more...

  • Community Water Independence - International
  • Disaster Relief

Seawater Desalination APPLICATIONS

Our treatment plants are individually designed to meet the specific requirements to create a supply of water that is safe for drinking or use in commercial and industrial situations.

Tourism, Resorts & Hospitality

Moerk Water units are constructed from quality materials and are built to last ensuring that resorts never run out of clean water. We have extensive experience operating in remote locations. Our units not only provide a decentralised water supply solution, they are powered by solar and wind energy, which removes the need to rely on diesel generators. Our desalinator technology allows coastal resorts can make use of abundant ocean water as a water supply option. They also allow eco-resorts to operate chemical-free, thus minimising their environmental impact.

Remote Communities

We provide desalination equipment and consulting services in countries including Tanzania, Kenya, Somalia, Ethiopia, Myanmar, Solomon Islands, Papua New Guinea, Vanuatu and Kiribati. At Moerk Water we’re proud that our treatment plants have helped communities achieve increased health, socio-economic and environmental outcomes. We work with local communities to empower them to take ownership of the systems we build. This allows often remote communities to maintain and operate their new water treatment technology by providing them with technical training and education. By training local people to maintain and operate the technology, employment opportunities are created in addition to the other health, economic and social benefits that result from our water treatment plants.


Moerk’s water treatment technology can convert a wide range of water types into safe drinking water that meets World Health Organisation water quality standards.

Saline Water

Saline water is easily treatable using one of our desalination treatment systems. Our membrane systems easily remove salt using reverse osmosis. Our engineers can help you to choose the right saline water treatment system for your needs. They are easy to transport and can be adapted to any scale.

Sea Water

Desalination treatment plants are one of our most sought-after systems. Our membrane systems are designed to remove salt and almost all other water contaminants through the process of reverse osmosis. It’s a tried and tested method that we have adapted to be transportable to even the remotest locations as well as adaptable to any scale and completely self sustaining.

Brackish Water Treatment

Moerk Water specialises in designing and building custom desalination plants and systems to treat various saline water sources to achieve water that is ready for commercial application and/or safe drinking water.

UV Sterilisation

Flow Disinfection is the go-to solution when you are treating biologically contaminated surface water. Reverse osmosis will remove all microbiological content from the water and concentrate it into the effluent stream and will also remove the salt.


Typically when we think of reverse osmosis we imagine large facilities that underpin a city’s water supply or small under sink units. However, in our context, we have adapted these membrane systems to be both transportable and optimised for whatever scale various agricultural and commercial concerns require.

Iron Removal Systems

Moerk Water’s Iron Removal Systems remove iron from any water source, eliminating concerns about iron bacteria contamination, corrosion, and scaling. Our iron removal systems utilise aeration mechanisms and filters with an automated backwash to reliably removing iron from the water while keeping the systems hands-free and operating costs as low as possible.

Clarification Filtration

Clarification Filtration is a chemical/physical method to reduce the dirt load in the water. Fine particles below a certain size will pass through standard filters. Following clarification filtration, depending on the water quality required, the water can be further purified to reduce the salt load or remove any other contaminants of concern.