Wetlands as Water Purifiers: Does Nature Do It Better?

Would you associate an aluminum refinery with an innovative water pollution solution? An aluminum refinery called Ma’aden in Saudi Arabia is taking a creative and cost-saving step to purify polluted industrial water. Ma’aden is trusting wetlands—nature’s water purifier. 


Vegetation in the man-made wetlands stimulates the growth of microorganisms that remove impurities from the wastewater more effectively than a conventional tank-based purifying system. A tank-based purifying system requires workers to fiddle with controls in order to correctly target pollutants in the water. The wetlands eliminate the need to mess with controls. Wetlands naturally degrade dangerous pollutants, requiring far less work.

Not only are the wetlands less work once constructed, they are also far more cost-effective. Wetlands require no maintenance, are pleasing to the eye, and consume zero electricity.

Ray Kilmer, who worked with the Ma’aden team during the wetland project, explains: “The wetlands provide a better mechanism for cleaning the water, helping the earth use its own processes to heal itself, and don’t require sophisticated controls… it’s also less cost, more effective, and more robust” (The Guardian).

Less cost, more effective, and more robust, the wetlands also offer a stopping ground and refuge for migratory birds, creating an ecosystem and oasis in the Saudi Arabian desert.

Wetlands increase biodiversity, trap polluted sediment, and greatly reduce pollutant concentrations without using the energy or fossil fuels required to operate a conventional water purification system. The natural water-purification process that occurs in wetlands is known as biofiltrationBiofiltration is defined as pollution control that uses living material to capture and degrade pollutants.

Biofiltration happens as surface water flows through vegetation. Pollutants are removed as plants uptake and process water, as sediment settles into the gravel and soil, and as microorganisms consume pollutants.

The types of plants used in a biofiltration system depend on the targeted pollutants. Floating plants derive carbon dioxide and oxygen from the atmosphere, and remove minerals from the water. Submerged plants remove carbon dioxide, oxygen, and minerals from the water, but require relatively clear water because they need sunlight to photosynthesize.

Phytoremediation refers specifically to the use of living green plants to degrade contaminants. The degradation of pollutants occurs in different parts of the plant, or in different types of plants, depending on the type of pollutant.

The table below exhibits how different pollutants are targeted by plant part and plant type:


The use of biofiltration to clean large amounts of wastewater is a relatively new idea and has not yet taken popular hold. There is little awareness of the biofiltration alternative to traditional tank-based water purification. As awareness spreads, so does willingness to change.


If we want to see biofiltration replace conventional techniques, we can share the concept. If people are not aware of biofiltration, how can we expect the concept to become popular? When we share the concept, whether it is over coffee with a friend or from the podium at a City Council meeting, knowledge spreads.

You can:

Share biofiltration with representatives in your town, city, state, and country. Push for legistlation and projects that support biofiltration and phytoremediation. Do whatever you feel comfortable with, even if it is speaking with your family at the dinner table—all action makes a difference.

In our communities, cultures, and world, we can continue to discuss ideas and to take action to heal our water sources and to remove pollution. We can share potential solutions and engage in debate and conversation surrounding the world we want to build. Do we want more efficient, clean, and healthy water filtration systems? Then it is time to speak out. Do we want to heal the delicate environmental balance that provides clean water for us to drink? Then it is time to take action.

Would you like to see biofiltration replace conventional tank-based water purification? Do you think biofiltration is a viable option? We’d love to hear your thoughts! Please leave a comment below.

Our project is working in harmony with water.org to provide access to safe water. We hope “to break the cycle of poverty”, “to protect and save lives”, and “to make a bright future possible for all”: Make A Difference Donation