Indeed, the byproducts of the desalination process, namely brine water, once discharged into the sea, locally disrupt the fauna, flora, and, more broadly, the ecosystem it inhabits. This is a challenge Morocco must address, as highlighted by Tarik Hamane, General Director of ONEE, in an interview with TelQuel: “One of the major challenges facing the seawater desalination industry concerns its environmental impact.”
The office thus aims to adhere to the highest standards for preserving ecological balance and biodiversity. Whether through its internally adopted specifications or the strict criteria imposed by funding agencies, ONEE strives for excellence in this regard.
“In all our projects, whether for water or electricity, we follow the best standards in terms of environmental impact. These programs are funded by financial institutions that are also very attentive to such impacts,” explains Tarik Hamane. He adds, “For each project, we conduct environmental impact studies, human impact assessments, noise impact evaluations, etc. We therefore have key performance indicators to meet.”
“One of the major challenges facing the seawater desalination industry concerns its environmental impac”
Specifically, effluents from desalination plants can reach temperatures more than 4°C higher than their discharge environment, while being significantly more saline and far less oxygenated. These characteristics can have harmful consequences near discharge sites.
“There is a detailed study on the discharges from desalination plants, particularly the brine water. What you need to know is that when we extract water for desalination, 40% of the volume is converted into drinking water, while the remaining 55 to 60%, which is more concentrated in salt, is discharged. The salt concentration in this water is about twice as high as that of the water initially taken,” explains the General Director of ONEE.
“When we discharge it, it is done through an outfall placed sufficiently far into the sea. Depending on the case, this can extend up to 2 kilometers from the shoreline. This is what has been planned, for example, for the Casablanca desalination plant. Additionally, studies ensure that the salinity level beyond a radius of 300 meters from the discharge point remains unaffected. The design is based on this principle,” he adds.
Not far from our shores, the El Atabal desalination plant in Malaga, Spain, stands as a model. The station, which not only meets but exceeds the city’s drinking water needs, produces approximately 165,000 cubic meters of desalinated water daily. Its discharges are transported through an outfall more than 6 kilometers long. Are Moroccan desalination plants, therefore, truly up to international standards?
Tarik Hamane maintains his stance: “The effects on the Mediterranean Sea are more visible than on the Atlantic Ocean, where most Moroccan desalination plants are located. What needs to be emphasized is that there are three factors to consider when talking about discharges: the first is salt concentration, then depth, and finally temperature. The Andalusian station, for instance, discharges into the Mediterranean Sea, which is saltier than the ocean, its waters are less deep, and the temperature is therefore higher. This explains the significant distance between the discharge point and the shore,” explains the Director General of ONEE.
However, brine water can be repurposed. It is indeed possible to extract chemical components that can be utilized, such as hydrochloric acid, magnesium, soda ash, or even lithium.
Written in French by Amine Belghazi, edited in English by Eric Nielson