Researchers find saline groundwater better water source than seawater

Israeli researchers have found that brackish groundwater from coastal aquifers serves as a better water source option than seawater for reverse osmosis (RO) desalination due to reduced pre-treatment costs and membrane fouling.

This study was carried out by researchers of the Ben-Gurion University (BGU) Zuckerberg Institute for Water Research, the BGU Department of Geological and Environmental Sciences and the Israel Geological Survey.

BGU Zuckerberg Institute’s Department of Desalination and Water Treatment senior lecturer Dr Roni Kasher was quoted by Floridawaterdaily.com as saying: "Decision-makers in both California and Israel can use this research to seriously consider saline groundwater as a realistic alternative when planning future large-scale seawater desalination facilities.

"In Israel, seawater desalination accounts for 60% of the total freshwater supply, so these findings are significant."

BGU researcher Shaked Stein was quoted by Azocleantech.com as saying: "Saline groundwater results from seawater intrusion into coastal aquifers, shifting the fresh-saline water interface upward and landward, and replaces fresh groundwater with saline groundwater. The RO process in coastal aquifers will be helpful in restraining seawater intrusion."

Brackish groundwater offers other benefits, which include water temperatures at consistent level, and low levels of dissolved oxygen, phytoplankton and silt density.

The desalination process of seawater through RO requires energy, as well as significant facility area, which in turn increases the cost factor.

Stein added: "The study showed that aquifer filtration increases the feed water quality and reduces the need for extensive pre-treatment processes.

"RO desalination with saline groundwater as feed water is also more efficient, with higher freshwater recoveries, less chemical use and maintenance, and therefore less overall operational costs."