Dispersion of desalination plant brine discharge under varied hydrodynamic conditions in the south of Gran Canaria

Abstract

Brine discharged directly into the sea from desalination processes, forms a very dense plume that spreads out over the sea floor following the steepest slope due to its greater density than ambient sea water. Because the large difference in density slows down brine dilution processes in ambient sea water, hypersaline plumes spread out over broad areas and affect the benthic communities in their path. The Maspalomas II desalination plant, in the south of the island of Gran Canaria (Canary Islands-Spain), discharges brine through an underwater outfall over a wide sandy bottom with a mild slope. The behavior of this brine discharge was characterized under various hydrodynamic conditions. A higher degree of hydrodynamic exposure favored dilution of the outer edges of the plume, helping to reduce the area of influence.