• Analyzed  the impacts of the desalination discharge on water quality of lagoons and coastal ocean.
  • A fine grid model was used to simulate near-field water quality around the intake and outfall.
  • A coarse grid model was used to simulate water quality in the nearby coastal ocean.

Seawater Desalination at Encina

San Diego County Water Authority  

Carlsbad, CA


The proposed Encina desalination facility involved source water taken from inside Agua Hedionda Lagoon, a tidal lagoon connected to the ocean via a narrow opening, and discharge of brine with the power plant cooling water via a surface channel across the beach north of the lagoon mouth; Flow Science used both a fine grid model to simulate water quality and dilution local to the intake and outfall and a larger grid model to simulate the effect of the discharges, ocean currents, and tides in the ocean near the lagoon. For the Encina study, Flow Science also used ELCOM to predict mixing in the vicinity of the plant discharge. The study area encompassed about 100 square miles of the ocean and also included some inland lagoons. The model can resolve various tidal conditions and plant operating scenarios. The model was compared to existing oceanic data in the vicinity of the discharge and was used to determine the impact of the desalination process on the salinity and temperature in the vicinity of the discharge.