Challenge:
The treatment facility faced high chloride levels in the wastewater due to levels in the water supply and use of residential automatic water softeners.
While community bans on automatic water softeners had made significant progress in reducing chloride levels, SCVSD needed to make additional gains to meet a 100 mg/L state mandated limit on chloride.
Solution:
SCVSD selected SUEZ’s proposal to supply high pH reverse osmosis technology because it offered the best overall lifecycle costs for the facility and had a demonstrated track record of high salt removal and water recovery rates.
SUEZ worked with the LACSD design team to develop a system that will purify a portion of the plant’s treated water, removing nearly all of the chloride from this side stream. The purified water will then be blended with the treated water to bring chloride levels below the 100 mg/L limit.
SUEZ’s proven track record of providing water systems with exceedingly high water recovery rates was one of the deciding factors for the project. The high pH reverse osmosis system will treat 8 million gallons per day with a projected water recovery of 99.2%. The high water recovery rate greatly reduces the volume of brine requiring disposal and allows for brine disposal via a limited number of trucks per day.