Water Quality Improvements with the Use of Ozone at the Los Angeles Water Treatment Plant

Abstract
At 600 mgd (2,270 ML/day), the recently completed Los Angeles Aqueduct Filtration Plant (LAAFP) is one of the world's largest water' treatment facilities utilizing ozone for pretreatment. The treatment process features direct filtration at rates of up to 13.5 gpm/ft2 (33 m/h). Under the optimized full-scale operation, preozonation has resulted in significantly reduced THM levels and very low effluent turbidity with low operating costs.