The main objective was to assess the treatment efficiency of a clay and TiO2 based system for removing pollution from lake waters, specifically Lake Antagnavo. Analysis of physicochemical parameters (pH, conductivity, suspended solids, turbidity, nitrite, nitrate, phosphate, and chloride levels, COD, and BOD) and bacteriological parameters (ASR, fecal coliforms, fecal streptococci, and Escherichia coli) allowed for the evaluation of the treated water quality. The model reduced the amount of physicochemical pollution in the wastewater at the end of treatment. The pH ranged from 6 to 9, the conductivity decreased from 429.33 to 273 µS/cm, the turbidity was 17.8 NTU, and the suspended solids varied from 12.5 mg/L. Nitrite and phosphate levels are 0 mg/l. Nitrate and chloride levels are 11.82 mg/l and 26.08 mg/l, respectively. BOD5 is less than 50 mg/l, and COD is less than 150 mg/l; all values comply with discharge standards. According to these results, 99.78% of fecal streptococci, 99.64% of ASR, 97.84% of fecal coliforms, and 98.43% of Escherichia coli are eliminated. Microbiological and physicochemical parameters reveal that the treated water is qualitatively improved.