A biogas treatment process is integrated with a water treatment process to adjust the pH level of the water and to provide more effective disinfection of the water. A water wash process is utilized to separate methane and carbon dioxide present in the biogas. During the water wash process, the biogas is mixed with water and the carbon dioxide is absorbed into the water. Because the process typically occurs at an elevated pressure and reduced temperature to enhance the solubility of carbon dioxide in water, the water stream becomes supersaturated with carbon dioxide. This water stream, which is supersaturated with carbon dioxide, is provided to the water treatment process to adjust the pH level of the water treatment process. The pH level is regulated to a desired level such that an increased relative concentration of hypochlorous acid is produced when sodium hypochlorite is added to the treatment process.