Biological activities are initiated as the influent wastewater fills the basin
During the fill and react period, the wastewater is aerated in the same manner as in a conventional activated sludge system
After aeration periods, the mixed liquor suspended solids are allowed to settle in the same basin
The treated supernatant is withdrawn during the draw period
The SBR system can be designed with the ability to treat a wide range of influent volumes whereas the continuous system is based upon a fixed influent floret