A variable process for treating wastewater at a localized sewage treatment system positioned at the site of the wastewater generation is disclosed. Wastewater initially flows from a residence or business into a first operational area of the wastewater treatment system where a majority of the solid material in the wastewater is allowed to separate out of the wastewater. The wastewater is transferred from the first operational area to a second operational area. At a predetermined transfer time, if the wastewater in the second operational area is at least equal to a predetermined transfer volume, a batch of the wastewater is transferred from the second operational area to a third operational area. The batch of wastewater in the third operational area is aerobically treated for an amount of time based on the volume of the batch of wastewater. The treated wastewater is then transferred from the third operational area for dispersal.