A thorough site evaluation must be conducted in order to determine the appropriate level of pretreatment prior to final onsite subsurface disposal of the greywater portion of the wastestream. Septic tanks can provide for only primary levels of treatment. Odors may be emitted from incinerating toilet units. The ash product from these units must be properly disposed. Energy Consumption Septic tanks do not require power consumption.
Wastewater drains by gravity from the house to the tank.
Aesthetic Considerations Septic tanks are buried below grade, and usually do not have significant visual impacts on the site. Incinerating toilets may not be desirable to some residents, for varying reasons. The ash residuals must be periodically removed from these units. Some odors may occur from the incineration process. Paper liners must be replaced for each use.