The purpose of this publication is to describe on-site technologies for treating domestic sewage where conventional means (public sewer or septic tank with drainfield) are not available. These technologies are described as alternatives in this publication. Our goal is to provide information that can be used by property owners and residents to initiate action to rectify sewage-disposal problems, especially where current wastewater treatment is inadequate. This work is intended to provide information on alternative wastewater treatment options that will help the reader to make informed decisions when dealing with oversight agencies and contractors; it is not intended to serve as a stand-alone reference for design or construction.

Household wastewater contains some contaminants that degrade water quality for such uses as drinking, stock watering, food preparation and cleaning. Potential contaminants in household wastewater include disease-causing bacteria, infectious viruses, household chemicals, and nutrients, such as nitrate. Viruses can infect the liver, causing hepatitis or infect the lining of the intestine, causing gastroenteritis (vomiting and diarrhea). If coliform organisms (a group of indicator bacteria) are found in well water, they show that the water is potentially dangerous for drinking and food preparation. Virtually all farmsteads use a septic system or similar on-site wastewater treatment system.