Certain residential wastewater treatment systems include reuse of the treated effluent. This is often done through surface irrigation of the waste onto lawns, recapturing the treated water for beneficial use. While properly treated wastewater is safe for discharge to the environment, it may not be safe for contact with humans. There are often pathogenic bacteria and other microbial health concerns associated with treated effluent.
To ensure these organisms are reduced to a level of safe human contact, disinfection devices are often used. The most common is chlorine disinfection, utilizing either of chlorine tablets or liquid chlorine (note - chlorine tablets designed for pool disinfection are not an acceptable alternative to those designed for waste treatment). Usually, an additional tank is installed after the main treatment tank to hold the treated effluent. Prior to entering this tank, or shortly after entering, chlorine is added by the device. Contact with the chlorine during the time the treated effluent is in the tank provides time for disinfection of the microorganisms. The disinfected effluent is then discharged through surface irrigation or disposal to an open ditch or open waterway.
If you are considering the use of such a product, check with your local public health authority to find out what requirements they may have governing the installation and use of chlorine disinfection devices. Some may require that they be certified in accordance with NSF/ANSI Standard 46. For a list of companies and products certified to this standard, please visit our wastewater treatment units online product database.