Waukesha County


There are numerous commercially available septic tank additives that claim to prevent clogged drains, rejuvenate failing systems or eliminate the need for routine pumping. Septic systems usually fail as a result of old age, neglect or clogged absorption fields, not from impaired bacterial action. Thus, introducing live bacteria or enzymes into a failing system may not offer much help. Additives that claim to clean the septic tank may do more harm than good. Indigestible solids, untreated by the additive, may build up in the tank. The additive may emulsify grease or scum that would otherwise reside longer and be broken down in the tank. These materials could then wash out into the soil absorption field and clog it more quickly.

To prevent damaging your private sewage system, use only those septic tank additives approved by the Wisconsin State Department of Commerce. Department approval means that the manufacturer has demonstrated that the product does not affect soil hydraulic conductivity in the absorption area, or does not affect groundwater quality beneath the private sewage system. Even if Department of Commerce approves the product there is no guarantee that it will work as advertised.

If you are considering using a septic tank additive, please contact the Environmental Health Division at 262-896-8300 to make sure that the additive has been approved by the Department of Commerce and will not harm your sewage disposal system.