One in four people in the US have an onsite or individual septic system to treat wastewater.
What happens to wastewater when it leaves your house? Is just "going away" enough? No it is not! Wastewater is part of the water cycle, entering the house clean, being used, then being cleaned for the next use. We don’t get new water – we must clean and reuse what is here.
To ensure your system is working – not just sending the water away, you need to understand the treatment plant buried in the backyard. Individual septic systems work on the same principle as large municipal treatment plants, just on a much smaller scale.
Well maintained and functioning septic systems do an excellent job removing bacteria and other harmful pathogens from our wastewater, returning clean water to the groundwater system. However, no municipal or individual system can effectively remove medications or drugs from wastewater. Therefore, precautions should be considered.
Effects of Drugs and Medications on a Septic System
Medications – both excess prescription and over the counter drugs, and excess medications eliminated by the body cause problems in individual septic systems. Take care when disposing of medications to protect the septic system.
High concentrations of antibiotics or chemicals can kill or retard the growth of the bacteria in septic tanks and in the soil treatment drainfield or mound. If the tank bacteria are destroyed, solids accumulate in the tank much faster and can create problems in the soil treatment area.
Chemotherapy drugs, extended use of strong antibiotics and other strong drugs can be harmful to a septic system. These drugs are designed to kill bacteria in the body, they also kill good bacteria needed to treat the wastewater in a septic system.
Most drug problems in septics result from consumed drugs. The human body only uses a portion of the drug, some is eliminated in body waste before it can be absorbed by the body.
Managing a Septic System Exposed to High Concentrations of Medications and Drugs
If someone in the household is on chemotherapy, it is recommended to have the septic tank pumped at least twice a year during the regimen. This is also true for someone on an extended program of strong antibiotics. A child taking a mild antibiotic for 10 days for an ear infection is not cause for concern with a septic. Rather, an adult taking strong doses for a month or more.
Fill the septic tank with clean water after pumping to dilute the concentrations of the medicines. This will keep the system from stressing when it restarts after pumping.
If the use of strong medications is extended, it may be necessary to use the septic tank as a holding tank. This prevents the drugs from reaching the drainfield and thus the groundwater.
Consider adding an effluent screen to the outlet pipe of the tank. Consult with a local septic professional for advice. The screen will catch more solids trying to leave the tank. If chemotherapy drugs are the situation, the screen will catch hair during the hair loss phase of treatment. Effluent screens will help keep solids from entering the drainfield and plugging the system.
Limit the use of bleach and antibacterial soaps and cleaners and bleach, to limit stressing the tank bacteria.
Dispose of Extra and Expired Medications Safely
Cleaning the medicine cabinet, and find expired medications? Take care to protect personal privacy, prevent theft and protect water quality. Do not dump extra medications into the toilet.
- First, check with the pharmacy. Many now take extra drugs back. If that is not an option, dispose of them safely as follows.
- Remove all product labels to protect privacy. If the label is difficult to remove, either use a heavy black permanent marker, or try soaking the bottle in water.
- Liquid drugs – add kitty litter, soil, flour, cornstarch, anything that will absorb the liquid. Make sure the lid is on tightly.
- Pills – add liquid cleansers, vinegar, lemon juice or water to dissolve the pills. Acids like vinegar will ensure the pills dissolve. Be sure the cap is on securely.
- The destroyed pills or liquid medications can now be safely put in the trash. For added protection, put them in a zip-lock food storage bag. Put the bag in an opaque container such as a coffee can with lid, empty yogurt container, or anything that hides the bottle from view.
For more information, see "Medications and Your Septic System" from the University of MInnesota Extension website.
Understand Septic System to Ensure Treating Wastewater
Homeowners who understand and maintain septic systems help ensure a clean drinking water supply. Review these articles for more tips and help. Individual Septic Systems: Water, Product Use, Maintenance for Individual Septic Systems, Landscaping Septic System Drainfields and Mounds.
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Valerie Prax - Valerie Prax recently retired after nearly 35 years with University of Minnesota Extension. She served as an Educator and Professor for 27 ...
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