Pathogens & Your Septic System: Is Your Groundwater Safe?

Pathogens in your Septic System

The Ohio Department of Health estimates there are more than a million households in Ohio that depend on septic systems to treat wastewater. In 2015, the ODH estimated that 31% of them were failing to some degree. Regulations to further protect Ohioans from septic failure have gone into effect since 2015, but many homeowners still wonder what pathogens may be present in their septic system and how they can know their groundwater is safe to drink. Understanding what pathogens are potentially present in your septic system, as well as how your system works to eliminate them and purify your wastewater, will help septic owners know whether their groundwater is contaminated.

What Pathogens May Be Present in Your Septic System

What Pathogens may be present in your septic system

Septic systems have been identified as the largest contributor to groundwater contamination in the US. Any pathogens transmitted by human waste may be present in a septic system if the inhabitants of the home are afflicted with such illnesses. However, the treatment wastewater undergoes in a properly installed and functioning septic system ensures any potential pathogens are eliminated.

Pathogenic Bacteria Potentially Found in Septic Systems

Three types of bacteria always present in a septic tank to some degree are aerobic bacteria, anaerobic bacteria, and fecal coliforms. Aerobic bacteria need oxygen to survive, so they are often prevalent in septic systems with aerators. Smaller than their aerobic counterparts, anaerobic bacteria are less efficient at breaking down solids, but they do not require oxygen to survive and are more resistant to environmental changes. Fecal coliforms are present in the intestines of every warm-blooded animal. They aid in digestion and are not typically carriers of disease. However, they are considered indicator bacteria. If found in a test sample of water, they indicate pathogenic bacteria, like those that cause typhoid, salmonella, and cholera, may also be present.

Viruses and Septic Systems

Viruses depend on their hosts – humans, animals, or certain kinds of bacteria – for their survival. Viruses do not reproduce, like bacteria does, outside of their host, which means the only viruses present in a septic tank are those that were flushed there and managed to survive. However, the hostile pH of wastewater makes it very difficult for most viruses to live for long in a septic tank. Some viruses, like those that cause polio and Hepatitis A, can be present in wastewater. Due to how highly infectious it is, many have investigated whether COVID-19 can be transmitted by human waste. While RNA fragments of the virus have been detected in the fecal matter of infected humans, there have been zero reported cases of faecal-oral transmission of the illness. The EPA believes a properly maintained septic systems will eliminate COVID-19 as efficiently as they do other viruses found in wastewater.

How Septic Systems Eliminate Pathogens

Septic systems, though simple in design, work efficiently to purify wastewater from your home, including eliminating any pathogens that may be present. Once flushed from your home, wastewater first finds its way to the septic tank, where solids settle to the bottom to form sludge while grease and oil float to the top to form a layer of scum. The greywater between these two layers, called effluent, flows out of the tank and into a secondary treatment system, often a drainfield. A system of shallow, perforated pipes sitting atop porous material and sedimentary layers, the drainfield filters miniscule solids from the effluent. Once the effluent has trickled past the drainfield, it enters the soil, where any remaining pathogens are naturally removed as the water filters through the layers of the unsaturated zone before joining the groundwater.

How Pathogens Can Contaminate the Groundwater

Pathogens from septic systems can contaminate groundwater when either the septic system fails or due to improper installation. Septic systems typically fail when they become overwhelmed by the solids and/or the greywater in the septic tank. This happens due to overuse or flushing “no flush” items into the system. When the tank becomes overfull, the contents will either flow back into your home or out into the drainfield. When solids flow into the drainfield, it can become completely clogged and prevent effluent from filtering down through the secondary treatment system to eliminate toxins and pathogens. We call this catastrophic system failure. In a catastrophic failure, potentially contaminated effluent is allowed to pool on the surface above the drainfield. It will eventually find its way to streams, contaminating any downstream groundwater with whatever pathogens are present. This type of groundwater contamination can be prevented by properly maintaining your septic system. Scheduling regular service visits will ensure your tank does not become overwhelmed and that any damaged equipment is repaired before it becomes a problem. Proper maintenance also includes conserving water usage wherever you can and being very careful to avoid flushing the wrong things into your septic system.

Groundwater contamination due to improper septic installation is much more difficult a problem to remedy. Septic regulations stipulate where the septic tank and drainfield can be installed in relation to any source of drinking water or nearby streams. If installed too close to the home’s drinking water source, a properly functioning septic system may be able to contaminate the drinking water. Similarly, if the drainfield is installed too close to a nearby stream, the effluent may be able to reach the stream before all toxins and pathogens have been removed. If you are not certain whether your system has been properly installed, according to current regulations, you should schedule an inspection immediately to ensure your home’s water is safe to drink.

Supeck Septic Services is a family-owned and operated, registered septic service provider serving all of Northeast Ohio. We have been providing stellar service to our community for the past 52 years and are proud to now be recognized as the largest septic provider in Northeast Ohio. Contact us today to schedule a service visit or inspection!

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