4 Common Septic System Problems and How to Avoid Them

A septic system is essentially a large holding tank designed to hold human biological waste material until natural bacterial action breaks it down into three components – gases, water (mixed with some components that aren’t consumed by bacterial action), and solids. Over time, the gases and water are eliminated from the tank into the immediate environments (the gas through vents and the liquids through tubes extending out into a distribution field), while the solids sink to the bottom and must be periodically removed from the tank by pumping.

A well-designed septic system dealing only with human biological waste quite likely wouldn’t have any of the problems commonly associated with them. However, biological processes do take time to turn the waste into water and gas and septic systems are commonly asked to handle much more than just human waste.

In most homes, they have to deal with kitchen wastes, lots of water from family baths and showers, plus the output from dishwashers and washing machines (including soaps and detergents), plastics and non biodegradable ‘flushable’ products, and sometimes even things like solvents, paint thinners, or gasoline.

As a result, it’s pretty easy to figure out what causes most common septic system problems: it's us asking them to deal with things they aren’t designed to handle.

Here are the most common issues plaguing septic tanks.

1. Excess water in the Tank

Inefficient water use can cause the tank to hold more water than it was intended. Excess water means the solid wastes don’t get a chance to break down before the water level in the tank raises so high that solid matter passes out of the tank into distribution tubes that are only built to handle liquids, effectively blocking the tubes.

Minimize the amount of water going into your septic system by spreading out clothes washing over a number of days, rather than doing all the family laundry on one day. Shorten the length of showers and use ‘low flow’ showerheads to help keep excess water out of the system. Low flow or dual flush toilets will also minimize water going into the system.

2. Flushing Non-biodegradable Items

Non-biodegradable products in the tank fill up space and will never go away naturally, once again raising the liquid levels in the tank higher and forcing floating solids into the distribution system. Even so-called 'flushable' products don't break down as they should sometimes. It is important to only flush bodily waste and toilet paper—nothing else.

Keep kitchen wastes out the system. This means no oil or grease down the kitchen drain plus, a garburetor shouldn’t be connected to the system (kitchen wastes break down differently than human waste). Keep all non-biodegradable products out of the system. This includes flushable items like tampons, diapers, paper towels even cigarette butts.

3. Using Too Much Detergent

Phosphates from detergents act as fertilizer encouraging algae growth that can block the perforations in the distribution pipes. If you use too much detergent while doing laundry, there is no guarantee your machine will rinse away all the residue and properly dilute it. Overuse of these products, and more importantly, the wrong products, will be a problem for your pipes and tank.

Use liquid or gel soap in dishwashers and washing machines – gel soaps don’t contain phosphates like powdered soaps.

4. Harsh Chemicals

Chemical products like solvents, pesticides, brake fluid, gasoline, motor oil and paint thinners are toxic, and by putting them into a septic system, they are distributed into the surrounding soil, polluting it and making it unfit for plant growth. Plus, these harsh products will kill off the bacteria in your tank that is necessary to break down waste in the septic system.

Never use your septic system as way to get rid of toxic materials like solvents and paint thinners. They won’t be eliminated, they will simply be distributed into the soil. Commercial products that claim to clear septic systems often contain toxic or hazardous chemicals like lye that are bad for the environment.

Important Tip: Have your system pumped out on a regular basis (experts suggest every two to four years) to ensure the system has enough capacity to work efficiently.