Signs of Septic System Failure

Man and women looking at soggy grass which may indicate a failing septic system.

Like most components of your home, septic systems require routine maintenance. If maintained, the septic system should provide reliable service for many years. If the septic system isn't maintained, owners run the risk of dangerous and costly failures. And septic systems do have an operational lifetime and will eventually need to be replaced.

A failed or malfunctioning septic system is a risk to human and animal health and can pollute the environment. A responsible septic owner is alert to the signs of failure, regardless of the age of the system, and responds quickly when any are discovered. A quick response may save the owner money in repairs and may prevent illness and negative impact on the environment.

What happens when a septic system fails?

A septic system failure causes untreated sewage to be released and transported to where it shouldn't be. This may cause sewage to come to the surface of the ground around the tank or the drainfield or to back up in pipes in the building. The sewage could also find its way into groundwater, surface water, or marine water without us ever seeing it. The sewage carries pathogens and other dangerous contaminants. Exposure to these pathogens and contaminants can make people and animals sick. They can also contaminate water sources and make them unsafe for drinking, swimming, shellfish harvesting, and agricultural uses.

What are some common reasons a septic system doesn't work properly?

Pipe from the house to the tank is clogged. When this happens, drains drain very slowly (perhaps slower on lower levels of the building) or stop draining completely. This is often an easy problem to fix. Usually, a service provider can "snake the line" and get it unclogged. You can prevent a clogged line by flushing only human waste and toilet paper down the drain and having your system inspected annually. Sometimes this pipe gets crushed or broken by vehicle or animal traffic. Plant roots sometimes block the pipe (particularly on older systems). Fixing a crushed or root damaged pipe will require replacing (at least) a portion of the pipe.

Inlet baffle to tank is blocked. This failure is very similar to when the inlet pipe from the house to the tank is clogged. If you have access to your inlet baffle opening, you can check to see if there is a clog. If you see toilet paper and other debris, you can try unclogging it using a pole. Be mindful not to damage any of the septic systems components. A service professional can also be contacted for this relatively easy and low-cost fix. Prevent your inlet baffle from getting clogged by only flushing human waste and toilet paper and having your system inspected annually.

Outlet baffle or effluent filter is clogged. This may result in sewage backing up into the home, or possibly surfacing near the septic tank. This issue may be a sign that the tank is receiving too much water, possibly in a short amount of time. If there is an effluent filter this must be cleaned off or replaced. If there is not an effluent filter, fixing this issue will probably require getting the tank pumped to identify and remove the clog. Prevent this type of issue by cleaning your effluent filter (if you have one) and having your system inspected annually.

Drainfield has failed. When the drainfield fails, or is saturated with water, sewage may backup into the home. Wet, soggy areas may develop above or near the drainfield and you may see spongy bright green grass over the area. There may also be odors near the tank or drainfield. This could be the end of life for this component of your septic system. It may be that the system was operated inappropriately and too much solid material made it to the drainfield causing it to fail prematurely. Or, maybe the system worked for many years and simply has no more capacity to accept waste. However, if too much water has saturated the drainfield (through large amounts of water going down the drain or through flood water on the drainfield), it's possible that the drainfield can be dried out and rehabilitated. Contact a service professional to assess the situation. If the drainfield has failed, a connection to the public sewer system should be considered, if it's a possibility. Otherwise, a replacement drainfield will need to be installed.

There are other reasons a septic system can fail or malfunction. If your system isn't working properly, contact a septic professional.

How can I prevent a failure?

Routine maintenance and proper operation will help your septic system have a long and trouble-free life. If your septic system has been properly designed, sited, and installed, the rest is up to you. Inspect your system annually and pump as needed (usually every 3-5 years). Avoid excess water use and watch what you put down the drain and flush down the toilet. Learn more about caring for your septic system.

Can my failing septic system contaminate the water?

Yes, a failing septic system can contaminate well water and nearby waterbodies. Untreated wastewater is a health hazard and can cause many human diseases. Once this untreated wastewater enters the groundwater, you and your neighbor's wells can be contaminated. If the sewage reaches nearby streams or waterbodies, shellfish beds and recreational swimming areas can be contaminated.

Is there financial help for failing systems or repairs?

In some cases, yes. Here's some potential options.


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