Symptoms of a Failing Septic System

If you have a failing septic system, there are usually a few indications of this happening that you may or may not pick up on. Sometimes things are obvious like backed-up drains and a foul smell. Other times these things are not so obvious to the uninitiated. Notice especially lush grass growth near the site of your septic tank.

Photo of a home's yard where the septic system lives

This article looks at a few of the symptoms you may notice if you have a failing septic system.

Indoor Drain Issues

If the septic problem is particularly serious, you’ll notice signs of it in your home. This can manifest as decreased flushing in your toilets, decreased drain flow, and unpleasant odors in your home. If the drains in your house are taking forever to drain, that’s a good sign that you have an issue with your septic system.

In really severe cases you will notice a backup of sewage in your drains or toilet which is often black and smells pretty unpleasant. You may also notice gurgling sounds in your plumbing system, which are another tell-tale sign of septic issues.

A great way to try and prevent these issues, beyond flushing only appropriate items down drains, is to use a pressure transducer to monitor the level of fluid in your tank. This way you will be notified before the problem becomes larger and inevitably more expensive.

Near the Tank Itself

Even if everything in your house is fine, you might still have a problem with the septic system. Is there an odor around your septic tank or drain fields? We could be looking at a problem.

Another obvious sign is standing water around your septic tank or the drain fields. This can manifest itself as a lush, bright green, and a spongy patch of grass over the septic tank or drain fields, which thrives even in dry weather. This is an obvious sign that sewage is leaking and effectively fertilizing this patch of lawn.

Not as Easy to Notice

In addition to these signs, there are a few less obvious ones that you may not directly link to a problem with your septic system. If there’s a presence of contamination with either nitrates or bacteria in your well water, it’s a clear sign of something wrong with your septic system. This should be rectified quickly because it is a major health hazard to you and your family.

Another potential sign of a failing septic system is algal blooms and an abundance of aquatic weeds in nearby ponds. This results in these areas because they are being fertilized by sewage as a result of a septic leak.


There are a few common reasons why septic systems fail. Some of these can be easily rectified whilst others may need significant intervention and investment to deal with.

If your drains are draining very slowly, this is a sign that the sewage pipe coming from the house and leading to the septic tank is clogged. That’s generally simple to fix. Simply call a septic cleaning service and have them “snake” the line to remove the blockage. This can be prevented by making sure that you only flush sewage down the commode.

A similar problem can arise when the tank’s inlet baffle is clogged. It’s theoretically possible to unclog it yourself if you have access to the piping. Otherwise, call a professional.

If there’s sewage backing up into your home or surfacing near your septic tank, then the issue could be either the outlet baffle or the effluent filter being clogged. This problem is a sign that the tank is receiving too much water, perhaps too much too fast. The effluent filter may need to be cleaned or replaced. You may even need to have your septic tank pumped.

If your drain fields fail or become saturated with water, sewage may back up into your home and soggy areas may appear over the drain fields themselves. There might also be odors around the drain fields or tank in this case. This is often a sign that your drain fields have reached the end of their usable life.

Sometimes though, it’s simply an issue of too much water saturating the drain fields, which can often be drained and rehabilitated.


If you’re experiencing any issues with your septic system, it’s vital to call in a professional to evaluate the situation. There’s simply no way you will be able to figure out what’s wrong with your septic system until they snake the line.

Serious issues aren’t a DIY job. You could search septic tank service near me to find an expert who can properly evaluate and rectify the situation.