Septic Tank Full Of Water Not Draining (How To Fix)

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By Bryan Peters

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Septic tank full of water but not draining is one issue septic tank owners dread due to the complications and inconveniences involved.

This is why we would not just be looking at how to fix the problem alone but will also give you tips on how you can avoid it altogether.

We believe that knowing what causes it will help you prevent a reoccurrence of draining problems due to your full septic tank.

Septic Tank Full Of Water Not Draining: How To Fix It

The issue is much more complicated than it looks. We’ll explain why.

What causes your septic tank to get filled with water and not drain well are mostly clogs in the drain pipes or the septic tank itself or any form of damage to the septic tank

Now, these issues are not something a layman can just handle without prior experience. They need to be checked out by a professional. There are other times that your septic tank may get full that you would not have to worry about. 

When there’s heavy rainfall, for instance, your septic tank could get full. This does not call for fear as the water will disappear like it was never there, absorbed straight into the ground. If all goes well, it should be resolved within days.

All the same, when your septic tank gets too full and does not drain well, it would be wise to check it out and confirm that it is not a result of rainwater.

If it isn’t, contact a septic tank expert at once.

Why Does My Septic Tank Get Filled With Water?

Your septic tank getting filled up with water is days away from being an emergency.

We think that knowing what we do exactly that fills it up with water, we might be able to avert a reoccurrence.

Find some of the reasons below.

1. Septic System Is Damaged Somewhere

The septic tank is a very delicate material and we always advocate for only experts to maintain and handle it in general. This is to avoid any form of damage in the septic system.

Talking about damages, maybe in form of cracks or an outright breaking of a part of the septic system. All these issues affect the septic tank and cause it to drain inefficiently.

A crack would allow for wastewater to seep out of the tank and groundwater to seep in. In no time, your tank fills up very fast and you’ll start experiencing drainage issues. If your drain field pipe is cracked or broken, chances are that your septic tank will fill up with water in no time.

If you are wondering, a drain field is a wastewater disposal facility found on the sub-surface that serves the purpose of expunging impurities from the liquid. 

How does it work?

Ideally, water from the septic tank flows through a pipe on the outlet straight into the drain field.

Damages to this highly sensitive material can be in form of cracks, holes,s or even clogs in the outlet, thereby obstructing the flow of liquid. 

Most people have also attributed the main problems with the drain field to Tree roots. The effects of tree roots include taking away the pipes and impeding the flow of water in the process.

2. Using Excess Water

The problem is not really with using too much water but using too much water in quick succession. A septic tank ideally, is built up just for normal usage of water with the size of your house in consideration.

This means that if your septic tank is filling up with wastewater very fast, there is a high chance that it will soon be too full of water and proper drainage would soon be a problem for it.

3. Materials That Are Unsafe For Septic Use, Flushed Down The Drains

This is one area that a lot of people need to pay attention to. Unsafe materials being flushed down the drain is one of the major factors that cause the build-up of water in the septic tank and subsequent drainage issues.

What do we mean by unsafe materials?

We are simply referring too to materials that do not break down easily in the septic tank. 

Items like sanitary pads, paper towels, diapers, and the like are all unsafe for your septic tank. Habitual flushing down of these items will likely result in a clog in the pipes.

Even too many wads of toilet paper flushed down will cause a clog as it will be too difficult for it to disintegrate in the septic tanks.

Most times, it already causes the clog in the drain pipes before even getting to the septic tank itself.

Other items that may not necessarily cause a clog but damage the septic tank or in your drainpipes or septic tank include chemicals and FOGs – Fats, oi,l, and grease.

4. Leakages

Leakage is another known culprit for making septic tanks fill up with water very fast. 

So, when next your septic tank fills up with water, leakage is a high possibility that you should look out for.

Areas likely to leak are faucets and pipes. Water may be leaking from them down the drain and finally the septic tank.

How To Know Your Septic Tank Is Full

The most reliable sign happens to be slow draining. Other signs include:

  1. Offensive odor around the drain field
  2. Standing water in different areas around your drain field
  3. Sewage backup through the pipes
  4. Gurgling sounds emanated from the drains
  5. Finally, the  Septic tank alarm sounded. This is optional though as not every septic tank has this useful feature that sounds like a warning when the water level within it is getting high

How To Avoid Water Getting Into Septic Tanks

Top on our list is constant maintenance. Maintaining a clean septic tank and seeing to its servicing as at when due will help in no small measure.

Other care practices that you can imbibe are:

  • Flushing only septic-safe materials down the drains
  • Avoid as much as possible, the use of harsh chemicals in the septic tank
  • Planting around the drain field will help in absorbing to a large extent, the water that leaves the septic tank
  • Limit as much as possible, the use of water
  • Have gutters in strategic positions that would keep excess water from them away from where the septic tank is located
  • Keep your septic tank clean by being mindful of when and how you carry out any dirty work around it
  • Maintain clean and clear gutters so there won’t be any standing water


We’ll like to reiterate once again that the best way to avoid your septic tank from getting too full and developing drainage problems is proper maintenance. 

You should follow through with maintenance as doing so is a lot cheaper than a plumber’s fees.

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