My septic tank is leaking above ground - what should I do?

Septic tank damage | By Sam Warren

If your property has a septic tank or other off mains drainage system, you'll be hoping for years of trouble free service from it. After all, it's tricky to know what's really going on underground, and you might be blissfully unaware of any trouble brewing....until it surfaces above ground! If you've found us because carrying out a slightly panicked Google search because your septic tank is leaking above ground, then take a few deep breaths, put the kettle on and we'll talk you through what might be causing the problems - and what you can do about it.

Why is my septic tank leaking above ground?

Ok, so let's first look at the basics of how a septic tank works. Waste from your property's toilets, sinks, showers/baths and kitchen appliances all flow through a pipe to your septic tank. Septic tanks come in all different shapes and sizes, and there are both traditional styles and more modern ones - so your septic tank could be made of bricks, or it could be something such as glass reinforced plastic. Either way, all septic tanks perform the same basic function, which is to separate the waste from your property into three layers (see below), and to ensure that only separated waste water leaves the septic tank. The rest stays inside to be removed during a routine empty.

The waste water usually leaves the tank and enters a soakaway system - typically a network of perforated or slotted pipes. The water passes through into the surrounding sub soils, and in doing so it is treated such that it doesn't cause a pollution.

So, if you've noticed boggy patches above your septic tank or soakaway, or murky looking water pooling in your garden, it could be a sign of soakaway problems or septic tank problems. Follow this simple step by step guide to try to work out what is going on:

  • Get the septic tank emptied. Have you missed a routine empty? Most tanks need emptying annually. Or has the tank been used a lot more than usual recently? Having friends or family staying can increase the volume of waste entering the tank. Either way, your first port of call when you notice any possible problems with your drainage system is to get it emptied and see if that sorts things out. Often it will - phew!
  • Ask the tank emptying company if they can spot anything. Typically these chaps (or chapesses) are there simply to empty the tank, but if there is something obvious going on, they may be able to spot it.
  • If emptying the tank doesn’t resolve the problem, you’ll need a septic tank inspection. Unfortunately, if your tank has filled back up again, this will mean needing to get it emptied again. Why is this important? Because there could be damage to the walls or base of the tank itself, and it will only be visible once the tank is empty. A sign of a split in the walls or base of the septic tank might be water spurting in through a hole when the tank is emptied. A septic tank inspection should also look at the pipework in the soakaway system – there could be tree root damage, or perhaps the pipes have collapsed. Either of these things could result in water pouring back into the septic tank, and it leaking above ground.
  • If there are no signs of any damage, it might be that your soakaway system needs replacing. There is much debate around how long soakaway systems should last, but the truth is that there is no one hard and fast rule. This is because there are a huge number of variables affecting this, including the ground conditions, the level of usage of the system, and how often it is emptied. We have seen soakaway systems functioning as they should for decades. If there is no damage to the soakawaway pipework, but a CCTV camera survey shows it to be full of water and/or water is flowing back into the septic tank when it’s emptied, this can be a sign that it’s simply packed up.

So what are my options to sort the septic tank problems out?

A thorough survey will tell you exactly what’s going on, and an off mains expert (such as ourselves of course!) will be able to talk you through your options. If damage has been found, then it’s possible that our team could get the costs of replacing or repairing the system covered by your buildings insurance. You see, we are the only specialists in the UK to focus on off mains drainage and insurance claims – and yes, you are right to assume that we are terribly fascinating people! Find out more about how it all works here and get in touch with our friendly team to chat about how we can help.

If there is no damage, but the soakaway system has stopped working, you may be able to replace the soakaway system, although this will be subject to how much space you have available and the ground conditions.

The team at UKDP are on hand for advice and guidance, so give us a call and chat to us about any septic tank troubles you are having on 0800 028 9903 or 01628 788600. We’ll be happy to help!

0800 028 9903