What are typical problems with a septic tank?

Posted by Callum Vallance-Poole, on March 7, 2022.

Graf UK Carat Septic Tank

Septic tanks are usually out of sight and out of mind – until there’s a problem that needs to be fixed. That’s why it’s helpful to know about the typical problems owners have with a septic tank, so you be prepared and resolve them as quickly as possible. Here are some of the most common you need to be aware of.

Tree or plant root damage

Because septic tanks are installed below the surface, you never know when tree or plant roots could start to grow and interfere with system. Roots are incredibly strong and persistent and if left to grow can even push through tank walls or house-connected pipes. This could lead to liquid leaking from the tank out into the ground. When installing a septic tank, you can take some precautions by not placing it too close to trees or shrubbery, which will reduce the chances of the system being damaged.

Poor maintenance

This is probably the most common problem faced by septic tank owners. There is sometimes a misconception that once it has been installed it can be left to its own devices, but it should be emptied regularly to avoid any problems with the system. The schedule you need to follow will vary depending on tank size and usage levels, but this is something that should be planned during the installation. To keep the tank is good condition it should be emptied on a frequent basis, and you will be able to hire a local, professional company who can help you with this process.

Ground movement

You probably won’t ever notice it, but the ground around your septic tank can move, and even the smallest shift can create problems for the system. If more pressure is placed onto the tank it could lead to fractures and cracks appearing on the walls. This may create openings that allows groundwater through the cracks and the system will subsequently struggle to separate liquid and wastewater. Even if it doesn’t reach this stage, it could mean you have to empty the tank more regularly, or even be forced to buy a replacement.

Broken dip pipe

Some septic tanks will feature either a dip pipe or baffle, or sometimes both, depending on the style of tank you have installed. Dip pipes work in the same way as a baffle, making sure the correct type of waste can flow into the system. Sometimes, the dip pipe can be knocked off when the tank is being emptied and left unnoticed at the bottom. This is an important one to keep an eye on, as if the wrong waste is being filtered it could end up going back into your own home and causing a host of other problems.

Poor installation

Septic tanks are best installed by professionals who have experience with the task and understand the full range of issues that need to be managed. A poorly installed septic tank can create a lot of problems that are often costly to repair, so it pays to use a reputable company and not base your decision purely on cost. Installers must carry out a percolation test to check that the ground is suitable for a soakaway and to measure the size and depth. The process must also meet current British Standards and Environmental Agency regulations, which an experienced company will be aware of. A system that doesn’t comply with legal requirements could leave you open to prosecution and a large fine.

Vehicle damage

As we mentioned above when talking about ground movement, any large, unexpected weight placed onto your septic tank can cause damage. Septic tanks are stored underground, which means unless you are aware of the installation it’s almost impossible to know its location. If a vehicle drives over it or parks above the tank, this will create extra pressure that it could struggle to cope with. The best way around this is to use clear markings that indicate where the tank is positioned so others can avoid it and help you keep the tank in good condition.

Damaged baffle

The baffle is a barrier inside the tank that is there to prevent any lumpy material getting into the septic tank. It’s an essential part of the tank design that needs to be in good working order for the filtration system to operate properly – without it wastage (effluent) can easily get into the soakaway system and create a blockage. With the system blocked up it can back up through the system into your home, or it could start to work its way up to ground level and pool on the surface. Given the nature of the waste, this is something you really want to avoid happening.

Hydrostatic pressure

This is not something that happens very often, but it is still a possibility. If the tank is experiencing too much pressure from water below the ground it can force the tank to quite literally ‘pop’ up out of the ground. Should this happen, there is a good chance that the pipe connected to the tank will become detached, which causes the system to back up, which often has a direct affect on your home. While this is not a common occurrence, if this does happen it will need to be fixed as soon as possible by a professional company.

Worn down tanks

Over time, everything begins to show signs of wear and tear and septic tanks are no different. Some tanks remain in good working order after decades of installation, providing they are well maintained and managed. Older tanks may not have the same features as modern-day varieties, some featuring dip pipes and containing a single chamber rather than a double. While there is no limit on how long soakaway system are expected to last, at some point it will need to be replaced, and if you have an old tank installed, investing in a new one may prove to be more cost effective in the long run.

Marketing Coordinator - Based at our UK HQ in Banbury, Oxfordshire, Callum is responsible for promoting Water Management Systems, Attenuation Tanks, Treatment Plants, Rainwater Harvesting Systems and more!