- Damage to the septic tank can cause a blocked soakaway. This is because only some of the waste water should leave the tank and head into the soakaway system. The rest (the lumpier stuff!) should stay in the tank until its regular empty. If the tank is damaged, sometimes the wrong stuff can escape into the soakaway and can block it up. The types of damage to a septic tank which often cause soakaway problems include:
- A collapsed baffle within the tank
- Damage to dip pipes within the tank
- Damage to the structure of the tank, which allows ground water to pour in to it
Once the wrong type of waste has entered the soakaway system, unfortunately it typically can’t be fixed. This is because the pipe work has become blocked, and all the surrounding soil has been polluted by the more solid waste. If this has happened, you might find that either the septic tank appears to need emptying more frequently, or that the untreated waste water makes its way to the surface above the soakaway. This can be pretty unpleasant and is probably not the water feature you had in mind for your garden!
- The wrong ground conditions – we’ve all heard about the wrong kind of leaves on train tracks, but if your soakaway hasn’t been installed in the right type of ground, it might quickly back up. It’s all to do with the need to have sufficient gaps between the soil particles, and certain types of soil – such as clay – just aren’t suitable.
- The soakaway system being overloaded – soakaway systems are only designed to cope with a specific volume of waste per day, and an overload (for example rainwater) can cause problems.
- Damage from tree roots – the roots surrounding trees and shrubs can cause soakaway problems as this can lead to root ingress which would damage the pipe work and block the soakaway system up. Here are some pictures so you can see for yourself!
- Vehicle or machinery damage – this is because the soil surrounding the soakaway pipework can become compacted, reducing the gaps between the soil particles. This in turn prevents the waste water from being able to percolate through them. Soakaway damage caused by machinery can be a common problem for properties whose soakaway system is located on neighbouring farmland.
- The wrong depth below ground – the depth at which soakaway pipework has been installed is really important. If it is installed at the incorrect depth it can cause real soakaway problems. A soakaway needs to be installed at a depth where aerobic bacteria are found within the soil. Any deeper than this, and the bacteria found tends to be anaerobic and may produce a nasty black slimy substance. This can block the soakaway and isn’t good for the surrounding soil.
- High sodium levels – this is a bit techy but high sodium levels in the soil around a soakaway can cause clay particles to build up, creating a waterproof layer around the system. This stops the waste water from being able to pass into the soil.
Will the soakaway drainage problems at my property be covered by my buildings insurance?
Most buildings insurance policies provide some cover for soakaway problems. Typically, policies will cover damage such as tree root ingress, vehicle damage or damage to a soakaway caused by a septic tank problem. Our team is very experienced in managing insurance claims for soakaway drainage problems, and can give you a free assessment as to whether your existing policy would provide cover for the costs to fix the problems at your property. If your insurance policy does provide cover for your property’s soakaway drainage problems, we can manage everything on your behalf. Authorised and regulated by the Financial Conduct Authority, we are the only UK specialists in managing insurance claims for off mains drainage systems – soakaways, septic tanks, sewage treatment plants and cesspits. There is no cost to our customers for us to manage a claim on their behalf, so call our team today on 0800 028 9903 to find out if we can help.
Other solutions to soakaway problems
Solutions to soakaway drainage problems can vary, and should be tailored to the property affected. Unfortunately, it’s not usually possible to repair a soakaway system. This is because of the type of pipework that is used in soakaways, and also because often when a soakaway system is damaged the ground around it becomes polluted, which can’t be reversed. This also means that it is not usually possible to replace a soakaway system where it is currently located.
A percolation test is crucial in understanding whether the ground at your property is suitable for a new soakaway drainage system to be installed. You can find out more about what a percolation test is and why it’s so important in our article here.
If you have the room available, and if the percolation test results are right, you might be able to locate a new soakaway system elsewhere in your garden. However, if a percolation test shows that the ground conditions at your property are not suitable for a new soakaway to be installed, there may be other options available:
- The installation of a sewage treatment plant with an outlet pipe running to a local watercourse – the quality of waste water produced by a sewage treatment plant is greater to that produced by a septic tank. It is therefore possible to discharge the waste from a sewage treatment plant directly to a watercourse (please note that it is not legal to discharge waste from a septic tank directly to a watercourse).
- Sometimes, the type of soil at a property means that the percolation through the soil needs to take place at a much deeper level than a typical soakaway allows. In these situations, a deep borehole soakaway can be used in which a deep bored liner is used. These are not always appropriate though and you should always check with the Environment Agency as to whether they have any specific requirements. If you’re not sure about this, please call our team as we can look after everything for you.
If you are concerned that you have soakaway problems at your property, please contact our team at UKDP on 0800 028 9903 for advice.