Blog>Expert Advice>Five signs your septic tank needs emptying
Last updated: 6 September 2024
Five signs your septic tank needs emptying
No one wants to be faced with a overflowing septic tank. Learn the telltale signs that your septic tank needs emptying and how much you can expect to pay in this essential guide.
An overflowing septic tank can be unpleasant and costly to deal with. It could also land you in murky waters with your local authorities or the Environment Agency.
Fortunately, the signs that your septic tank needs emptying are simple to spot – if you know what you’re looking for.
Keep reading to learn the five telltale signs that your septic tank needs emptying. We also explain what happens if your tank overflows and how much a waste disposal expert will charge to fix it.
How do you know when your septic tank needs pumping?
Booking routine tank empties with a qualified waste removal expert will keep your septic system running efficiently and safely. If you have the correct tank size, you’ll only need to empty it on average once or twice a year.
However, it’s always a good idea to look for any warning signs that it needs to be emptied sooner. They are:
1. A foul smell
An unpleasant smell from your sink, shower or bath drains could indicate that your septic tank needs to be emptied. The odour is often more obvious at night when there isn’t as much water running.
If you’ve experienced a period of heavy rain or had more guests in your home than usual, the tank may fill quicker than usual.
Either way, you’ll want to investigate, as sometimes a foul odour could mean the septic tank or soakaway (which safely removes wastewater) has become blocked.
2. Sluggish drains and gurgling sounds
Is water draining more slowly from your sinks, baths, or showers? Or have you noticed a gurgling sound as the water drains away? This could indicate that your septic tank is full or the drainage pipes are blocked.
If ignored, it could lead to overflowing. So, it’s best to nip it in the bud immediately with the help of a waste disposal expert.
3. Waste backup
If you notice discoloured water backing up in your showers and sinks, you’ll want it seen to fast by a qualified waste disposal professional or a specialist plumber.
Use minimal water until the issue is solved, and avoid running baths or using the dishwasher. Otherwise, you could make things worse.
4. Low water flow
If you notice a significant drop in water pressure, it might be another sign that your septic tank needs emptying.
Low water flow sometimes means the waste in your septic tank is not moving through the drainage system efficiently and needs looking at by a specialist plumber.
5. Wet, squishy grass
Have you noticed wet, squishy grass, unusually green grass patches, or water puddles near the septic tank? Unfortunately, this could mean your septic tank has overflowed.
A specialist must deal with this immediately, as the ground surrounding the tank and soakaway may have been contaminated by untreated sewage, which can get into your water source. There's more information about that next.
What happens if my septic tank overflows?
Has your septic tank overflowed and contaminated the soakaway or other ground? You'll need a specialistto remove the contaminated soil, which costs around £40/m³.
Sometimes, you may need to wait a few days for the area to dry out before a tradesperson can access it. They will also advise you to avoid using water until the issue has been solved.
While this is not ideal, it could prevent the problem from worsening or you being fined by local authorities. Under current UK legislation, allowing a septic tank to overflow or leak is an offence.
In extreme cases, if your septic tank overflows and pollutes a nearby river or other watercourse, the Environment Agency may also take legal action against you. So, it is vital to take immediate action with the help of a specialist.
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How do you find a septic tank specialist?
Trying to fix a septic tank problem yourself is never a good idea. It could invalidate the warranty on your tank or home insurance cover.
That’s why we always recommend hiring a waste disposal expert to empty your tank or carry out any repairs.
Use our search tool below to find a reputable professional and get a personalised quote.
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How much does it cost to empty a septic tank?
The average cost of emptying a septic tankis between £120 - £350, depending on the tank size.
If you'd like an expert to clean the tank with a chemical treatment at the same time, this will be an additional cost of £200.
Read our septic tank emptying cost guide to get more costs.
Other frequently asked questions
How often should septic tanks be pumped?
The right-sized tank for your home should only need emptying once or twice a year. For larger tanks, this may be even less. You could also consider buying a sludge judge tool to help you monitor the levels of wastewater and waste in your system between routine empties.
Can I empty a septic tank myself?
Under the 2020 regulations, emptying a septic tank is a criminal offence unless you are a qualified waste disposal professional. Therefore, you must always use a qualified professional.
Does a new septic tank require planning permission?
Unless it’s a like-for-like replacement, your new septic tank will need building control permission and consent from the Environment Agency.
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