Does my septic tank need replacing?

If you have unexplained drainage or sewage issues in your home, you’ll be relieved to know that you won’t necessarily have to turn your home inside out looking for the cause of the problem. 

Unpleasant odours, slow drains, pooling water and sewage backups can be resolved by something as simple as replacing your septic tank. 

Septic tanks have a lifespan. While they can last up to 40 years, they need replacing when they start to show signs of deterioration.

The plumbing experts at UKOOA have created this guide to help you identify whether your septic tank needs repairing or replacing and what to do if you find any issues with your plumbing system. 

What are septic tanks and how do they work?

A septic tank’s job is to safely remove sewage and wastewater from your home. It does this by separating the solids and liquids within the sewage or wastewater. 

Most septic tanks are made up of two separate chambers. Wastewater and sewage enter the first chamber, where they stay until the solid stuff separates from the liquid. Scum—which consists of fat and grease—moves up to the top of the tank to form its own layer, while solids fall to the bottom of the tank, making up a layer of ‘sludge.’ 

The liquids then move through into chamber two, where they are safely discharged into the drainage field. 

Most of the time, this system works pretty well. However, after a few years, your septic tank may become broken or damaged. This can lead to leaks, backups, blockages and improper drainage. 

Here are some telltale signs that something’s up with your septic tank. 

Unpleasant odours

It goes without saying that septic tanks aren’t exactly going to smell like a bunch of roses. Even so, you should not be dealing with any unpleasant odours anywhere outside of the main chamber lid. This means that if you’re getting a whiff of something nasty in your bathrooms or kitchen, it could be time to contact our plumbing team

When your septic tank starts emitting nasty smells throughout your home, it’s probably because the waste isn’t being processed properly, leading to old waste building up and creating a foul odour.

Equally, bad smells emitting through your home could be caused by blockages if someone has been flushing things down the toilet that they shouldn’t be. Items like wipes and sanitary towels are not supposed to enter your drainage system and can wreak havoc on your septic tank’s ability to work effectively. 

While you can pay for your septic tank to be pumped, this should only need to happen every two to five years. So, if you find you need to flush out the tank more often, it could be time to replace the tank altogether. This will also save money and hassle in the long run. 

Slow drains

Sluggish and slow draining of water from places like showers, sinks and baths is another telltale sign that something isn’t right with your septic system. 

Blockages that are causing drainage issues to and from your septic tank don’t always mean a replacement is necessary. It could mean that the issue needs repairing by unblocking the drain or pumping the tank. However, it’s always worth contacting a licensed plumber to get their opinion on whether the blockages are caused by your septic tank deteriorating, or something else. 

If you’re having frequent issues with slow drains, chances are it might be time for a new tank. 

Sewage backups

One of the most disgusting and hazardous issues that can happen with a septic tank is the backing up of sewage in and around your home. This is likely to indicate a serious septic tank issue.

If you do notice sewage backing up on your property, then don’t delay in calling a plumber. Aside from looking and smelling awful, having raw sewage out in the open is a massive health hazard, and you should get in touch with an emergency plumber immediately. Just some of the germs that can be present in sewage include Salmonella, E.coli, Streptococcus and countless others. 

Pooling water

Pooling water is another sign that you have a septic tank problem. If you’re noticing pools of water cropping up on your lawn, this could be due to your septic tank having damage to its walls, base or pipes. It could also happen because there’s an issue with the drainage field, meaning that wastewater is returning to the tank and causing it to fill up too quickly. 

Either way, it’s definitely worth calling an expert to come in and take a look, so they can identify the cause and the best course of action to take. 

What to do if your septic tank needs replacing

Whether you’re dealing with non-urgent issues like slightly sluggish drains, or you’ve found yourself with something more serious such as sewage backups, it’s best to call in a plumber as soon as possible. 


Even if the septic tank issue you’re facing doesn’t seem urgent, ignoring the problem can lead to more serious damage further down the line. To save yourself both money and a headache, just get in touch with our team of friendly professionals who will be happy to talk you through your options.