7 Common Causes of a Blocked Drain

From nappies and children’s toys, to toothbrushes and Yellow Pages advertisements, we have seen it all when it comes to blocked drains. Presenting in a range of different ways such as a gurgling drain or a sewer overflow, they are a frustrating and often messy problem to have.

This list covers the 7 most common causes of blocked drains, some are avoidable and others are unfortunately not.


As much as a lush garden and trees may look visually appealing, the roots that grow and spread deep below the ground can be your sewer’s worst nightmare. They will make every effort to find water underground which often results in them entering your sewer or stormwater systems through even the slightest of cracks or separated joins. The roots will then thrive off the moisture in the drain and grow into a tangled web that can cause serious and recurring issues.


A broken pipe may go unnoticed for a long period of time, however, if it eventuates into a completely collapsed pipe it can often lead to an emergency repair. The dreaded tree root can be one cause of a broken pipe, along with ground movement, structural issues or additional load from above ground. Not all broken drains will need to be excavated, we offer a no dig solution with our pipe relining service.


Marketing of flushable wipes can be extremely deceiving, given that there actually are no safe ‘wet wipes’ that should be used in your sewer system. In fact, Sydney Water reported that 75% of sewer blockages involve flushed wet wipes, and if you are lucky enough for them to clear through your own properties sewer system, they will often end up overflowing into local waterways or other homes. If you are a common user of wipes, whether they are labelled flushable or not, your safest option is to dispose of them in a bin rather than your toilet.


Although not marketed in the same way as wipes, female hygiene products seem to be flushed down the line just as often. No matter how new or improved your sewer system may be, sanitary products should always be disposed of in the bin rather than in the toilet as they will often get caught in the line (not to mention the environmental impact or damage to the wastewater system!).


Hair and soap scum blockages are most often found in shower, bath and basin drains. Some people may be surprised at just how much hair can be washed down the drain, this coupled with detergents and soaps can lead to a hair and soap scum build up on the edges of the drains. This significantly reduces the diameter of pipes and in turn, results in blocked drains.


The biggest culprit in kitchen drains are oils and grease that are washed down the sink. No matter how careful you are at removing all fats from dishes prior to washing, there is still a small amount that will end up in your drain and can solidify inside the pipes. This can especially occur in the tight S bends of pipework or in flat sections of drainage. Any food scraps that are washed down the sink contribute further to this as they get stuck on the grease build ups.


Although all items previously mentioned in this blog can be regarded as ‘foreign objects’, there are many other obscure items that find their way into drains. Products such as tooth picks, cotton buds, bobby pins, toilet sanitisers and even kids toys may accidentally fall into drains at times. If they then run into any of the above issues within the pipe, such as tree roots or cracked pipes, they can be very hard to remove. If you do happen to drop something into a drain, it should be removed immediately rather than trying to flush it away.

The cause of some blockages may be obvious, however, others can be hard to identify. A qualified and experienced plumber should be able to efficiently diagnose and repair your blocked drain issue.

We at Nuflow Newcastle offer blocked drain clearing and camera inspections to investigate any potential issues you may encounter. Once identified, we will provide an honest and upfront quote for the best method of drain repair. Depending on the location of the issue, the course of action may involve excavation works, pipe relining or a combination of both.

If you feel that you are having difficulties with your drainage systems, get in touch with Nuflow Newcastle on 02 4943 9000 to see how we can help out!

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