How To Get Rid Of Drain Flies

Found a swarm of tiny flies hanging around your sink plugs? These will likely be drain flies! These tiny pests are a nuisance and can be a sign of poor drain hygiene due to built-up sludge in drains.

What are drain flies?

Drain flies are tiny little flies measuring from 1.5 to 5mm long. They are attracted to standing water and sludge, which is why they can often be found inside dirty or clogged sink and shower drains, blocked gutters and around septic tanks.


Drain flies can breed very quickly, which is why infestations can get out of hand if not addressed.


What causes drain flies?


Drain flies are attracted to standing water and damp environments where they can breed. They feed on sludge and buildup from food, soap scum, grease, hair, mould, as well as fat, oil and grease (FOG). That’s why blocked drains and sewers are a breeding ground for drain flies. If your pipes don't drain properly or you have a blocked drain, it’s important to tackle the issue straight away to prevent a drain fly infestation.


Find out more information on the damage that FOG can cause in our article ‘Fatbergs: The data behind the growing phenomenon’.


How to get rid of drain flies


To get rid of drain flies, you need to remove their water supply so that they can’t breed and remove any sludge or blockages that they can feed on.


DIY methods to remove drain flies


If you want to try a DIY method, we don’t recommend putting chemicals such as bleach down the drains. Harsh chemicals can corrode and damage pipes over time, potentially leading to bigger and more expensive problems later on. Other methods, such as boiling hot water, are usually not strong enough to remove stubborn blockages.


The safest way to unblock your sink by yourself is to remove the blockage manually, either by using a plunger, drain claw or plumber's snake.


Our guide ‘How to unblock a sink by yourself’ includes a step-by-step tutorial of how to unblock your sink.


Regularly cleaning and reducing the moisture around your drains can help prevent further infestation.


Professional drain cleaning services


If you have an infestation that can’t be removed through DIY methods, you may need to call in a professional, such as Lanes. Your drains may require extensive cleaning, such as drain jetting or a CCTV drain survey, to find the cause of the blockage.


At Lanes, we specialise in inspecting, cleaning and clearing drains no matter the cause of your blockage. We can also repair your drains using our specialist drain relining equipment, should you need it. If you have a drain fly infestation that you can’t get rid of, have a look at our drain services online or call us on 0800 526 488 for a free quote.


How can I prevent drain flies from coming back?


You can prevent the return of drain flies by regularly cleaning your drains and eliminating their breeding grounds.


You can do this by:



  • Planning routine drain maintenance

  • Fixing drains that are draining too slowly

  • Clearing blockages as soon as possible

  • Removing any stagnant water

  • Ensuring drains are kept dry

  • Fixing leaks as soon as they occur


At Lanes, we’re on hand to help 24/7, 365 days a year. Contact us today to find out how we can help you with your drain blockage.

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