Blocked drains can be very messy, and very expensive when not maintained.

A blocked sink or clogged toilet is highly unpleasant and inconvenient, but it can also cause a serious health hazard and shut facilities down.

Below are some common causes of blocked drains in commercial kitchen and bathrooms, and how to fix and prevent them in the future.

What Are the Signs of a Blocked Drain?

Some early warning signs that you might have a blocked drain include:

  • Foul-odour – when a clog is present it’s accumulated over time, causing a stoppage. You may smell a sulphur-like pungent odour from decomposing solids, bacteria build up and stagnant water.
  • Gurgling sounds- if the drain blocked a main sewer drain you will generally hear gurgling in your basin or tubs when you drain another at the same time.
  • Change in flush – A drain clog can make the toilet water levels rise higher or drain it of water.
  • Drips, puddles and wet floors- these often occur because of an overflow or pressure built in one spot, although in some cases it could be a leak.
  • Slow-draining basins/toilet bowls
  • Changes to water pressure

Knowing these symptoms will help you identify issues before a serious problem develops.

What Problems Does a Blocked Drain Cause?

Blocked outdoor, kitchen and bathroom drains are not only disruptive, they can lead to continual and costly problems. Some of these include:

  • Foul odours
  • Stagnant water, which attracts insects, pests and cause foul odours
  • Water stains on your walls and ceilings
  • Increased water bills caused by leaks
  • Sewage discharge on your property
  • Broken or burst pipes
  • Flooding
  • Overflow of water from mains if pipes are connected

How Can I Prevent A Blocked Drain?

Many drainage problems can be avoided with regular preventative maintenance. Here we take a look at three of the top causes of blocked drains and the best ways to prevent them.



Solution and Prevention


Toilet Paper or baby wipes An overuse of toilet paper or a thicker material like wipes in a toilet bowl can bunch up and clog the system Limit the use of toilet paper especially in the children’s toilets by adding a string to the toilet dispenser to show kids how much they use. As for baby wipes, these should always be put in a rubbish bin as the thicker material clogs the drains
Toys and objects We all know kids are curious by nature and love to put their toys in everything! The problem is drains, sinks or toilet bowls can’t necessarily handle it, add toilet paper on top and you have a recipe for an expensive clog If you can stop them from bringing them into the bathroom then that would be the first solution however if it’s past that point try using the plunger or using a hook.


We know it’s tempting and oil might be a liquid, but it shouldn’t be poured down a sink.

The build-up of grease from cooking oils is a common cause of clogged pipes, slow drains and water backup. The grease and lard in oil solidify as they cool, building up inside the drain and attracting more grime, often causing foul smells.

Avoid pouring oil down the drain. Place oil into a container and throw it away in the bin.

Pour 2–3 litres of boiling water at least once a week to prevent build-up. If you have a grease trap, make sure you clean it every 4–6 weeks.

Food scraps


Many people throw food scraps down the drain without considering the impact it can have on their pipes. Food scraps get stuck and block your drain, but they also grow bacteria and mould, producing a sewage-like smell. Use a sink strainer to catch large residue and debris that could contribute to a blockage.

Scrape food off plates into a bin or compost before rinsing in the sink.

Never tip coffee ground down the sink. Coffee granules don’t break down in water and will clump together to clog your pipes.

How to Fix a Blocked Drain

For a Kitchen or bathroom sink: To start, pour several litres of boiling water down the sink. Use a plunger and then pour through more boiling water.

To correctly use a plunger, place the cup over the entire drain opening and cover the lipped rim with water. Push the plunger up and down to create suction and push the clog down the drain. If the drain is still blocked, use a chemical drain cleaner or, for a more environmentally friendly option, a mixture of baking soda and vinegar.

For a toilet: Use plunger as above, if it continues reduce water use and get in touch with a plumber as soon as possible to reduce further problems

If it’s still blocked phone a professional as there may be more to it then you think.

Need help unblocking a drain?

Mathiou Services have qualified plumbers on call 24/7 phone us on 1300 363 423