Can Blocked Drains Cause Foul Odours?

Upside Down tech with van (blocked drains)

There’s a smell wafting into your nostrils and it’s downright foul. You’re immediately on guard and before long, your suspicions are confirmed − that repugnant odour originates from your blocked drains.

While often taken for granted, your drainage system works around the clock to whisk away water and waste from your home.

When this crucial system confronts a hurdle like a blocked drain, the consequences can range from minor inconveniences to major issues, including, you guessed it, nasty smells!

Common Culprits of Blocked Drains

Every household faces different classes of culprits when it comes to blocked drains. From the kitchen to the bathroom, different objects and substances can cause blockages.

Let’s discuss some common offenders that are causing your drains to block and stink up your home.

  • Food waste and grease build-up − Your kitchen sink, having seen the last of the supper scraps, coffee grounds, and cooking oil, is a prime candidate for blockages. Food debris left on plates and cutlery often finds its way down your drain, leading to a build-up. This, combined with a dense layer of grease solidifying in your pipes, can create stubborn blockages in no time.
  • Soap residue and hair − Soap scum and hair are the silent sentinels of blocked drains in your bathroom. Be it from shaving, washing your hair or lathering up, these substances combine to form a sticky mass that blocks your drains and impedes water flow.
  • Tree roots in outdoor drains − Tree roots can invade your outdoor drains, attracted by the abundant supply of nutrients and moisture. If not promptly addressed, tree roots can grow extensively, causing severe blockages and heavy damage to your drain pipes.

Signs to Watch Out For

Recognising the early warning signs is the first step towards taking swift action against blocked drains. Here are some key signs to look out for, which indicate that your drain might be blocked.

  • Slow draining − Notice a pool of water taking its sweet time to drain after a shower? This increasing lag is often the earliest indicator of a blocked drain.
  • Gurgling sounds − Gurgling sounds from your drains, similar to coffee percolating, are audible signs of blocked drains. When water meets resistance due to a clogged drain, it tries to navigate around it, creating these sounds.
  • Foul smells − An unpleasant aroma arising from the drain hole can be attributed to food waste rotting in your blocked drain. This decaying matter releases a pungent odour, which is compounded by stagnant water in your drain system.
  • Regular backups − If your drains constantly back up, overflowing from sinks, toilets or bathtubs, this recurring problem might indicate a blockage within your piping system. Regular backups are a sign that you might have a deeper, widespread issue at hand.
  • Overflowing toilets − A toilet that constantly overflows after flushing is definitely a sign of a blocked drain. Such occurrences are often a direct result of obstructed sewer pipes.
  • Fruit flies − An unusual increase in the number of fruit flies around your kitchen sink might be a subtle sign of a blocked drain. Fruit flies are attracted to decaying organic matter, which can get stuck in your pipes and create a perfect breeding ground for these pests.
  • Water pooling around drains − If you notice water pooling around your drains, especially after a shower or washing dishes, it is a strong indicator of a blocked drain. This is a sign that the blockage might be serious and needs immediate attention.
  • Unusual noises from your pipes − Besides the usual gurgling, if you notice other unusual noises like bubbling or knocking coming from your pipes, it’s a potential sign of a blocked drain. These noises are caused by trapped air within blocked pipes.
  • Changes in water levels in your toilet − Changes in the water level in your toilet bowl could indicate a main sewer blockage. If the water level in your toilet bowl is abnormally high or low, you could potentially have a serious blockage in your drain pipes.
  • Slow filling of your washing machine − If you notice your washing machine is taking longer than usual to fill up, this could be a sign of a blocked drain. Slow water flow might mean water is struggling to get through due to a blockage in your pipes.

Harmful Effects of Blocked Drains

Aside from their remarkable smell, blocked drains also pose several significant risks. From health concerns to environmental impact, let’s walk through the harmful effects of blocked drains to understand the importance of addressing this issue promptly.

  1. Health risks: Blocked drains can become breeding grounds for bacteria and mould, which thrive in stagnant water and can cause health issues such as allergies and respiratory problems if not promptly addressed.
  2. Property damage: If left unattended, blocked drains can cause pipes to burst or leak, leading to water damage to your property. Water leakage can cause structural damage and foster the growth of mould and mildew.
  3. Contaminated water: Blocked drains, especially those connected to your sewage system, can cause wastewater to back up into your home. This can lead to contamination of clean water sources, posing a significant health risk.
  4. Increased costs: The longer a blocked drain is left unchecked, the more severe the blockage gets. This can translate into costlier repairs and replacements down the line. Unblocking drains in their early stages can help to avoid such high costs later.
  5. Environmental impact: Blocked drains can lead to sewer overflows, which negatively impact local waterways and harm the overall environment. Such overflows introduce pollutants and hazardous materials into the environment, thus affecting local flora and fauna.

Can You Unblock Drains by Yourself?

While hiring a professional is always a wise choice for complicated issues, there are some smaller blockages that you can handle yourself. From easy home remedies to understanding when to call in the professionals, let’s delve into ways to unblock your drains.

Quick Home Remedies

A critical skill for any homeowner is the art of clearing blocked drains using a simple drain cleaner solution. Pouring boiling water down the drain is a straightforward solution because the hot water can often dissolve the offending blockage.

For kitchen sinks, a concoction of equal parts baking soda and white vinegar poured down the drain can break down fat and food build-up, keeping your drain running smooth. A wire hanger or a DIY drain snake can be handy tools to dislodge foreign objects causing your blockage.

DIY Risks

However, a word of caution: DIY remedies carry their own risks. Overuse of caustic cleaners could deteriorate your PVC pipes, and a drain snake or a drain auger, if misused, can result in a broken pipe.

Time to Call a Professional Plumber

For all the DIY enthusiasts out there, there comes a time when professional help on how to clear a blocked drain.

Assessing the severity of the blockage, dealing with pipe repairs, and establishing maintenance schedules will be better handled by a professional plumber for effective and lasting solutions.

  • Extensive blockages − Clearing blocked drains might be beyond you when dealing with severe blockages. A professional plumber with the right tools (like a plumber’s snake) and expertise can effectively clear blocked drains.
  • Drain and pipe repairs − If your ongoing issues are due to a broken pipe, a solution might involve pipe relining. This process creates a new, durable pipe within the old pipe, effectively resolving your blockage issues without extensive excavation.
  • Regular maintenance − To prevent blocked drains, create a maintenance schedule with your local plumber. Regular check-ups help detect potential issues before they manifest into expensive problems. Furthermore, using bacteria-based enzyme cleaners on a monthly basis can help maintain free-flowing drains.

Preventing Blocked Drains

Prevention is undeniably better than cure, especially when it comes to blocked drains. Several preventive measures can be undertaken right at home to eliminate the risk of clogs. Let’s explore these household strategies for maintaining clear and efficient drains.

  1. Install drain strainers: Installing a used drain strainer on sink and shower drains is an effective prevention method. These strainers catch hair, food debris, and other materials, preventing them from entering and potentially clogging your drain pipes. Regularly clean and empty these strainers to maintain water flow.
  2. Dispose of grease correctly: Instead of pouring cooking fats and oils down the kitchen sink drain, collect them in an old jar or container. Once full, toss the container in the bin. This practice prevents grease build-up in pipes that could cause blocked drains.
  3. Be mindful of food waste: Scrape leftover food from plates into the bin, not the sink. Avoid putting starchy foods like pasta or rice, fibrous materials like fruit peels, and coffee grounds down the drain, as they can exacerbate the likelihood of clogged drains.
  4. Maintain outdoor drains: Keep outdoor drains clear of leaves, debris, and other natural obstructions, especially during heavy rain periods. Regularly inspect your outdoor drains and consider installing drain grates to keep larger debris from entering the system.
  5. Properly dispose of sanitary products: Items like wet wipes, sanitary products, and dental floss should be disposed of in the bin to prevent them from causing blocked drains or blocked toilets.
  6. Monthly drain cleaning: As a part of your cleaning routine, pour boiling water down your drains each month to dissolve any buildup of soap scum, hair, and grime. For an added touch, consider using natural cleaning solutions like baking soda and vinegar mixture.
  7. Conduct regular plumbing inspections: Schedule periodic inspections by a professional plumber to identify any potential issues in your drainage system. These check-ups help detect early signs of drain blockages and prevent costly repairs.

Clear Blocked Drains Now

To cut to the chase, blocked drains do cause foul odours as rotting food waste and stagnant water combine into a less-than-pleasant cocktail. Recognising early signs of a blocked drain is pivotal to preventing blocked drains and their associated issues.

From DIY remedies like hot water and baking soda to hiring a professional plumber, unblocking drains is a non-negotiable way to maintain a healthy home environment.

So, next time you’re washing dishes, ensure food scraps don’t enter your drain, or better yet, during the heavy rain, make sure outdoor drains are not obstructed. The key here is regular maintenance and quick action when confronted with a potential blockage.

Now, clear blocked drains and sigh a breath of relief as you wave goodbye to foul odours and hello to freely flowing drains.

Please note: This information is provided for advice purposes only. Regulations differ from state to state, so please consult your local authorities or an industry professional before proceeding with any work. See our Terms & Conditions here.


Last Edited on: 14th February 2024