Blocked Drains: Causes and Other Info

Blocked drains are a common household issue that can lead to serious plumbing problems if not addressed promptly. Understanding the causes of blocked drains is essential for preventing these frustrating and often costly occurrences. In this article, we explore the most common culprits behind blocked drains, including grease, tree roots, broken pipes, and everyday items like hair and toiletries.

Grease

Grease contributes to drain blockages by solidifying and accumulating in pipes over time. When warm oil and fat from cooking utensils or oil-based products come into contact with cold water in the drainage system, they solidify and form a tough substance that can set as strong as mortar when mixed with silt and debris. This solidified fat can cling to the walls of the pipes, gradually building up and causing significant blockages. 

The accumulation of grease in pipes can lead to back-ups, slow drainage, and even water flowing out of drains during heavy rainfall or when using appliances like washing machines. To prevent grease-related blockages, it is crucial to avoid pouring grease and fat down the drain, limit the use of oil-based products in sinks and baths, and properly dispose of cooking oil and grease in the trash. Regularly flushing drains with boiling water and using eco-friendly degreasers can also help dissolve minor grease build-ups and maintain healthy plumbing systems.

Twigs and Leaves

Twigs and leaves contribute to drain blockages in several ways:

• Accumulation in Gutters and Drains. Leaves and twigs can accumulate in gutters and drains, especially during autumn. This can cause blockages within the property sewerage system unless regularly cleaned.
• Decomposition and Sticking. As leaves break down, they release substances that can stick to the inside of pipes, attracting more debris and worsening the blockage.
• Restricting Water Flow. Leaves and twigs can restrict water flow by clogging pipes and drains, potentially leading to overflows and water damage.
• Creating a Nourishing Environment for Tree Roots. Leaves and twigs can provide a nutrient-rich environment for tree roots to grow and infiltrate sewer lines, causing long-term blockages.

Tree Roots

Tree roots contribute to drain blockages in several ways:

• Infiltration. Tree roots can infiltrate sewer lines through small cracks or openings in pipes, seeking moisture and nutrients. Once inside, they can grow thickly along the interior surfaces, constricting drain flow over time.
• Expansion. As roots mature, they can expand and multiply, exacerbating blockages. This can lead to partial or complete blockages, where water cannot flow through the system.
• Pressure on Pipes. The growth of roots can exert immense pressure on pipes, causing them to crack or break, leading to severe blockages and costly repairs.
• Reduced Pipe Diameter. Tree roots can reduce the interior pipe diameter by wrapping around the walls, significantly impeding water flow.
• Blockage of Stormwater Drains. Tree roots can also enter stormwater drainage systems, causing blockages that lead to localised flooding during rain events.
• Recurring Issues. Once tree roots have infiltrated a pipe, they can continue to grow and cause recurring blockages unless properly managed. This can lead to repeated drain cleaning and repair costs.

Fat

Fat contributes to drain blockages in several ways:

• Fat solidifies in pipes. When warm oil and fat from cooking utensils or oil-based products come into contact with cold water in the drainage system, they solidify and form a tough substance that can set as strong as mortar when mixed with silt and debris.
• Solidified fat clings to pipe walls. This solidified fat can cling to the walls of the pipes, gradually building up and causing significant blockages.
• Fat accumulation leads to blockages. The accumulation of grease in pipes can lead to back-ups, slow drainage, and even water flowing out of drains during heavy rainfall or when using appliances like washing machines.
• Fat contributes to fatbergs. Fat can contribute to the formation of "fatbergs" - giant lumps of fat that can clog entire sewers and cost water companies thousands to break up.
• Fat sticks to drain edges. Quite often, the fat doesn't make it to the sewer; it sticks to the edges of the drains of your home instead and slowly builds up until it's blocking the path of everything else.

Broken Pipes

Broken or displaced pipes can create an edge or lip that catches solids and paper, leading to blockages. Regular inspections and maintenance can help identify and address these plumbing issues.

• Blockages from Pipe Collapse. When pipes break or collapse, water flow is impeded, leading to blockages as debris and solids get caught in the damaged section of the pipe.
• Edges Catching Solids. A broken pipe can have edges or lips that catch solids and paper flushed through the drains, creating a domino effect of waste building up and eventually blocking the drain.
• Difficulty in Diagnosis. It can be challenging to diagnose broken pipes, especially if the damage is not visible. This issue becomes more significant if there is limited space to inspect the problem area.
• Soil Sediment Entry. When a sewer pipe cracks or breaks, sediment from the surrounding soil can enter the sewer system, exacerbating blockages.

Toiletries

Toiletries contribute to drain blockages by being one of the common items that are mistakenly flushed down drains, leading to clogs. Items like baby wipes, cotton balls, sanitary products, diapers, and feminine products are often flushed down toilets, causing blockages in the sewer system. These toiletries can absorb water and double in size, quickly causing drain blockages. 

To prevent this issue, it is crucial to dispose of toiletries in a separate bin or garbage instead of flushing them down the drain. Proper disposal practices and educating household members about what can and cannot be flushed can help avoid drain obstructions caused by toiletries.

Poor Installation

Poor pipe installation can cause blocked drains in several ways:

• Incorrect Pipe Sizing. Poor installation can result in pipes that are too small for the water flow, leading to blockages. This can cause water to back up and accumulate, eventually causing clogs.
• Dips or Bellies in Pipes. Poor installation can also lead to dips or bellies in pipes, which can catch solids and debris, causing blockages. These dips can allow water to flow past but trap larger particles, leading to clogs.
• Incorrect Water Flow. Poor pipe installation can result in incorrect water flow, which can cause sediment buildup and reduce water pressure. This can lead to blockages and other issues.
• Fractured Pipes. Poor installation can also lead to fractured pipes, which can cause blockages as water flows through the damaged sections. This can be difficult to diagnose without professional equipment.
• Lack of Adequate Falls. Poor installation can result in pipes with inadequate falls, which can cause water to flow slowly and accumulate, leading to blockages.

Hair

Hair can cause blocked drains in several ways:

• Hair accumulates in pipes, especially in showers and sinks, and can create blockages over time. When mixed with soap, shampoo, and other cleansers, hair can solidify and cling to the walls of the pipe.
• Hair strands, especially long ones, can tangle and trap soap scum, creating dense blockages. The combination of hair and soap suds often results in clogged bathroom drains.
• In most cases, it's not hair alone that's causing the blockage. Soap and other cleansers, along with grease naturally occurring in the skin, can solidify part way down the drain and cling to the walls of the pipe. This gives hair something to cling to, and build up into a mass over time.
• Hair does not degrade in drains and can build into a full-blown blockage that floods your shower. It's crucial to invest in a quality hair strainer or hair trap that catches hair before it enters the drains to prevent future blockages.

Soap Scum

Soap scum contributes to drain blockages by forming a sticky, glue-like residue that accumulates in pipes over time. This residue, also known as soap scum, is created when soap mixes with minerals in hard water, such as calcium and magnesium. As soap scum builds up on pipe walls, it can attract other debris like hair, body oils, and dead skin cells, leading to gradual blockages in shower drains and other plumbing systems.

Soap scum can cause significant issues in several ways:

• Accumulation. Soap scum gradually builds up on pipe walls, creating a sticky residue that can catch other debris and hair, leading to clogs.
• Hair and Body Oils. Hair and body oils can mix with soap scum, forming a thick mass that can completely clog shower drains.
• Sticky Residue. Soap scum creates a sticky residue that can adhere to pipe walls, making it difficult to clear blockages without proper cleaning and maintenance.
• Mineral Build-up. Soap scum can also contribute to mineral build-up in pipes, which can further exacerbate blockages.

Freezing Pipes

Freezing pipes contribute to blocked drains in several ways:

• Expansion and Blockage. When water freezes, it expands, which can cause significant blockages in pipes. This expansion can lead to partial or complete blockages, especially if the pipes are not well-insulated.
• Pipe Damage. Frozen pipes can burst or crack, causing significant damage to the plumbing system. This damage can lead to further blockages and costly repairs.
• Water Back-up. If water cannot flow through frozen pipes, it can back up into the drain, causing sewage to flow back into the home. This can lead to unpleasant odours and health hazards.
• Increased Debris Build-up. Frozen pipes can cause debris like hair and soap scum to accumulate and stick to the pipe walls, making it more difficult to clear blockages.
• Increased Risk of Tree Roots. Frozen soil can cause tree roots to infiltrate sewer lines more easily, leading to additional blockages.

Minerals

Minerals, particularly calcium and magnesium found in hard water, can contribute to blocked drains in several ways:

• Mineral buildup. Over time, minerals dissolved in hard water can deposit on shower and pipe walls, accumulating and narrowing the pipe diameter, which impedes water flow.
• Soap scum formation. Minerals in hard water can react with soap to create a sticky, glue-like soap scum residue that builds up on pipe walls. This residue can attract other debris like hair and body oils, leading to gradual blockages.
• Exacerbating other blockages. Mineral deposits can worsen blockages caused by other factors like grease, fat, and hair by providing a surface for these substances to adhere to and accumulate.
• Damage to pipes. Over time, mineral buildup can cause damage to pipes, leading to cracks, corrosion, and structural issues that contribute to blockages.

Seek Professional Help ASAP to Help with Blocked Drains

If you’re having a hard time dealing with the causes that lead to clogged drains, don’t hesitate to contact us. We will help you assess the cause of the problem and present you with plumbing solutions so you can deal with it better. We will also provide you with suggestions on how you can easily maintain the integrity of your drains over time.