Grease Blockages in Sydney Drains During Winter

Is Grease Causing Your Drain Blockage?

In July 2025, Sydney Water reported over $12 million in damage to wastewater systems due to grease, fat, and dairy-related blockages. Many of these blockages started in household kitchens across the city. In winter, especially in Sydney's inner suburbs, fats and dairy waste cool and harden quickly inside pipes. The result is slow drains, bad smells, or complete backups that often require professional intervention. In many of these cases, high-pressure water jetting or trenchless pipe relining is needed to clear or repair the affected lines.

Cooking oils, meat grease, milk, and dairy-based sauces often get rinsed down sinks. While they may appear harmless when hot, they solidify as they cool and stick to the inside of drainpipes. This causes layers of build-up that trap other debris. The problem is common in areas with older plumbing systems, shared pipes, and narrow bends.

Residents in Surry Hills, Leichhardt, Redfern, Newtown, and similar suburbs see more of these issues during colder months. Kitchen sinks in these areas tend to clog more frequently due to congealed fat. Early signs include water draining slowly, gurgling sounds, or foul odours. Ignoring these symptoms can lead to full blockages and damage to your plumbing system.

How Do You Clear Grease at Home Without Tools?

You can manage minor grease build-up using basic kitchen supplies. These methods work best for early-stage clogs or as a regular maintenance routine. They do not remove deep or hardened blockages.

Boiling water and dish soap is a simple method. Pour a few drops of dish soap into the drain and follow it with a full kettle of boiling water. This combination can soften and flush away some of the grease lining the pipe. Let it sit for a few minutes before running more hot water.

Another method involves baking soda and white vinegar. Pour half a cup of baking soda down the drain, then add half a cup of vinegar. Let the mixture react and sit for twenty minutes. Finish with boiling water. This method may help with smell and light build-up but will not fix larger blockages.

You can also try a manual drain snake. This flexible tool can reach into the drain to break up grease clumps. Use caution, especially with older pipes. If the blockage lies deeper in the line, the tool may not reach it.

When Do You Need a Plumber for Fat Clogs?

If your drain stays slow or backs up despite home efforts, contact a plumber. Fat and grease can move further into the plumbing system where boiling water and home tools cannot reach. This often happens in multi-storey buildings or terraces where several households share a common drain.

A blocked drain plumber in Sydney can inspect the system and use equipment that reaches deeper into the pipes. High-pressure water jetting, also called jet blasting, is a method that breaks apart built-up grease and flushes it away. This process clears the pipe without damaging it. Plumbers also use drain cameras to check for cracks or deeper issues.

In some cases, grease damage leads to repeated blockages or cracked pipes. If this happens, the plumber may recommend trenchless pipe relining. This method repairs the pipe from the inside without digging.

Book a jet blaster service for deep pipe cleaning.

Why Shared Systems in Inner Sydney Are More Affected

Older buildings in Sydney often have shared vertical drainage systems. One resident’s disposal habits can affect several units. In high-density suburbs like Alexandria or Marrickville, fat and oil blockages in one flat may lead to overflows in another. These shared systems collect waste from multiple kitchens, and fat clogs can cause widespread plumbing issues.

These buildings also tend to have older pipes that collect residue faster. Cold weather causes fats to harden within minutes. Grease dumped from a top-floor kitchen may congeal halfway down the stack, blocking flow for units below.

Signs of a serious grease clog in a shared system include water rising in multiple sinks, bad smells coming from bathroom drains, or backups that return after being cleared. If this happens, building management should call a plumber for an inspection.

What Not to Pour Down the Drain

Prevention begins with better habits. Many residents do not realise that common kitchen waste causes long-term problems. Grease and dairy solidify in cold pipes and combine with food particles to form clogs.

Items to keep out of your drain:

• Cooking oil and animal fat
• Butter, margarine, and cream
• Milk, cheese sauce, and dairy soups
• Meat scraps or gravy
• Coffee grounds and food particles

Let grease cool, then scrape it into a container and throw it in the bin. Wipe greasy pans with a paper towel before washing. Pour milk and other dairy liquids into a sealed container and place it in the rubbish. Do not rely on hot water alone to break down fat, as it cools quickly in winter.

How to Prevent Drain Blockages

Simple changes at home can reduce the risk of clogs. Install a sink strainer to catch solids. Scrape plates before rinsing. Pour boiling water down your kitchen sink once a week, especially during colder months.

Schedule drain cleaning if you live in a high-risk area or notice recurring issues. Residents in the eastern suburbs, inner west, and North Sydney report more blocked drains in winter due to shared systems and older plumbing.

Blocked toilets are also linked to kitchen grease issues. When the main sewer line clogs, it can cause toilets to overflow. This leads to more damage and requires blocked toilet repair in addition to drain clearing.

Why DIY Methods May Not Be Enough

While home methods may offer short-term relief, they often do not solve the entire problem. If you’ve used boiling water and soap multiple times with no improvement, the clog is likely further down the pipe.

Chemical cleaners are not recommended. They can damage older pipes and do not remove grease build-up. Manual snakes also have limited reach. In most cases, a professional plumber using jet blasting equipment can clear the entire line safely.

Regular maintenance and early action help avoid expensive repairs. A plumber can identify risks early and recommend the best solution for long-term pipe health.

Book Your Drain Cleaning Today

Grease, oil, and dairy waste cause serious drain problems across Sydney each winter. If your kitchen sink is slow, smells bad, or continues to back up after cleaning, it is time to take action.

Proximity Plumbing provides drain inspections, jet blasting, blocked toilet repair, and trenchless pipe relining across the eastern suburbs, inner west, and surrounding areas. We service homes, apartments, and commercial buildings. If your property has old plumbing or shared pipe systems, regular cleaning will save you from costly damage later.

Call us to book a professional drain cleaning and remove grease build-up before it causes bigger issues at 0420-102-394.