How Grease Buildup Damages Sewer Systems5

Many of us are aware that fats, oil, and grease (FOG) should not be poured down our sinks and drains. When these elements enter the sewer system, they can harden and cause problems for individual houses — and the city. Hardened FOG deposits restrict the natural flow of wastewater and cause sewage backups, resulting in costly damages. Over time, as more FOG accumulates, it can completely plug the pipes.

In freezing temperatures, encrusted FOG can be difficult to remove. Although mechanical removal helps eliminate stubborn encrustation, pipes can be damaged in the process.


The following are common sources of household fat, oil, and grease:


How Grease Buildup Damages Sewer Systems


  • Cooking oil, butter, margarine, lard
  • Meat and greasy food scraps
  • Gravy, sauces, salad dressings
  • Dairy products (e.g. yogurt, milk, cheese)
  • Lotions, soap suds, and body oil


Flushing these items does not mean getting rid of them. They simply build up in the pipes and come back to haunt you with various plumbing and health problems, including:


How Grease Buildup Damages Sewer Systems


  • Basement floods
  • Sewage overflow and backup
  • Disease-causing organisms
  • Slow draining
  • Costly repairs
  • Reduced pipe flow capacity
  • Contamination of water sources

How to Protect Your Sewer System


How Grease Buildup Damages Sewer Systems


The most effective way to prevent sewage overflow and backups is to keep your household pipes free of fat, oil, and grease. Here are some best practices to prevent the devastating and costly results of FOG buildup:


*Instead of dumping used cooking oil and grease down your sink or drain, store it in an old coffee can or sealable container and dispose of it properly in the trash bin.

*Use a paper towel to wipe greasy dishes and utensils before washing. Most FOG buildup comes from washing greasy kitchen items.

*Minimal use of garbage disposals can reduce kitchen sink blockage caused by greasy food scraps.

*Use strainers or drain baskets to catch food scraps and prevent them going down the sink. (Throw them in the organics bin.)



Beneath Toronto’s surface lies more than 11,000 kilometres of sewer pipes carrying wastewater. A large volume of hardened FOG buildup in the sewers is known as a “fatberg.” Because FOG is a serious problem, Toronto has taken crucial steps to keep its sewage system safe from fatbergs.

Practicing good grease disposal habits is the first step to maintaining the efficiency of your pipes and sewer. If the accumulation of FOG in your plumbing system has caused problems in your home or building, call Plumbing Authority Inc. at (647) 992-7473 or send us an email for a free onsite estimate. Our plumbers in Newmarket use state-of-the-art tools and CCTV camera to locate blockage. We are ready to serve 24/7, anytime, anywhere.