Reduce the risk of sewer back-ups: properly dispose of cooking fats, oils and greases

Reduce the risk of sewer back-ups: properly dispose of cooking fats, oils and greases

Utilities Kingston reminds residents to never flush cooking fats, oils and greases, or pour them down the drain. They clog pipes, creating sewer back-ups and problems with treatment equipment.

Cooking oil, butter and margarine, meat fats, salad dressings, sauces, and gravies are all types of fats, oils and greases (FOG). When poured down the drain or flushed down the toilet, they solidify and build up inside plumbing pipes, creating a sewer back-up risk in your home.

Don't let this happen to you!

This video shows a recent sewer blockage at a Kingston home.

The sewer is fully blocked at 10 metres and showed extreme grease encrustation. It resulted in sewage backing into the home, at considerable expense to the property owner. 

The problem

Grease is often poured down the sink as a warm liquid and solidifies as it cools, causing build-up inside pipes and restricting the flow of wastewater.  Consequences can include:

  • Raw sewage backing up into your home
  • An unpleasant and costly clean-up at the homeowner’s expense
  • Damage to the environment if wastewater overflows into parks, yards, streets, and local waterways
  • Health and safety risks (including, for example, hepatitis, bacterial infections, hypodermic needles, and slips and falls) for individuals cleaning up sewage and wastewater treatment operators

Each year, considerable resources are spent cleaning grease-clogged pipes and equipment throughout the municipal wastewater collection and treatment systems.

Proper FOG disposal

  • DO pour cooled grease, fat, or lard into a paper cup. Let the material solidify and then place it in your Green Bin. You can also soak it up with paper napkins or paper towel and place it in your Green Bin.  Tip!  Consider reusing those already soiled napkins from the dinner table to soak up excess FOG and place it in your Green Bin
  • DO scrape grease and food scraps from plates, pots, pans, utensils, grills, and cooking surfaces and place them in your Green Bin.
  • DO wipe out greasy pots, pans, and utensils with paper towel. Soiled paper towels and napkins can be disposed of in your Green Bin.
  • DO use a strainer in the sink to catch food scraps and other solids.
  • DO inform family members, friends, and neighbours about the problem with FOG in the sewer system and how to keep it out.
  • DO learn about proper waste disposal, using the City of Kingston’s terrific online tool

Other top clog offenders that don’t break down in treatment equipment include the following: wipes (FYI – so-called “flushable” wipes can cause clogs), paper towels, feminine hygiene products, dental floss, needles and hair. These should be disposed of in the garbage or Green Bin.

Learn how to properly dispose of these items and protect your home and health by knowing what not to flush. Visit