What is F.O.G?

Fats, Oils and Grease, which are found in:

  • meats,
  • salad dressing,
  • gravies,
  • sauces,
  • fryer oil,
  • butter
  • dairy products.

Why is it a problem?

When you pour these down sinks and drains, they cool and congeal inside the sewer pipes. They mix with other solids. This causes clogged sewer lines and backups into homes and businesses.

This endangers public health. Cleaning and repairing the sewer lines is costly. These costs are paid by water and sewer customers, as well as the homeowners and businesses that caused the backups.

Watch this short video: What Lurks Beneath Your Drain by the South Coast Water District.

You might also enjoy these other videos:

Science test

Products that say "flushable wipes" , try this test. Fill up two buckets of water and in one, place the "flushable wipe" in the other a piece of regular toilet paper.  Let it sit for awhile and then see how hard it is to rip them apart.  For something to be truly "flushable" it should rip apart easily when soaked in water. 


Grease is the worst offender. The warm liquid pours easily down the sink, but cools and creates major problems through the water and sewer system, which can lead to shutdowns at the treatment plant, or backups in your home or business.

Grease reduces pipe capacity, which means piping systems must be cleaned, and sometimes replaced, more often than planned.

Pouring F.O.G. down the sink costs us money.

Clogged Air Release Valve

F.O.G. In the Wastewater System

Air Release Valve (ARV)

Air release valves at the high points of the pipeline are designed to release air pockets out of the line. This helps pumps and piping move the liquids more effectively.

Grease coats the air release valve. At some point, it finally plugs the valve. When this happens, the result is:

  1. The valve cannot let air out of the line. The pumps have to work harder and longer.
  2. It lets sewage into a carbon canister which should always be dry.

Grease costs the water and sewer customers and the Plant money in worn pumps and higher maintenance costs.

Clogged Air Release Valve

Fouled Air Release Valve -Redwood Area

Vacuum Release Valve (VRV)

The yellow material is grease congealed on the red float on the release valve.

Grease clogged valves let sewage into the carbon canister. This 55 gallon canister filters the air releases to reduce odor. Odor increases when the canister is damaged.

Clogged Float on Valve

Red plastic float opens and closes the VRV assembly

Reducing F.O.G. at Home or Your Business

To Reduce F.O.G. at Home

  • Collect grease and cooking oil in a can. Store it in the refrigerator and put it in the garbage can on the day of pickup.
  • Scrape and wipe dishes, bowls, and pans into the garbage can before washing.
  • Install a food strainer in kitchen sink drains and empty them into the garbage can.


  • Pour greasy liquids down sinks or toilets.
  • Pour grease or oil down floor drains, parking lots or streets.
  • Use the garbage disposal.

FOG Program Flyer

Cover of Residential FOG Brochure

Reduce FOG at Your Business

  • Use a sealed grease dumpster or barrel to collect oils and grease for recycling.
  • Close the grease dumpster lid after use to keep the rain out.
  • Use a grease interceptor or oil/water separator.
  • Check and maintain interceptors regularly.
  • Clean interceptors and dispose of interceptor waste properly, not in the garbage can.

Kitchen Best Management Practices

Select image to watch YouTube video on Restaurant Oil and Grease Best Management Practices
Fog pic

Best Practices Flyer

Best Mngmt Practices for Restaurants Small