Fats, Oils & Greases

Fats, oil and grease (FOG) enters the sewer system when poured down the drains in restaurants, homes, apartments, industry and public facilities.

FOG is usually found in:

  • Butter, lard, shortening
  • Cooking oil
  • Meat scraps and grease
  • Baking goods
  • Sauces
  • Sour Cream
  • Gravy
  • Mayonnaise
  • Salad Dressings
  • Food Scraps

Report pollution or illegal dumping by calling the Pollution Hotline at 240-314-8348.

Still have questions? Contact:

Environmental Management

Wendy Blackman
111 Maryland Ave.
Rockville, MD 20850
Monday - Friday
8:30 a.m. - 5 p.m.

Cleaning a Grease Trap

Detach the Lid

Be sure to go slowly through this process, as there are gaskets for the grease trap located just under the cover. If you damage these, you will have to spend money to replace them.

Skim the Grease and Fat

Using a small bucket or ladle, skim the top layer of grease and fats from the interceptor. Gently guide it to the bottom of the trap, and swirl it lightly in the trap so that the grease and oils mark the dowel. This can provide you with a guide to how much debris is in the trap. If the amount of grease in the bottom of the trap exceeds 25 percent or one-fourth of the volume, the cleaning frequency should be increased.

Remove Water

Use a small bucket to remove any standing water from the tank of your grease trap.

Remove Waste

Using a small bucket, scoop into the trap and bring out the solidified waste. Place the waste in a water-tight container, such as a heavy-duty plastic trash bag.

Scrape Lid and Sides

Remove any large pieces of fat or oils that are attached to the trap. To achieve an even cleaner trap, you can use a wet/dry vacuum to suck out any smaller bits of waste.

Clean with Soap

Clean the lids, trap sides, and parts with soap and room-temperature water. DO NOT USE DEGREASERS IN THE GREASE TRAP. Use a steel pot scrubber to remove excess waste and odor. Flush the screens and parts with water to remove the soap and debris.

Reinstall and Record

Reinstall the grease trap making sure everything is secured. Record your cleaning dates in your grease abatement log so that you can stay on a regular schedule.