Back to top

Grease Management

Residential FOG

The build-up of fats, oils, and grease in the sewer system causes sewer blockages. This eventually results in sewer backups that can overflow onto streets and into homes, damaging property and the environment. Untreated sewage can flow into storm drain inlets, creeks, lakes or rivers. Most overflows are relatively small and can be stopped and cleaned up quickly. If not addressed, overflows can result in property damage, strong odors, and environmental, health and safety problems.

In neighborhoods that experience sewer blockages and backups due to fats, oils and grease sewer system maintenance is expensive and can contribute to increasing costs for sewer service.

Did you know that approximately 85 percent of grease-related sewer blockages and overflows originate in residential areas? All households play an important role in preventing neighborhood sewer system blockages. Cobb County’s goal is to take a proactive approach to pollution prevention which focuses on proper FOG disposal, thus protecting the environment and decreasing sewer maintenance costs.

Frequently Asked Questions

What is FOG?

  • FOG refers to fats, oil, and grease, which are the natural by-products of food preparation and cooking or baking. When poured down the drain, they can form clogs and blockages that lead to sewer overflows.
    • FAT
      Fats typically come from meat and dairy sources but can also come from plant sources, such as nut butter. It is usually in solid form at room temperature and can be thrown directly into the trash.  Placing these foods in the garbage disposal only reduces the size of the food, not the likelihood of creating a clog.  If you are not sure whether something contains fat, check the nutrition label.

      Unclogging Strategy: Place fats directly in the trash or another container before placing in the trash can for proper disposal.

      • ​​​​​MEAT TRIMMINGS 
      • CHEESES 
      • ICE CREAM 
      • BUTTER
    • OIL
      Oil comes from plant sources such as vegetable oil, canola oil, olive oil, corn oil, etc. It may be used as a topping on food, such as salads or sandwiches, or used to cook food, such as deep frying. It remains liquid at room temperature. Used oil should be poured into a can or jar before disposal.  If it is poured down the drain, oil can coat pipes and get into nooks and crannies, creating a slick surface that fats and grease stick to easily.

      Unclogging Strategy: Pour used oil into a jar or can with a lid before placing in the trash can. Hot water and soap do not eliminate oil; it will eventually reform in pipes. 

      • COOKING OIL 
      • CANOLA OIL
      • OLIVE OIL 
      • CORN OIL
    • GREASE
      Grease occurs when fats from food melt under heat such as frying, boiling, and baking, etc. Grease is deceptive because it is a liquid after cooking but eventually cools into a solid. Sometime after pouring it down the drain, it will cool on the pipes in the collection system, then harden, and start a clog.

      Unclogging Strategy: Pour liquid grease into a grease can or other containers with a lid and place in the trash once it has cooled. Running hot water over greasy cookware in the sink only pushes it into the pipes where it hardens.

      • FAT FROM MEAT 
      • GRAVY 

Contact Us

For information on Grease Devices and/or Plans Review for Restaurants and Food Preparation Establishments, please call:

Ernest Earn
Senior Project Manager
☎  770-419-6336
[email protected]

 - OR -

Linda Lowery
Plan Review Tech
☎  770-419-6327 
[email protected]  

CCWS Engineering Division
660 South Cobb Drive
Marietta, GA 30060

For inspection of grease traps or devices before installation, please contact: 

Jamie Stones
Grease Management Supervisor
☎  770-419-6430
[email protected]

CCWS Environmental Compliance Division
680 South Cobb Dr
Marietta, GA 30060-3113

Food Preparation Establishments

In Cobb County, our Grease Management Program monitors food establishments' compliance with Cobb County Water and Wastewater Ordinance regulations found in the Official Code of Cobb County Georgia Section 122-188. These regulations require all food preparation establishments, or any company that exceeds the wastewater limit for grease and oil, to have a grease recovery system. In addition, these ordinances require quarterly pumping of all exterior grease traps.

The Engineering Division of the Cobb County Water System approves grease devices for all new or renovated restaurants or change of owners/operators. Plans must be submitted for approval. There is a fee for each new seat. To find out if your business will need a grease device as well as what size will be required, contact CCWS Engineering at (770) 419-6336. For further information on plan review requirements and grease trap required detail specifications, please click on the Compliance tab above for more information.

In addition to submitting plans to CCWS Engineering, it is required that grease device inspections be done to ensure that the systems are functioning properly and are up to design specifications.  If a new exterior grease device is being installed, an inspection should be scheduled before backfilling occurs.  To set up an inspection please contact Environmental Compliance Grease Management Program at (770) 419-6430 or email [email protected] Please allow 24 to 48 hours for inspection scheduling.

Environmental Compliance registers all food establishments that have or are required to install a grease device. The application to register a grease device can be found in a PDF form under the Compliance down-menu on the right. Permitted food establishments are monitored through a system of manifest reporting, as well as routine inspection visits by Environmental Compliance Personnel.

Grease Management FAQs

What is FOG?

FOG refers to fats, oil, and grease, which are the natural by-products of food preparation and cooking or baking. When poured down the drain, they can form clogs and blockages that lead to sewer overflows. Did you know FOG can also clog the sewer pipes under the streets that take the wastewater from your house to the treatment plant? If that happens, the wastewater can back up and come to the surface and pollute the environment. This can allow untreated sewage to run into the streets and into our storm drains. This is not only a human health hazard but, since storm drains flow to creeks and rivers, this can cause significant environmental damage and impact aquatic life forms. You can avoid unnecessary expense and damage to the sewer system by following a few simple rules.

What is a collection system?

The collection system is a network of pipes and pump stations that moves wastewater from homes and businesses to one of the County’s water reclamation facilities (WRF).

Wastewater comes from everyday activities we all do, such as washing dishes, taking a shower, running the washing machine, and of course, flushing the toilet. Anything that goes down a drain enters the collection system.

How exactly does FOG clog up a pipe?

As a warm liquid, FOG goes down the drain easily. But once it cools, it sticks to sewer pipes and builds up over time.

Anything put down the drain, or garbage disposal, or flushed in the toilet (besides toilet paper) combined with FOG, can block the flow of wastewater through the pipe forcing it back up the drain resulting in flooding of a home, a street, or a stream with wastewater.

Does soap take care of FOG?

FOG does not mix with water. Detergents separate from the FOG after a period of time, and cling to the pipes, restricting the flow of wastewater.

If I don’t have an overflow, does FOG affect me?

Yes! If you are connected to the collection system, you have a vested interest in the reliability and lifespan of the system and treatment plants. Even if you never experience a FOG-related overflow, a portion of your monthly water bill payment funds the maintenance, repair, and replacement of the system.

In addition, the potential for ecological damage to the County’s waterways that contribute to the quality of life for all residents.

Is FOG a problem?

In the sewage collection and treatment business, the answer is YES!

FOG is singled out for special attention because of its poor solubility in water and its tendency to separate from the water and adhere to other surfaces. Fats, oils, and grease in the sanitary sewer coats the insides of the pipe, causing maintenance problems. The consequences include reduced sewer capacity and pipe blockages leading to sanitary sewer overflows. Oil and grease also hamper effective treatment at the wastewater treatment plant. Grease in a warm liquid may not appear harmful. But, as the liquid cools, the grease or fat congeals and causes mats to form on the surface of settling tanks, digesters, and the interior of pipes and other surfaces which may cause a shutdown of wastewater treatment processes. Problems caused by wastes from restaurants and other grease-producing establishments have served as the basis for the Grease Management Program and other regulations on the discharge of grease materials to the sanitary sewer system. Typically a grease trap or grease interceptor is required to control FOG discharges.

What should I do with leftover oil or grease?

Once it has cooled, place the used oil or grease into a container with a top. Dispose of the container in the garbage.

What foods are sources of FOG?

Food scraps, meat trimmings, poultry skin, the “skim” from soups and gravies, cooking oils, lard and shortening, salad dressings, sauces and marinades, dairy products including ice cream, butter and margarine.

What can I do to reduce FOG?

Following these basic practices in the kitchen:

DO NOT wash food scraps (solid or liquid) down the drain or grind them in the garbage disposal. DO scrape plates over the trash can. Use mesh drain strainers to catch remaining solid food scraps for disposal in a trash can.
DO NOT pour used oil down the drain. DO pour used oil into a container with a top and placed in the trash can for disposal.
DO NOT pour hot grease down the drain. DO place cooled grease into a garbage can for disposal.


Who can I contact for additional FOG information?

Cobb County's Grease Management Program coordinates FOG education and enforcement activities. They are located in the Office of Environmental Compliance and can be contacted at [email protected].