Frequently Asked Questions

What is FOG?

FOG stands for “Fats, Oils and Grease” and is found in your kitchen. The main source of FOG in sewer pipes is used grease from cooking and food preparation which is poured down the kitchen drain. Many of the foods we eat everyday contain FOG including meats, sauces, salad dressings, fried dishes, cookies, pastries, butter and many others. Food scraps washed down the drain also contribute to FOG in sewers.

Why is FOG a problem?

FOG does not mix with water and separate from liquid in the sewer system. FOG, especially grease dissolved in hot soapy water may not appear harmful but when released into the sewer system the soapy liquid cools significantly, causing the grease/fats to separate from the water and adhere to the surface of sewer pipes.

Once inside sewer pipes grease builds up decreasing pipe capacity and causing clogs. The restricted flow of wastewater through the pipes often results in sanitary sewer overflows which can damage property and pollute the environment. Blocked pipes require additional cleaning, maintenance, and replacement. These additional costs are passed on to citizens in the form of higher wastewater bills.

How big is DeKalb County’s FOG problem?

DeKalb County has a huge FOG problem.  Since 2006, the county has had upwards of 1000 sanitary sewer overflows. As a result, DeKalb County is under a federal consent decree to eliminate its combined sewer overflow in 8.5 years.  Seventy (70) percent of these overflows were due to clogs in sewer pipes caused by FOG.

What types of problems are caused by FOG related sanitary sewer overflows?

·         Back up of raw septic sewage into homes

·         Expensive and unpleasant clean up that citizens’ pay for

·         Raw sewage overflows into neighborhoods, parks, yards, and streets

·         Potential contact with disease-causing raw sewage

·         Higher sewer bills due to increased operation and maintenance costs

What can you do to help?

The first line of defense and the easiest way to solve the FOG buildup problem in your community and help prevent sewage overflows is by keeping fats, oils, and grease out of the sewer system. Here are a few tips:

  • Never pour grease down sink drains or into toilets.
  • Scrape grease and food scraps from trays, plates, pots, pans, utensils, grills, and cooking surfaces into a can or the trash for disposal.
  • Wipe off small amounts of grease and oily residue from sauces, salad dressings, etc., with a paper towel before rinsing the kitchenware in the sink.
  • Pour fats, oils, and grease into a container such as an empty jar or coffee can. Store the container in the refrigerator or freezer until full, secure the lid and dispose in the household garbage.  
  • Don’t put grease down garbage disposals. Use baskets/strainers in sink drains to catch food scraps and other solids, and empty the drain baskets/strainers into the trash for disposal.
  • Communicate with your friends and neighbors about the problem of grease in your sewer system and how to keep it out. The solution starts right in your home with your actions.
Are garbage disposals and detergents effective on FOG?

No. Home garbage disposals do not keep grease out of the sewer system, nor will it prevent grease from building up. Products such as detergent and dishwashing liquid that claim to dissolve grease simply pass the grease down the pipeline causing problems elsewhere downstream.

Why are oils that do not harden a problem?
Oils entering the system cause problems in three ways:
  1. Many oils actually do harden at lower temperatures and therefore clog the system. Even if they don’t solidify they often bind to other forms of fats and grease.
  2. Some oils move through the system so quickly that they cannot be fully broken down in the treatment process.
  3. Oil droplets can concentrate other contaminants, leading to food chain problems for aquatic animals.
How should I dispose of fats, oils and grease?

Small quantities of fats, oils, and grease should be left to cool and then stored in the refrigerator or freezer. Once the container is full, it can be discarded in the household garbage. Smaller amounts of cooled grease, salad dressings and sauces can be absorbed with a paper towel and tossed into the garbage.

What should I use to store FOG before disposing of it?

One of the goals of residential source control is to reduce waste at its source in the most effective and convenient way. Use a container that is readily available, heat resistant, and sturdy. Used paper coffee cups may be an option. Experiment with various containers to find the best option for you. The key is to wait until the container is full before disposing.

DeKalb County should explore FOG disposal options that impose minimal or no cost to residents and are easily accessible and safe.
Isn’t throwing containers full of grease into the landfill just creating a different problem?

Sending FOG waste to the trash may be viewed as simply transferring the problem.  However, absent any other practical alternatives, sending FOG to the trash is the best option until DeKalb County develops other alternatives. Fats, oils and grease cause greater environmental problems when they enter the wastewater system.

What should I do with large quantities of cooking oil?

Large quantities of cooking oil, such as used deep fryer oil, should be cooled and poured into its original container. Freeze, if possible, and dispose of in the trash or recycle, if available.

What about restaurants and the large amounts of fat and oil they use?

In 2007, DeKalb County passed a FOG ordinance and since that time has worked with restaurants to reduce FOG through education, regulation, and regular monitoring. Properly sized grease traps are mandatory in all commercial eating establishments. Non-compliant food service businesses are subject to fines.

Why should homeowners take the responsibility for reducing FOG and making the environment cleaner?

Prevention is the best and most economic alternative. Preventing FOG from entering the sewer system is more cost effective than fixing the problem through operations, maintenance, and pipe cleaning. Additionally, some contaminants cannot be removed through treatment, or only through very expensive treatment options.

 Additionally, for the past five years the county’s FOG source control program has focused primarily on the restaurant industry. Given the current magnitude of the problem, the county has no choice but to expand its FOG source control program to include multi-family/apartment complexes and single-family households through an aggressive and targeted community education program.
What impact does FOG have on the environment?

·         In the absence of treatment, FOG can deplete oxygen in receiving waters.

·         Oil droplets can concentrate other contaminants leading to food chain problems for aquatic animals.

·         Sanitary sewer overflows introduce a variety of high priority pollutants to our creeks and river.

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PO Box 1341 | Decatur, Georgia 30031
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