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Restaurants and businesses play a major role in reducing FOG in Gwinnett County’s collection system. Whether it’s your favorite fast food stop, a neighborhood pub, or that special occasion restaurant, all of them must meet the requirements of the County’s FOG ordinance.

Some businesses and government institutions are subject to it as well, such as daycares, assisted living facilities, schools, hotels, hospitals, even the jail – essentially any place that processes food, operates a commercial kitchen or sells food.

FSEs must install appropriate size grease traps before they can connect to the collection system and are responsible for ensuring the trap is kept in good working order. This means following the 30% Rule that calls for pumping out an outdoor trap at least every 90 days and an indoor trap at least every 30 days.  FSEs must also keep maintenance records and use only licensed grease haulers to pump out the traps. The ordinance also encourages following FOG best management practices (BMPs) around the kitchen.

DWR employs three full-time inspectors who regularly visit FSEs to confirm that they are following the ordinance standards. In 2008, they completed 3,015 compliance inspections – an average of more than 11 a day! During these visits, they follow an inspection checklist that looks at the condition of the trap and also whether good maintenance records are being kept.

Examples of Food Service Establishments (FSEs)

  • Restaurants   
  • Coffee shops
  • Cafeterias
  • Short order cafes
  • Luncheonettes
  • Taverns
  • Lunch rooms
  • Places manufacturing, wholesaling, or retailing sandwiches,
    salads or other fast foods
  • Soda fountains
  • Institutions ( public and private)
  • Food carts
  • Itinerant restaurants
  • Industrial cafeterias
  • Catering establishments
  • Food vending machines, including vehicles and operations
    connected to business

Source: Gwinnett County FOG Ordinance

FOG Ordinance Terms to Know

DWRSSS:  the current Gwinnett County Department of Water Resources sanitary sewer standards

Grease Trap: a device in which the grease content of wastewater is intercepted and congealed, and from which grease is removed for proper disposal. The term "grease interceptor" may also be used.

Food Service Establishment (FSE): includes establishments for the preparation or serving of meals, lunches, short orders, sandwiches, frozen desserts, or other edible products. See examples list for businesses considered FSEs.

30% Rule: rule governing grease trap maintenance. It requires that the depth of both bottom solids and oil/grease in a trap shall not equal or be greater than 30% of the total operating depth of the trap. The operating depth of a trap is the internal depth from the inlet or outlet water elevation to the bottom of the trap.

Kitchen Best Management Practices (BMPs)
Gwinnett’s FOG ordinance encourages FSEs to take a proactive approach to FOG reduction in the kitchen.

These best management practices (BMPs) help minimize the likelihood of damage to the collection system and also help protect the environment from spills and overflows.
They help prevent damage to the business as well. Blockages and backups in the kitchen can result in costly plumbing repairs that can eat into the business’s bottom line.  Following good BMPs may also extend the maintenance intervals needed for the grease trap. 

FOG BMPs for Commercial Kitchens

Avoid wet clean up – remember the hose is not a broom.

  • Use dry clean up FIRST for equipment, utensils and serving pieces. This can be done with scrapers, squeegees, and absorbents that keep the bulk of food pieces and oil and grease from going down the drain.
  • Install drain screens to catch food particles instead of washing them down the drain.
  • Ban the use of garbage disposals. The drains they are in typically connect directly to the collection system and do not go through the grease trap.
  • Wipe down work areas with paper towels before cleaning.  

  • Pour liquid FOG into a container before washing dishes and throw the container away when it is full. Be sure to keep a lid on it to avoid spills.
  • Collect waste grease from fryers in recycling bins.
  • Empty grill scrap baskets or boxes into a container.
  • Install approved low flow faucet fixtures.
  • Post procedures over sinks to remind employees of FOG reduction techniques.
  • Establish spill prevention and clean up procedures.
  • Develop and post spill procedures
  • Train employees to implement procedures
  • Designate key employees to monitor clean-ups

How a Grease Trap Works

A grease trap or interceptor works by "trapping" grease and food at the FSE site so it does not enter the sewer collection system and contribute to spills and overflows. In Gwinnett, the trap must have a capacity of at least 1500 gallons. Click here to download the County’s grease trap specs.

Example of Grease Trap

Sink and floor drains in a commercial kitchen connect to an inlet pipe, which sends the water into a double-compartmented basin. The first section is called the primary separation basin. Anything that is washed down the drains gets held here. This helps cool any grease so it solidifies. Because the grease is lighter than the water, it floats on top. Food particles are heavier than the water and sink to the bottom.
A baffle between the two compartments with an opening at the bottom of the basin or a pipe through the baffle wall lets the cleaner water flow into the secondary separation compartment.

If any grease manages to pass through the primary basin, it is caught in the secondary basin.
An outlet pipe that is above the "normal liquid" level discharges the water into the County collection system.

A "normal liquid" level must be maintained in the grease trap to help keep the grease in the primary separation area while at the same time allowing the water to flow through the trap.

There is typically a monitoring site at the outlet pipe, so inspectors can make sure the trap is working properly and whether extra maintenance is needed.
Licensed grease haulers then pump out the contents of the grease trap on a regular basis.
Some of this grease can be recycled and is used in many everyday products such as pet foods, cosmetics, soap, and skin care products

Adding enzymes or bacteria to the grease trap as a maintenance step does not really work because it only breaks up FOG temporarily and moves it downstream. It can reform into clogs in the collection system. Additionally, Gwinnett’s FOG ordinance prohibits additives to grease traps.

Download our brochures to learn how you can help "Unclog the  FOG"