Fats, Oils, Grease (FOG) Program

In recent years, the City of Joliet has undertaken efforts to improve the public sewer system and reduce the amount of sewer backups and sanitary sewer overflows (SSOs) that occur in the system. To reduce the amount of Fats, Oils, and Grease (FOG) entering the system, the City included requirements for Food Service Establishments (FSEs) in its 2019 ordinance.

Fats, Oils, and Greases aren’t just bad for your arteries; they’re bad for sewers too. Sewer overflows and backups can cause health hazards, damage home interiors, and threaten the environment. An increasingly common cause of overflows is sewer pipes blocked by grease. Grease gets into the sewer from household drains as well as from poorly maintained grease traps in restaurants and other businesses.

Residential Information

Too often grease is washed into the plumbing system, usually through the kitchen sink. Grease sticks to the insides of sewer pipes (both on your property and in the streets). Over time the grease can build up and block the entire pipe. Home garbage disposals do not keep grease out of the plumbing system. These units only shred solid material into smaller pieces and do not prevent grease from going down the drain. Commercial additives, including detergents, that claim to dissolve grease may pass grease down the line and cause problems in other areas. The results can be a sanitary sewer back up in your home.

The easiest way to solve the grease problem and help prevent overflows of raw sewage is to keep this material out of the sewer system in the first place. There are several ways to do this. 

• Never pour grease down sink drains or into toilets. 
• Scrape grease and food scraps from trays, plates, pots, pans, utensils, and grills and cooking surfaces into a can or the trash for disposal. 
• Do not put grease down garbage disposals. 
• Put baskets/strainers in sink drains to catch food scraps and other solids, and empty the drain baskets/strainers into the trash for disposal.

Fact Sheet: Proper Disposal of Fats, Oils and Grease

FOG Brochure Link

Examples of FOG buildup in our system:

Restaurant/Commercial Information

Food Service Establishments (FSE) and other commercial establishments may have grease traps or interceptors that keep grease out of the sewer system. For a grease trap or interceptor to work correctly, it must be properly designed (sized and manufactured to handle the amount that is expected), installed (level, vented, etc.), and maintained (cleaned and serviced on a frequent basis). Solids should never be put into grease traps or interceptors. Routine, often daily, maintenance of grease traps and interceptors is needed to ensure that they properly reduce or prevent blockages. Be cautious of chemicals and additives (including soaps and detergents) that claim to dissolve grease. Some of these additives simply pass grease down pipes where it can clog the sewer lines in another area.

Food Service Establishment Code of Ordinance

• Hydro-mechanical grease interceptors are required to be installed in all new FSE.
• All existing FSE’s may be required to install a grease interceptor at the request of the Director of Public Utilities.
• All grease interceptors shall be located to be easily accessible for cleaning and inspection.
• All grease interceptor and grease traps shall be maintained to ensure proper operation.
• At a minimum, grease interceptors shall be cleaned every 90 days and grease traps once per week.
• All maintenance records for grease removal systems must be documented and stored at the facility.
• All food service establishments must obtain a permit.

To view the Municipal code for Food Service Establishments, click here. 

FOG Toolkit for Restaurants

Link to Survey