FOG Program

What is FOG, and is it a problem?

YES! Fat, oil, grease and grit (FOG) do not mix with water (insoluble) and have a tendency to separate from a liquid solution. When fat, oil and grease are poured down the drain, they stick to the sewer pipe walls creating layers of buildup that restrict the wastewater flow. This problem requires pipes to be cleaned more frequently, causes pipes to be replaced sooner than expected, and causes blockages that can result in sewer overflows.

How does fat, oil, grease and grit (FOG) create a sewer blockage?

Fat, oil, grease and grit when liquid may appear to be harmless since it flows easily down the drain. However, as the liquid cools, the FOG hardens and sticks to the insides of pipes. FOG can partially or completely block wastewater flow, causing backups or overflows. The gritty particles, including coffee grinds, eggshells, aquarium gravel, grain, rice, seeds, etc. get trapped in the greasy buildup, accelerating the problem rapidly.

What products contain fat, oil, grease and grit (FOG)

Fat, oil, grease and grit are natural by-products of the cooking and food preparation process. Common sources include food scraps, meat fats, cooking oils, lard, baked goods, salad dressings, sauces, marinades, dairy products, shortening, butter and margarine, coffee grinds, eggshells, grain, rice, seeds, etc. Anything put through the garbage disposal adds to the buildup.

What can I do to keep fat, oil, grease and grit (FOG) out of the sewer and help prevent a grease related sewer overflow from occurring in my house or on my street?

Everyone plays a role in preventing FOG from damaging our sewer system. The following easy tips can help prevent a sewer overflow in your home or neighborhood.

Fat, oil, grease and grit should NEVER be poured down the sink. Sink drains and garbage disposals are not designed to properly handle these materials.

1. Before washing, scrape and dry wipe pots, pans and dishes with paper towels and dispose of materials in the trash.

2. Pour fat, oil, grease and grit into a disposable container, such as an empty glass jar or coffee can. Once the liquid has cooled and solidified, secure the lid and place the container in the trash.

3. Disconnect, or at least minimize use of the garbage disposal to get rid of food scraps. The garbage disposal chops up food into small pieces, but can still cause a blockage in the pipe. Use sink strainers to catch food items, then empty the strainer into the trash.

Why is it important to properly dispose of FOG?

Sewer system maintenance in neighborhoods that experience sewer blockages and backups due to fat, oil, grease and grit is expensive and can contribute to the amount that customers pay for sewer service. A sewer blockage or backup can also result in expensive repairs to the home.

What should I do if I experience a sewer blockage or overflow?

Call the City of Patterson at 209-895-8060 during regular business hours. After hours, please call 209-895-8000 and select option "9"

Fats Oil and Grease in Pipes
Fats Oil Grease Example

Sewer System Management Plan

On March 5, 2013 the Patterson City Council adopted new City ordinances in accordance with the Sewer System Management Plan Required by the State Water Resource Control Board (SWRCB). Specifically section seven: Fats, Oils, and Grease (FOG). FOG is a byproduct of cooking; FOG comes from meats, fats, lard, oil, shortening, butter, margarine, food scraps, sauces and dairy products. When washed down the drain, FOG sticks to the inside of sewer pipes. Over time FOG can build up and block entire pipes, this excessive accumulation will restrict the flow of wastewater and can lead to serious problems such as Sanitary Sewer Overflows (SSO's). In certain parts of the City, SSO runoff can enter storm drains and flow directly into rivers and natural water ways causing a negative environmental impact on those environments. The ordinances adopted by the City establish a FOG program that will protect the public, in accordance with the SWRCB, by preventing pollutants from entering sewer pipes, natural waterways and facilities. The FOG program will reduce the negative impact of improper disposal through inspections, education, and enforcement of environmental regulations. 

Compliance of the new ordinances will be required by any type of business or establishment where grease or other objectionable materials may be discharged into a public sewage main. Food service establishments are particularly affected because of the amount of grease used in cooking and other food prep work.

Grease-related overflows are costly to clean up, and may expose restaurant customers or employees, food service workers, and others to health risks, or threaten wildlife by going to local creeks rivers untreated. Here are some tips for avoiding grease waste problems.

  • If your restaurant or food service facility produces grease wastes, make sure you have a properly sized grease removal device.
  • Never dispose of grease wastes directly to the sewer, or in the trash dumpster. Contract with a grease disposal company for waste grease pick-up.
  • Maintain your grease trap or grease interceptor on a regular basis. If you are unsure of the proper maintenance frequency, contact your disposal service or the City of Patterson Public Works Department.

Sizing Grease Removal Devices

If you are required to install a grease removal device, it must be properly sized or it may not work. Retrofitting an improperly sized device can be very costly. There are firms that specialize in sizing these devices. If you are planning to install a grease removal device in a new restaurant or food service facility, or to retrofit an existing restaurant or food service facility, be sure to contact the City of Patterson Department of Public Works the proper requirements.