FOG FAQs

The Costa Mesa Sanitary District is the owner of the public sewer system serving the City of Costa Mesa and is responsible for keeping the sewer system functioning properly. The State of California has required the District to implement a comprehensive Fats, Oils, and Grease (FOG) Control Program to prevent blockages in the sewer lines that can cause overflows and spills (FOG Program). These sewer spills end up in the storm drain system and waterways and are a significant cause of ocean water pollution.

Instead of pouring used cooking oil down the drain, do the following to prevent sewer backups and recycle your FOG: pour the cooled FOG into a compostable bag and place it in your Organics Cart for curbside collection OR pour the cooled FOG into a sturdy container (such as a milk jug or coffee tin) and bring it to the Orange Coast College Recycling Center, located on Adams Avenue between Harbor Boulevard and Fairview Road.

When fats, oils, and grease are introduced into the sewer, they are usually warm and free flowing.  However, shortly thereafter, they cool and harden and adhere to the pipe wall.  A FOG buildup will eventually cause a sewer backup.

FOG is the number one cause of sewer line problems and the State Water Resources Control Board has mandated through an Order that all sewer agencies in the State of California have a comprehensive FOG reduction and management program.

FOG is a by-product of the cooking process and may be discharged into the system by restaurants, institutional kitchens, and residences.

CMSD's FOG Program review of food service establishment plans is required to ensure that the new (or modified) facility meets current FOG Program rules and regulations.

Yes. Each food facility in the District’s service is issued a Food Service Establishment Wastewater Discharge Permit that identifies the general requirements of the CMSD FOG Control Program. The permit will also identify any special requirements that apply uniquely to an individual establishment.

A grease interceptor is required if your establishment is: 1) a new construction of a food service establishment, 2) an existing food service establishment undergoing a change in ownership, 3) an existing food service establishment undergoing a change in operations, or 4) an existing food service establishment undergoing a remodel that includes under-slab plumbing, increased seating, increased kitchen area, or changes to the size or type of food preparation equipment.

Grease interceptor sizing is based on the drainage fixture units (DFU) connected to the grease interceptor, pursuant to the current California Plumbing Code (CPC), table 10-3.

All potential grease bearing fixtures and drains (cooking equipment drains, pot sinks, 3-comp sinks, mop sinks, dishwasher pre-rinse sinks, prep sinks, floor sinks, floor drains) in the food preparation, cooking and cleanup areas of the facility are required to be connected to the grease interceptor.

The drainage from automatic dishwashers should not be connected to the grease interceptor (Note: the dishwasher pre-rinse sink must be connected to the interceptor).

The grease interceptor configuration must provide access for maintenance and inspection of the Inlet, Outlet and Baffle (center wall) tees and should include a sample box. Depending on the grease interceptor size and manufacturer, the grease interceptor may require three (3) access openings (excluding the sample box) to provide the required access. Consult with your interceptor manufacturer to identify a grease interceptor configuration that meets these requirements.

Yes. Soon after your facility begins operations, a CMSD FOG Inspector will conduct an inspection of your facility to assist you with your understanding of the Program. Routine FOG inspections are then conducted on a regular basis to ensure continued compliance with the FOG Program rules and regulations