News Details

Fats, Oils and Grease

The discharge of fats, oils and grease (FOG) to the sanitary sewer system is an important environmental and public health issue. FOG builds up in sewer lines and restricts the capacity of the pipes.  Attempts to keep the sewer collection system flowing is very costly and time consuming.  Sanitary Sewer Overflows negatively impact public health and the environment by causing backups and discharge of raw sewage into streets, storm drains, and creeks.  The U.S. Environmental Protection Agency and the State of California require municipalities to take steps to reduce sewer overflows,  the majority of which are caused by grease blockages. 

In addition, federal and state regulations require reduction of other pollutants to the storm and sanitary sewer systems, including trash and harmful chemicals.  These requirements are addressed in Palo Alto's Sewer Use ordinance.

What we can do to help:

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 (or recycling where available)

  • 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

  • Speak with your friends and neighbors about the problem of grease in the sewer system and how to keep it out. Call us at (650) 329-2598 if you have any questions


All Food Service Establishments (FSEs) must be in compliance with the Palo Alto Municipal Code (PAMC).  Section 16.09.075, contains specific requirements applicable to FSEs.  If you need help interpreting the code, suggestions for meeting the requirements, or help sizing and selecting a Grease Control Device (GCD) please call the Regional Water Quality Control Plant at (650) 329-2598

  • The discharge of fats, oils and grease (FOG) is prohibited to any draining piping, public or private sanitary sewer, storm drain, or onto any land, street, public way, or any waterway.
  • Food Grinders (garbage disposals) are not permitted.
  • Grease Control Devices (GCDs) are required for all FOG generating facilities.  See the Sewer Use Ordinance for requirements for sizing, connections, etc.  Label kitchen drain fixtures (non-restroom) as to whether they drain to the GCD or the sanitary system.
  • GCDs shall be maintained regularly according to the manufacturer's specifications.  GCDs shall be pumped out by a permitted waste hauler. The frequency of pump-outs shall ensure effective operation of the GCD and compliance with the discharge prohibition.  The frequency may need to be greater than the minimum.  The minimum frequency is determined by the size and type of the GCD (every three months for grease interceptors greater than 100 gallons, every month for grease traps, and every six months for automatic or mechanical self cleaning GCDs).  Maintenance frequencies may be modified by the City.  Maintenance logs shall be kept onsite and provided to City Staff when requested.
  • Best management practices (BMPs) to prevent FOG discharges shall be implemented. A poster is available for posting in various languages to remind employees on how to prevent FOG discharge. BMPs include:

    • Removing food waste from preparation and service items prior to washing and disposal in the trash or food scrap container (dry wipe pots, pans, and dishes before washing)
    • Installing drain screen in all sinks, drains, floor drains, floor sinks, dishwashers, etc. Clean screens frequently into the trash or food scrap container.
    • Cleaning water from floors, floor mats, exhaust hoods, large kitchen equipment, trash, recycling, tallow containers, or other dishwashing not done in a dishwasher, should be directed to the GCD prior to discharge, including outdoor cleaning.
    • Maintain exhaust hood and vent grease collections devices, including those on roofs, in hoods and removable filters to prevent spills and overflows.
    • Dispose waste oil/grease in a tallow receptacle that is kept free of spills, and closed with a lid.
    • Prevent stormwater pollution by keeping waste containers and surrounding area covered and clean and free of FOG and food residue, debris and leaks.
    • Cleaning up spills using dry methods first (sweeping, rags, absorbent material that are disposed in the trash), then mop and bucket. Mop water is discharged through the GCD.
  • Keep employee training records, including employee signatures for attendance and understanding of the requirements, on site for inspection.
  • The City of Palo Alto ordinance restricts food vendors from providing prepared food in disposable food service containers made from expanded polystyrene or non-recyclable plastic.  See Polystyrene Restriction Ordinance in Effect for more information on the ordinance and alternative take-out containers.
  • The City has a full time inspector for restaurants who will visit the facility to ensure compliance.
  • Please call the Regional Water Quality Control Plant with any questions: 650.329.2122.



Last Updated June 26, 2014