FOG is an acronym for fats, oils and grease. FOGs create a significant problem for the wastewater treatment plant and the pumping stations, the wastewater collection system, and the local sanitary sewer user. FOGs discharged by residential, commercial, institutional and industrial users account for approximately 25% of all sanitary sewer blockages in the City of Moberly, with numbers similar around the country.
Fats, oils and grease are often washed into the residential plumbing system through the kitchen sink. Fats, oils and grease have poor solubility in water. This means they separate from the liquid.
When FOGs are poured down the kitchen drain, they cool down, according to the surrounding water temperature, and then separate. FOGs stick to the inside of sewer pipes from the point of entry into the sewer system until it reaches its final destination, the wastewater treatment plant. As the FOG travels through the system, it builds up, one layer after another, on the inside of the pipes. This build up reduces the pipe’s carrying capacity and will, over time, block the entire pipe.