Recycling Grease

Nationally, forty-three percent of all sanitary sewer overflows are caused by blocked sewer mains. These blockages can cause an overflow into local streams, yards and structures. Overflows are detrimental to the environment, distressing to local residents and costly to the city in insurance claims and regulatory fees.

Locally, blockages are primarily caused by the build-up of hardened grease and oils. Grease enters the system from many sources, including individual households. As expected, the largest contributors are from local food service establishments, which include restaurants, grocery stores, nursing homes, etc. The grease and oil enter the system in a liquid state suspended in wastewater from dishwashers and wash sinks. As the suspended grease cools it solidifies, accumulating into a hardened mass that adheres to sewer pipes and equipment.

By establishing a schedule of regular inspection and cleaning, the Prattville Wastewater Division has made overflows a rare occurrence. These regular inspections reveal that mains serving concentrations of restaurants and hotels accumulate solidified grease at a faster rate than the system as a whole. Prattville’s building code requires the installation of grease interceptors (shown in the diagram below) or traps by any food service establishment. Better enforcement of the building code over the last decade has ensured that the facilities are present to trap grease before it enters the system. These interceptors are inexpensive to operate, but require periodic cleaning to remain effective. The City of Prattville currently does not have an ordinance allowing city staff to inspect grease interceptors or enforce their periodic cleaning and maintenance



The Prattville City Council passed an ordinance on May 1, 2007 that requires the use of grease interceptors by food service establishments, require the periodic cleaning and maintenance of interceptors and provides city staff with a mechanism to monitor and enforce periodic cleaning. The ordinance applies to all food service establishments. It applies to all new construction or renovations. All existing establishments were given a year from the date of passage to comply. The ordinance also contains provisions for establishments located where the standard grease trap would be difficult to install.

Implementation and enforcement of this ordinance, combined with the Wastewater Division’s existing inspection and maintenance schedule, has reduced the possibility of sanitary sewer overflows. At a minimum, implementation has reduced the time devoted to grease removal from the system.

*NOTE: Grease accounts for 90% of the blockages in sewer lines. Residents, please do not dump grease down your toilets or drains. It doesn't just clog City sewer lines; it also causes issues within the pipes that run throughout and from your residence.