Fat,Oil and Grease Programme

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What are Fats, Oils and Grease (FOG)?

FOG stands for ‘fats, oils and grease’ and originate from food products such as butter, lard, vegetable oils, animal fats, meats, sauces and dairy products. They are generated during the preparation of food and from any cleaning/washing up processes. 

FOG causes a problem when it is washed down the drains, either during food preparation or in the washing up operation. When it cools it will congeal and accumulate in pipelines, thus eventually blocking the pipe.

Drainage maintenance records indicate that FOG is a serious problem in areas where there are concentrations of Food Service Establishments (FSE) such as pubs, restaurants, hotels, takeaways, convenience stores, etc. This is line with international experience that identifies FOG as a major problem in managing both the drainage network and wastewater treatment plants. Dublin City Council commenced a programme to control the discharge of fat, oil and grease to the public sewer system in January 2008. Since January 2014 Irish Water has taken over responsibility for the FOG Programme.

Under the FOG Programme, every food service establishment is required to apply for a licence to discharge trade effluent under Section 16 of the Local Government (Water Pollution) Act 1977.

  • For an application form, please see  www.water.ie/tradeeffluent
  • Once a trade effluent licence has been granted, each licensee must comply with the conditions as set out therein. Typically these conditions include: the installation of an appropriately sized grease trap, regular maintenance of the grease trap, the proper disposal of waste oil and a limit on the amount of FOG discharged to sewer to 100mg/l.

If you have any questions or seek advise on how to protect your drains from FOG please the Irish Water website at https://www.water.ie/for-business/trade-effluent/fats-oils-and-grease/


For more information visit https://www.water.ie/contact-us/ or email fog@water.ie