Make sure your festive food isn’t a costly pain in the drain

Fat, oil and grease major cause of sewer blockages in Wales.

2,000 blockages a month costing £7million per year.

Blockages lead to human misery and every year flood hundreds of homes.

Tipping turkey fat, gravy and other leftovers down the plughole this Christmas could be a recipe for disaster, Welsh Water and the Consumer Council for Water (CCWater) is warning households and restaurants across Wales.

Welsh Water and the consumer watchdog are urging people across Wales to stop and think about what they pour down the sink, especially over the festive period when sewerage companies often report a rise in fat, oil and grease clogging up the sewers.

Blocked sewer pipes can increase the risk of homes and businesses being flooded with sewage. Also, greasy leftovers can clog up a property’s drains, landing the householder with a costly callout charge for someone to clean up the mess.

Welsh Water’s director of waste water services, Steve Wilson, said: “Fats, oils and grease from homes and businesses can cause major problems to drains and sewers. They may not appear harmful, but when they pass through the drainage system they congeal, harden and stick to the inside of pipes which leads to blockages. Every month we deal with 2,000 blockages which cost us over £7 million pounds a year to clear.

“With the collective support of enough people, Welsh Water will be able to reduce the blockages, floods and pollution that cause so much distress. Reducing these blockages will also mean that our not-for-profit company will be able to invest more in other improvements on behalf of our customers. Customers can find out more at

Steve Grebby, CCWater’s sewer expert, said: “Imagine waking up one morning over Christmas to find your presents swimming in sewage. It’s a horrifying thought and that is why we all need to do our bit to keep our sewers and drains flowing freely.”

“There are lots of simple ways to safely dispose of leftover fat or grease, including letting it cool in a container before scraping it straight into the bin. It might cost you a little more time, but it could save you a lot of money.”

Running the hot water tap and soaking greasy pans in detergent is not the answer as the grease and water will eventually cool down and block drains and sewers. It’s much safer to keep a ‘fat-trap’ or container in your kitchen to collect waste before emptying it into the bin.


  • Welsh Water spends around £7 million a year clearing avoidable blockages in sewers – the cost is passed onto customers through sewerage bills.
  • Around two thirds of sewer blockages on Welsh Water’s network are caused by inappropriate substances like fat, oil and grease (FOG), wet wipes and sanitary products being flushed down the loo.
  • Last year Welsh Water had to clear a major ‘fatberg’ blockage from underneath a busy Cardiff street.
  • The build-up of fat, oil and grease is indirectly responsible for many cases of sewer flooding and pollution of rivers and streams.
  • If we all take care not to tip our greasy leftovers into the sewerage system, the number of customers affected by flooding and the impact on our environment will be significantly reduced.

Flooding facts:

  • Drains from the home are normally no wider than four inches (100mm).
  • If there is a blockage or fault in your private drain, you will need to hire a drainage contractor to clear or repair it. Sewerage companies are only responsible for maintaining public sewers.
  • If sewage has flooded your property from a public sewer, the company should send someone to help clean up your home as quickly as possible.
  • You are entitled to a rebate off your annual sewerage bill to cover damages to the inside of your home caused by flooding from the public sewer.
  • Don’t forget to check whether your household insurance covers damage from sewer flooding.

Categories: News, Wales