A complex operation to remove a 120-tonne fatberg from a sewer in Oxford, UK has been carried out by multiple teams across Thames Water.

The fatberg stretched over 1km through the trunk sewer and clearing the congealed fat, oil, grease (FOG) and wipes from the pipe, took two weeks to complete. The pipe’s size and location - 20m deep underground, the high gas levels coming from the fatberg, and the need to maintain Oxford’s wastewater flow, meant the operation required careful planning.

Thames Water says safety was a top priority and measures included securing special permits, safely venting the built-up gases before entry into the sewer, and taking advantage of the dry weather conditions to ensure a safe and controlled operation.

Every year Thames clears 75,000 blockages from its sewer network, at a cost of £18 million. With 60% of sewer flooding incidents caused by sewer abuse the water company says it is important to highlight the importance of only flushing the three Ps down the toilet – Pee, Poo and Paper, and the company's Bin it, Don’t Block it campaign.

This year to date Thames Water has cleared 35,178 blockages due to sewer abuse including:

• 23,556 wet wipe related blockages
• 11,104 FOG blockages
• 518 third-party blockages, such as concrete and other items

Jamie Whitmore, senior project manager at Thames Water said, “Our purpose is to deliver life's essential service, so our customers, communities and the environment can thrive. Clearing this 120-tonne fatberg showcased the dedication, expertise, and teamwork of our people across the business.

"The scale of the blockage and the conditions underground made this activity challenging and I’m incredibly proud, we were able to maintain the safety of our teams whilst continuing to provide wastewater services for Oxford. This is a powerful reminder of why it’s so important to only flush the three Ps down the toilet, so we can continue to keep our sewers flowing and reduce the risk of flooding, blockages and pollutions.”