A massive 100-tonne fatberg has been successfully cleared from a sewer in west London after a month-long removal effort by Thames Water. The enormous blockage, buried more than 10 metres (32 feet) beneath the streets of Feltham, was described by the utility company as one of the most complex operations its engineers have faced.
The solid mass comparable in weight to eight double-decker buses was made up primarily of congealed fat, oil, grease, and a dense tangle of wet wipes. Engineers had to access the sewer through a large manhole chamber, wearing protective gear and using gas monitors for safety. The team blasted, chiselled, and vacuumed the hardened waste along 125 metres (410 feet) of pipe before craning the debris into skips for disposal at a landfill site.
Alexander Dudfield, Thames Water’s engagement lead for network protection, described the clearance as “hugely complex” and emphasized the ongoing challenge of sewer blockages across London. “Some of the biggest fatbergs we deal with can weigh as much as 25 elephants,” Dudfield said. “But most blockages actually happen in local pipes often narrower than a mobile phone and are usually caused by a few households. When these get blocked, sewage has nowhere to go and can end up overflowing into roads, rivers, or even homes.”
The Feltham fatberg’s removal follows a recent cleanup near Hammersmith Bridge, where Thames Water joined forces with the Port of London Authority and environmental charity Thames21 to remove a thick layer of wet wipes that had compacted into sludge on the riverbed.
Wet wipes remain one of the leading causes of sewer blockages in the UK. Thames Water reports clearing about 75,000 blockages each year costing around £18 million in operations and removing approximately 3.8 million wipes from its network annually. So far this year, the company has dealt with 28,899 rag blockages (mostly wipes), 14,810 fat, oil, and grease-related blockages, and 686 caused by construction materials such as concrete.
The company continues to urge the public not to flush wipes, grease, or other non-biodegradable waste down toilets and drains. As Dudfield noted, “Every fatberg starts at home. Small changes in what we flush and pour away can stop these giant blockages from forming and prevent devastating consequences for our communities and waterways.”