Massive 100-Ton Fatberg Cleared from London Sewers in Monthlong Operation

In a major sewer cleanup operation, a team of water engineers from Thames Water have spent the past month blasting and chiseling a massive 100-ton fatberg loose from under the streets of Feltham, west London. The blockage, equivalent in mass to 8 double-decker buses, was discovered 10 meters below street level and consisted primarily of wet wipes compacted into a fibrous and gelatinous mass, combined with congealed fat, oil, and grease.

The Feltham fatberg fiasco has prompted Thames Water to circulate details of the mammoth cleanup job as part of a month-long national campaign to raise awareness of how substances and items tipped down drains can negatively impact rivers, seas, and the wider environment. The company says it spends £18 million clearing 3.8 billion wipes from its network every year, with over 28,000 rag blockages cleared so far in 2025 alone.

While the government has announced plans to ban plastic-containing wet wipes, Thames Water's creditors are also asking the industry regulator for leniency on pollution rules, arguing the scale of upgrades needed across London and southeast England after years of neglect would make it impossible to comply more quickly. The fatberg fiasco highlights the ongoing battle against the growing problem of sewer blockages caused by the improper disposal of fats, oils, grease, and non-biodegradable items.