LONDON (AP) — It may look like an iceberg, but there's nothing cool about it.

Utility company Thames Water says it has discovered what it calls the biggest "fatberg" ever recorded in Britain — a 15-ton blob of congealed fat and baby wipes the size of a bus lodged in a sewer drain. Thames Water says the mound of "wrongly flushed festering food fat mixed with wet wipes" was found under a road in the London suburb of Kingston.

Thames Water deals with fatbergs all the time. But the company said Tuesday it was sharing news of the massive lard lump in hopes that customers will think twice about what they dump down the drain.

The company says untreated fatbergs cause flooding and backups.