This statistic was revealed by the Consumer Council for Water (CCWater) in a message to customers offering top tips to reduce sewer blockages.
CCWater’s research showed that Thames Water had the highest number of blockages in the last year with 50,200, which is 12,700 more than any other company.
Over two thirds of sewer blockages are caused by inappropriate items and substances being put down the sink or toilet.
The worst problems are being caused by fat, oils and greases being poured down sinks and wet wipes, tissues and nappies being flushed down the loo.
These build up to create fatbergs and other blockages that cause thousands of homes to be flooded with sewage every year.
Among more unusual things found down sewers last year by water companies were a sofa, a motorbike, half a Mini and a prosthetic leg.
According to CCWater’s research less than half of water customers know what is safe to put down the sink or drain, or flush down the toilet.
CCWater policy manager Steve Grebby, said: “Seeing your home flooded as a result of a blocked sewer or drain can be devastating.
“But the good news is we can all play a part in reducing the risk of this happening by thinking more carefully about what we pour down the sink or flush down the toilet.”