A supersized fatberg in Birmingham that weighs around 300 tonnes may take until June to clear.
Water provider Severn Trent said it was probably one of the biggest ever blockages it had dealt with, and its employees were working around the clock to remove it from Hodge Hill.
It is estimated to be one metre high and over 1000 metres in length and is formed mainly of oil, grease and non-biodegradable materials like wet wipes and nappies.
Severn Trent, which compared the fatberg to the weight of 250 family cars, added its true size will not be known until it is removed.
Severn Trent operations manager Scott Burgin said: “It’s a massive project and it’s not resolved yet.
“This giant mass is the result of everyone occasionally washing and flushing the wrong things down the drains, and not realising the impact that it’s having.
“The problem is that unlike toilet paper, wipes and other unflushables including nappies and sanitary products don’t break up or dissolve, so they easily get stuck in drains and sewers and then attach onto cooking oil and grease to create a fatberg.
“Our advice is to always leave leftover cooking fat to cool, before disposing of it in the bin and to stick to only flushing the three P’s (pee, poo and toilet paper) and bin anything else.
“These relatively small changes can make a big difference and hopefully avoid any future fatbergs.”
Severn Trent said it had been called out to thousands of blockages across the Midlands in the last year, of which three quarters were caused by people misusing the sewer system.
It was alerted to the fatberg by sewer sensors which monitor for rising water levels.
If an alert is triggered, a team of engineers respond to investigate and clear any blockages forming before customers are impacted.
Burgin added: “We’d like to apologise to any customers who might be affected by our work and thank the community for their patience and understanding.
“We’re working as quickly as we can to resolve this problem and get everything back to normal as quickly as possible.”
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