It sounds like a plot for a science fiction film, but lurking beneath the homes of London are colossal-sized beasts which continuously grow in size, some reaching the size of a Boeing 747, and wreaking havoc on thousands of unsuspecting homes.
These are not fictitious creatures. Since 2011 more than a quarter of a million homes have been affected, the same suspects are responsible for each and every case: fatbergs.
What are fatbergs?
It’s no secret that Brits enjoy their fish and chips, roast dinners and the occasional takeaway. We all know fried food is bad for us, so it’s everything in moderation, right? We know they’re bad for us because they’re often cooked in oils, fats and greases which cause heart disease. And we also know how stubborn these fats are to wash away, often needing near-boiling water and lots of washing up liquid.
However, once that concoction leaves the sink it begins to cool, and by the time it reaches the drainage system where it’s cold, the fat solidifies and whatever objects it comes into contact with attaches to it. These fast-growing monstrosities have earned the name fatbergs.
Since 2011, Thames Water has unblocked 200,000 drains and more than 18,000 families have had to deal with raw sewage flooding their homes as a result.
No doubt there’s been small fatbergs, like glaciers, gradually moving through the sewers for decades without major catastrophes. But that’s all changed now. Due to the general use of heavy grease and fats in both domestic and commercial properties, drain problems have risen dramatically, with repair costs soaring.
This is becoming more of a problem in popular London areas, such as Harrow, Ealing and Hounslow, where Thames Water call blockage hotspots. Harrow is at the epicentre with almost 14,000 sightings. There is so much grease and fat coagulating as it flows through the drains, it sticks to the pipe walls as it moves, similar to the clogging of human arteries, and it eventually causes complete blockages.
Effectively, this is a dam-like blockage and the waste water builds up behind it, the drain soon backs up and the system overflows through the lowest gravitational point. Unfortunately for some, the overflow is inside their premises, causing mass destruction and contamination.
In 2015, a 10-tonne fatberg, 40 metres long, broke a Chelsea sewer; it cost £100,000 for each of the four days it took to clear. In 2014, underneath the streets of Shepherds Bush in west London, a fatberg the size of a jumbo jet was discovered; replacing nearly 300-foot of piping in the process, it took Thames Water a week to destroy it. But the biggest so far was jammed under the streets of Kingston in south London; the 15-tonne mass of fat and sanitary products was captured by CCTV in 2013.
Everyone is responsible, including the government: a fatberg was recently found below Westminster. However, these incidents are not just isolated to the City. In Bedfordshire, a fatberg blocked a 300-foot stretch of pipeline. Anglian Water had to bring in specialist equipment from Holland to blow one to pieces, they revealed that dealing with blocked drains costs £15 million a year in higher water bills to both homes and businesses.
There’s no doubt the Victorian-era sewers weren’t engineered to facilitate the amount of waste produced by modern London. But the problem is that London has a combined drainage system, carrying both sewage and rainfall. A sewer system called the Thames Tideway Tunnel, much wider than current drains, has been talked about, but it would take a decade to build following five years of planning. So far the government has failed to give it the go-ahead, and the last time the issue was addressed seriously was back in early 2000.
Thames Water say one in five people flush wet wipes; wet wipes are one of the main non-fat items which help fatbergs grow. With storms and flash floods on the rise, combined with the careless disposing of cooking oils and other household waste, fatberg disasters are constantly in the making and present a serious risk of backed-up sewage flooding homes.
The water company already spends £1 million every month clearing blockages. Fifty thousand homes annually in London fall victim, and other parts of the country report the same story. Really, the only way to spot the problem before it causes damage is to monitor drains by CCTV surveys.
Of course, preventing blockages in the first place is the best solution. Many people probably think they won’t make a difference as they’re only one house or small business, or they think it won’t impact them.