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Fatbergs in drainage systems

Fatbergs often cause a strong reaction in people – the morbid fascination with such a monumental, man-made monster is widespread. A chunk of a particularly humongous one even found its way into the Museum of London recently, demonstrating they are both a marvel to the public and a significant marker of the consequences of modern living in London. So, to feed your curiosity, let’s take a closer look at the fatberg phenomenon.

What is a fatberg?

A fatberg is a congealed mass of non-biodegradable items – such as wet wipes, condoms, sanitary pads and nappies – along with grease, oils and fats. Grease, oils and fat can solidify in the London sewer system and cling to rough sewer linings and any other non-dissolvable items which have been flushed down the toilet. This can cause huge blockages – now known as fatbergs – which can become as solid as concrete.

The fatberg problem

Fatbergs can seriously hamper, or completely grind to a halt, the functioning of the sewage system. A large mass can be problematic as it will slow down the flow of sewage through the pipes, and give a landing point for more waste to accumulate. However, behemoth blockages can completely obstruct sewers, causing chaos for large sections of the city above. From backed up sinks and toilets to road closures whilst the fatberg is cleared, this hulking underground horror can create costly havoc for the day-to-day life of many businesses and homes.

As well as the inconvenience of blockages to the public, fatbergs are a costly problem to clear. Manpower and strong equipment is needed to clear fatbergs and this comes with a constant financial cost. Thames Water estimates it spends around £1 million a month clearing sewer blockages.

Example: Whitechapel, London, 2017

One of the largest ever fatbergs was discovered under Whitechapel in 2017. This enormous blockage was an incredible 250 metres long and roughly 130 tonnes in weight. To give you some perspective, that’s 10 metres longer than Tower Bridge and approximately equivalent to two Airbus A318 aeroplanes in weight!

Workers toiled away 7 days a week to break down the fatberg, chipping away 20-30 tonnes per shift. Power jets and shovels were used to break down the blockage, the majority of which was actually able to be recycled into biodiesel.

How can fatbergs be prevented?

The Victorian sewer system in place under the streets of London just wasn’t designed to cope with the influx of sewage and non-degradable items from the booming population. Preventing fatbergs, which put additional strain on the sewers, isn’t a difficult task though – individuals and businesses just have to be mindful of what they put down the sink and toilet.

Businesses often get the blame for contributing to the emergence of fatbergs due to the amount of grease, fats and oils that they can pour down the drain. Awareness of the negative effects of grease, fats and oils which find their way into the sewers is high, thanks to the publicity around fatbergs. This awareness, combined with suitable training, is vital for ensuring commercial kitchens act responsibly with such waste. Grease traps installed for all kitchen sinks can greatly reduce the amount of fat, oil and grease which finds its way into sewers.

Water UK found that wet wipes make up to 93% of the materials which block sewers, rather than fats, oils and grease. The flushing of wet wipes generally comes from individuals rather than businesses, and so being mindful of what you flush down the toilet can make a big difference to preventing blockages. Basically, if its not toilet paper, don’t flush it.

1st Call Drain Clearance are drainage experts, helping customers across London with a wide variety of drainage issues. Whether you require drain relining, excavation or a CCTV drainage survey, we can ensure your drains run smoothly again as soon as possible. We also offer a 24/7 emergency drain clearance and repair service to ensure any problem can be swiftly solved. Contact our friendly team today with any enquiries.

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