Until July 2018, the London tourist board can add a congealed mass of fat and wet wipes hauled from the city’s sewers to its list of attractions. The Museum of London has put a chunk of the now famous Whitechapel Fatberg on display. Before it was removed in November last year, becoming a media sensation, it was one of the largest specimens ever found of a phenomenon that highlights the problems looming under the feet of city dwellers around the world.
Fatbergs are massive blocks of waste cooking fat and “disposable” sanitary products which block sewers. Wet wipes, nappies, sanitary towels and condoms all contribute to the fatberg phenomenon. Dislodging them isn’t cheap: Thames Water, the company which handled the Whitechapel Fatberg’s excavation, spends around £1 million (US $1.3 million) every month removing them.
The problem isn’t unique to London: from New York to New Zealand, fat is blocking drains and putting the health of city dwellers at risk. Blocked sewers can overflow, pollute the water supply, and spread harmful bacteria. But while fatbergs fill the headlines and exhibition cabinets, the hype masks a serious problem: the crumbling infrastructure and lack of funding for the world’s sewers.
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Captain, fatberg ahead!
The problem isn’t new, but pressure on urban sanitation systems is mounting thanks to rural to urban migration and rising population figures. From 1960 and 2015, the world’s urban population has grown from 33% to 54% of the total.
Lifestyle changes have also contributed. The rise of fast food has multiplied the volume of leftover fat poured down the drain.
Modern habits are ruining ageing sewers. “In cities like London, the water services are Victorian,” said Professor Richard Ashley, Emeritus Professor at the Department of Civil and Structural Engineering at the University of Sheffield. “Although they’ve been very effective, they have vulnerability to stuff like fatbergs, because that level of fat, oil and grease has never been taken into sewers before.”
The other main culprit is wet wipes. Here again, modern behaviour has contributed to the problem. While wet wipes used to be reserved for children, in the last decade more adults have started to use them: the size of the global market is estimated to reach $13.5 billion by the end of 2018. Once used, they’re mistakenly flushed down the drain.
“Even though some of these things are marketed as flushable, they’re not biodegradable,” said Dr Sharon George, environmental sustainability lecturer at Keele University. “They go into the drains, and they clog.”
Many cities are trying to stop the ingredients for a fatberg reaching the sewers in the first place. In Dublin, fast food restaurants are now required to fit grease traps to capture fat before it disappears down the drain. Inspections hold restaurants to account. Elsewhere, such rules aren’t so stringently enforced. In London, despite regulations holding premises liable for costs incurred clearing blockages, it’s hard to attribute blame. In 2017, after Whitechapel’s fatberg calamity, it was revealed that 90% of London restaurants don’t have grease traps.
Public information campaigns also have a role to play. Ireland’s Think Before You Flush campaign surveyed Irish households’ flushing habits, and lists what should and shouldn’t go down the drain. Thames Water’s Bin it Don’t Block it campaign encourages the public to bin, rather than flush, wet wipes and other plastic products.
Elsewhere, cities are getting more creative. In the North East of England, one water provider uses a cartoon character, Dwain Pipe, to encourage people to keep plastics out of the sewage system. The campaign comprised television adverts, posters, flyers, school visits and an app. The company analysed their data to work out where blockages were occurring before targeting those communities with adverts.
It’s working. Sewer blockages fell by 10% overall in the region and by double that in the worst affected areas.
Key to the strategy is reaching people early. The company sent a professional youth theatre to the area’s schools to perform a play about what can and can’t go down the drain. Encouraging children to change their behaviour helps to tackle the problem in the long term, and encourages them to influence their parents.
Blocked cash flow
Fatbergs are just a symptom of a larger issue, namely that city dwellers aren’t paying enough attention to their water systems and sanitation. A funding crisis is looming.
In a report for the OECD in 2006, Ashley and a colleague argued that the expenditure on updating water systems is falling far short of the significant investment it needs by 2030. Little has changed since. Without money to radically improve our waterways and sewers, the number of blockages will only increase.
According to Ashley, the market of water suppliers is dysfunctional. Companies are paying large dividends to shareholders that should be going to maintaining ageing sewers. And, he argues, the competition to charge consumers as little as possible is shaping the way we think about our sanitation systems.
The convenience and cheapness of our water supply encourages its misuse, he argues: “If you charge people the true cost then it makes it valuable”. Making people pay for irresponsible waste disposal practices might be key to steering clear of the fatbergs ahead.
(Picture credit: Flickr/Matt Brown)