The Whitechapel fatberg was 250 metres of impacted waste that constipated London’s sewage system last year. A tiny portion has just been put on display in the Museum of London after a long, conscientious drying period. It hardly smells at all now. But does such an intrinsically disgusting artefact belong in a museum? Instinctively the answer seems to be no: we should have kept it in the ground.

On second thoughts, the matter is more complicated. The fatberg is not on show as the ultimate conclusion of the line of thought that began a hundred years ago with Marcel Duchamp’s urinal. Although there are people who might argue that conceptual art all finds its natural home in the fatberg, not everything in the sewers is conceptual art. Some of it is just sewage. Some is stuff that should not be flushed away – wet wipes and sanitary products – and much is just used cooking fat and food scraps. This fatberg was found under Whitechapel Road, in a district full of restaurants in the East End of London, but others have been found all over the city. No one, it seems, is too posh to flush.

Placing a small and dehydrated portion in a glass case is an excellent way for the museum to bring into the light some of the hidden processes on which any large modern city runs. The lives saved by functioning sewage systems are difficult to quantify, but in the latter half of the 19th century life expectancy in the UK went up by four years, or more than 10%, without the benefits of modern medicine or proper nutrition for the urban poor, and almost all of that must be accounted for by cleaner water.

Throwing away nutritious – if hardly delicious – cooking fat is a habit of prosperity, as are the wet wipes, and even the sanitary products which give body to the fatberg. Life is better for all these small innovations, and a life where there is food left over to be thrown away is better than one which is confined by hunger. But the problems of affluence accumulate. What creeps under our cities is only a small fraction of the waste generated by the private conveniences of our life above the streets. Outside the sewers, our lifestyles generate rubbish which is much less offensive to our eyes and noses than the fatbergs, but much more damaging to the planet and to the people who have to dispose of it. Most of the matter in the fatbergs can in fact be usefully recycled. The fat itself makes biodiesel fuel, and – in a pleasing circle of recycling – some of it ends up fuelling London buses and taking pollution off the streets.

There are many ways that a museum can enrich the city that it sits in. Art museums obviously do so in ways entirely different from museums of technology or history. But what all of them have in common is that they make us glimpse possibilities beyond the quotidian and – improbable as it might seem – the fatberg delivers, beyond the simple pleasure of gawking, an unforgettable reminder that the price of affluence is constant effluent.