Depolluting the river Thames

Résumé du document

Let's travel to somewhere almost near by, I'm sure some of you have actually seen it with your own eyes. I'm talking about the river Thames, which is the longest river in England, with almost three hundred fifty kilometers long...
As a result, you won't find it very surprising if I told you that in 1957, the Thames was so polluted that it was declared biologically dead by the Natural History Museum.

Extraits

[...] They have more or less of an ability to move from a compartment to another, leaving the air to contaminate the Thames's waters. This makes industry our first cause of pollution. Steam Machine Victorian's era pollution In your opinion, what else could have polluted the Thames? B. The second cause of pollution Well, the Londoners themselves, that discharged sewage directly into the Thames for centuries. It probably had had a real impact on the river's health state since the Middle Ages. [...]

[...] Some of those factories even closed or retrained to less polluting activities. Actually, Tate Modern, London's Modern Art Museum, is a former power station (not necessarily polluting but a good example of London's industrial landscape renewal). Last but not least, our third source of pollution, plastic waste, has not been solved yet. A campaign called “Cleaner Thames” was launched in September 2015 to fight it. I will conclude by giving you some kind of an underground view of London and the Thames. [...]

[...] The thing with single use plastics and plastic bags is that even when they're picked up by associations, they keep being thrown away by consumers and they still end up washed up on the beaches. So far, we've seen three different sources of pollution affected the river Thames: industrial waste, waste water, and plastic waste. Let's now move on to how those were fought to bring the Thames back to life, in both senses of the word: there are now a hundred twenty-five species of fish in the river, while they were almost none in the fifties. II. [...]

[...] I hope you would like to find out how they managed to clean efficiently such a great amount of fluvial water: that's actually the topic we're going to explore during this presentation. I. The River Thames pollution A. The first cause of pollution First of all, I'd like to go back in time for a while, to try to get the measure of how polluted the Thames was. Then we'll discuss the water treatments that were used to make it the cleanest urban river worldwide. [...]

[...] In 2014 they finished building a new sewer under the Thames, so huge it was called “super-sewer”. It took three years with four thousand people working on it, to dig more than six kilometers of galleries and build the shaft connected to it. This project really took life because waste was endangering the Thames. It cost England and London several billion pounds. This makes us realise that the great work that was achieved to save the Thames is not applicable to every other urban river worldwide. Poorer countries probably can't afford such a gigantic rehabilitation project. [...]