New ‘super sewer’ to end Thames pollution to be tested in 2024

For seven years, thousands of laborers and engineers worked under London and the Thames on the construction of a colossal 25-kilometer tunnel: modernizing the 19th-century sewers, it was possible to finally stop the massive discharge of sewage. in the river. With a diameter of 7.2 meters, the tunnel follows the curves of the River Thames from west to east. this “Super sewerCalled in the UK, it will be tested in 2024 and fully operational by 2025.

It was the biggest modernization of London’s sewer system since the second half of the 19th century and was designed by the infamous ‘Joseph Basalket’ at the time.Great stenchIn July and August 1858, a combination of high temperatures and sewage flowing directly into the Thames engulfed the city in a cloud of putrid air. But in recent decades, the sewerage capacity to cope with the British capital’s growing population has led to sewage flowing back into the river.

40 million tons of sewage is discharged every year

Joseph Basilket’s sewage system, a masterpiece of 19th-century engineering, carried both sewage and rainwater, so the former mostly flowed into the Thames. “Every time it rains, even a light drizzle, the drain fills up and flows straight into the river.Taylor Giall of Tideway, the construction company behind the project, explains. “An average of 40 million tonnes of sewage a year flows into the Thames without any treatment».

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The old brick drains are still in good condition, but they are inadequate. The network was built when London’s population was four million, today it is nine million. The modernization will cost 4.3 billion pounds (5.02 billion euros).

The new tunnel will only carry sewage if the existing sewers are full. Overflow points would allow waste water that would have flowed into the Thames under the current system to be diverted into the new tunnel. “We intercept and remove 95% of leaks», confirmed Taylor Keel. «The river won’t look too different when we’re done, but it will provide a much healthier environment for the fish, marine mammals and birds that live there.».

The final stages of construction of the mega-project are underway amid controversy over the water sector, which was privatized in 1989 and accused of underinvestment in its networks over the long term. According to the Government Environment Agency, rivers and coastal areas across the UK saw an average of 825 sewage spills a day last year.

Beach closures

Many beaches on the Isle of Wight, on England’s south coast, had to be closed during last summer’s heatwave due to high levels of bacteria in the water. Surfers Against Sewage recently released a list of 83 beaches across the country to avoid due to sewage spills.

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Water companies, along with other energy and waste operators, will face unlimited fines for polluting activities, the government announced this week. London-area water management company Thames Water, which serves 15 million customers, was fined £3.3 million in early July for polluting waterways. It is almost 14 billion pounds sterling (16.3 billion euros) in debt. Its customers are “Super sewer» By direct debit from their invoices.

According to the PA news agency, Thames Water has already paid £32.4 million in fines between 2017 and 2021 for pollution incidents in the Thames Valley and south-west London among other regulator cases. For Matthew Frith of the environmental organization London Wildlife Trust, the new sewer will bring “Contribution majeureFor the restoration of the River Thames. But he says that the problem elsewhere in the country will not be solved.