Like many other cities in Europe, London is a mix of old and new. Below the shiny skyscrapers and famous landmarks, there’s a Victorian sewer system that was originally built for a population of two and a half million people, but was already serving over four million when it was completed in 1868.
Today, Britain’s capital city is home to more than twice that number, and despite a few upgrades, the sewer system is often overwhelmed.
To stop waste water overflowing into the River Thames, the city is building the Thames Tideway Tunnel — otherwise known as the Super Sewer. Construction of the 25-kilometre tunnel has just been finished. About 70 metres underground and as wide as three double-decker buses, the sewer will carry waste water away from the river to a treatment plant east of the city.
The total project cost is around £5 billion (€5.9 billion), but the Super Sewer is expected to serve London for the next 100 years after it’s completed in 2025.