London's iconic River Thames is set to undergo a major transformation with the construction of a new drainage system known as the Super Sewer. The £4.5 billion project aims to upgrade the city's outdated Victorian drainage network and tackle the issue of raw sewage that spills into the river. 

Spanning 15.5 miles (25 km) and reaching depths of up to 65 meters, the Super Sewer will connect to the existing network and have the capacity to store approximately 1.6 million tonnes of effluent. By capturing overflow during rainy days, it will prevent tens of millions of tonnes of raw sewage from polluting the river each year.

The project, scheduled for completion by 2025, involves the use of giant boring machines working 65 meters below the city. Once finished, the central tunnel, lined with concrete, will be wide enough to accommodate three double-decker buses. It will transport waste from Acton in the west to the Beckton treatment works in the east.

The population of London has soared to nearly nine million people, with projections indicating it could reach 16 million by the mid-2100s. To safeguard the river for future generations, the Super Sewer represents a vital step in ensuring the cleanliness and hygiene of the Thames.

Joel Harland, a civil engineer involved in the project, emphasizes the importance of upgrading the city's infrastructure to protect the river. He highlights that people often overlook what happens to their wastewater and that building projects like the Super Sewer shed light on the mechanics behind a functioning society.

With the Super Sewer, London is taking a significant stride towards a cleaner and healthier River Thames, ensuring a sustainable future for the city and its residents.