London to soon get its new 'super sewer' which will end Thames pollution blight

A 40 metres (130 feet) long "super sewer" is being constructed in London, which is likely to end the pollution blight of the River Thames. For seven years, the construction workers have been creating the biggest-ever upgrade to the 19th-century sewers of the city, AFP reported.

The existing sewage network of London dates back to the second half of the 1800s when it was built in response to the infamous "Great Stink" and was designed by civil engineer Joseph Bazalgette.

In the year 1858, a combination of a sewerage system which emptied straight into the River Thames and increasing temperatures resulted in London getting engulfed in a cloud of putrid air. The unbearable stench forced the construction of the sewerage system that is currently being used.

However, in recent decades, the growing population of London has led to the overflowing of the sewerage system and led to a flow of raw sewage once again into the river.

Bazalgette's network, which is considered an engineering wonder of the 19th century, used the same pipes for transporting rainwater and sewage, which results in effluent often spilling because of lack of capacity.

Mushrooming population accelerating sewage issues

Taylor Geall, who works at construction firm Tideway which is carrying out the project, speaking to AFP said, "Any time it rains, even a light drizzle, the sewers fill up and pour directly into the river. At the moment, in an average year 40 million tonnes of sewage spills into the Thames completely untreated.”

Even though the old brick-lined sewers, which were constructed between 1859 and 1875, are still in "pristine condition" they are just not big enough in size. "The issue is capacity," Geall added.

The officials had constructed the network when the population of London was just four million compared to today's nine million. Since the size of the population is bound to swell, the need for an upgrade worth £4.3-billion ($5.6-billion) has become critical.

Watch here:

The new "super sewer" which is 25-kilometre (15-mile) long and 7.2 metres in diameter moves from west to east, following the river's curves. When the sewer will be made operational, it will carry sewage only when existing sewers will overflow due to rains.

Overflow points will make it possible for the sewage, which would otherwise have gone into the Thames, to get diverted into the new tunnel, AFP reported.

Around 10,000 people have been working on the sewage project which contains six tunnel-boring machines forged through three distinct geologies - chalk in the east, gravel in the centre and clay in the west of the city.

(With inputs from agencies)

WATCH WION LIVE HERE