Much less sewage flows into the river in London

“A new sewer tunnel beneath London has dramatically reduced sewage overflows into the River Thames, according to a report from Thames Water, London’s primary water utility. In 2025, the tunnel’s first full year of operation, around 3 million cubic meters of sewage-contaminated water entered the river. That’s 86 percent less than the 2020–2023 baseline average, and 81 percent less than the volume discharged in 2022, a year with a similar level of rainfall to 2025,” notes Human Progress.

“The first annual Tideway Benefits Report has revealed significant improvement in river health following the opening of the super sewer in 2025.

Storm overflows to the tidal Thames have been successfully reduced by 86%, compared to pre-Tideway levels, as the operation of this significant asset is transferred to Thames Water from Tideway, the company set up to deliver the project.

The findings mark a new chapter for the River Thames and signals that London’s principal waterway, which was once declared biologically dead in the late 1950s, is firmly on the road to recovery.”

Other major rivers have also gotten much cleaner, For over a century, the river that flows through Paris (the Seine) was so dirty that it was illegal to swim in it. But now, it has become so clean that swimming in it was recently legalized by the City of Paris.

Fish have returned to the once horrifically polluted Chicago River. Many fish in the Hudson River are now safe to eat.

In Germany, a sludge-filled river became a thriving ecosystem: “For more than a century, Germany’s Emscher river carried sewage and industrial sludge through the Ruhr, earning a reputation as an open sewer. Now, after a massive cleanup, the river is becoming a thriving ecosystem once again.”

“In the early 2000s, a population of flamingos began making the Venetian Lagoon their winter home. Since then, the annual population peak has risen to nearly 24,000 birds,” reports The Doomslayer.  The lagoon is now one of the most important wintering spots for flamingos, says an ornithologist quoted by The Associated Press.