This week was the 150th anniversary of the ‘great stink’, when the River Thames was so disgusting that Parliament was forced to abandon the House of Commons and move to Oxford. This led directly to the building of the London sewer system by Joseph Bazalgette and started a process of cleaning up the Thames that has continued till today.

I went to an event to celebrate this earlier this week. I chatted to Peter Ackroyd, the historian of London and author of ‘Thames – Sacred River’. He said that until the second half of the 19th century, Londoners were still drinking water from the same portions of the Thames that open sewers were discharging into and typhoid and cholera were rife. He felt that Bazalgette was responsible for the most important environmental and public health project in our nation’s history.

This is a very positive story about how we can tackle environmental and social problems through using ingenuity and investment. Gone too are the great smogs of last century and the turds that used to decorate our beaches. The environment can getter better, not just worse.

Today, the Thames is one of the cleanest metropolitan rivers in the world. It is no longer a foul smelling danger to health. Nor is it a ‘dead’ river, unable, because of pollution, to support any aquatic life. Now seals and dolphins are occasionally spotted outside the Houses of Parliament, and the river is home to 120 species of fish.

This all started when Bazalgette built his 82 miles of drains using more than 300 million bricks. We could do with a few more environemtal projects of this scale and ambition today.