Sir Joseph Bazalgete

Sir Joseph William Bazalgette (28 March 1819 – 15 March 1891) was a groundbreaking English civil engineer renowned for transforming London’s sewerage system. As Chief Engineer of the Metropolitan Board of Works, Bazalgette tackled the city’s severe sanitation issues, especially following the Great Stink of 1858. His work was instrumental in ending cholera epidemics and improving the River Thames’s water quality.

Bazalgette began his career as an apprentice to the respected Engineer Sir John Macneill, working on railway projects. His extensive experience in land drainage and reclamation, gained from work in China and Ireland, enabled him to start his consulting practice in London in 1842. He married Maria Kough from County Kilkenny, Ireland, in 1845, but the pressures of his work led to a nervous breakdown in 1847.

While Bazalgette was recovering, London faced a severe cholera outbreak in 1849 that killed 14,137 people. The city’s outdated sewerage system exacerbated the crisis. At that time, the prevailing theory was that cholera was caused by foul air, or “miasma,” while the real cause—contaminated water—was not yet widely accepted.

In 1849, Bazalgette was appointed Assistant Surveyor to the Metropolitan Commission of Sewers, becoming Engineer in 1852 after his predecessor’s death. The Metropolitan Board of Works replaced the commission in 1856, and with support from engineer Isambard Kingdom Brunel, Bazalgette was promoted to Chief Engineer. The Great Stink of 1858 underscored the urgent need for reform, leading Parliament to approve Bazalgette’s ambitious plans despite the high cost.

Bazalgette’s solution involved constructing 82 miles (132 km) of enclosed underground brick sewers and 1,100 miles (1,800 km) of street sewers to redirect raw sewage away from the Thames, which had become an open sewer. Major pumping stations were built at Deptford and Crossness on the south and Abbey Mills and Chelsea Embankment on the north. Sewage was diverted to outfall systems, where it was dumped into the Thames at high tide. The system was inaugurated by Edward, Prince of Wales, in 1865, although full completion came in 1875.

Although Bazalgette’s design was based on the incorrect belief that cholera was caused by miasma, the new system had a profound effect: it effectively removed the bacteria responsible for cholera from London’s water supply, leading to a sharp decline in cholera cases and reducing other diseases like typhus and typhoid. The success of the sewer system eventually led to the development of extensive sewage treatment facilities in the early 20th century.

Bazalgette’s dedication was evident in his hands-on approach to the project. He personally reviewed every sewer connection, leaving detailed notes on thousands of linen plans. His tireless work, however, took a toll on his health.

Today, Sir Joseph Bazalgette is celebrated for his pivotal role in improving urban sanitation and public health. His sewer system laid the groundwork for modern infrastructure and significantly enhanced London’s development as a healthier city.