Sir Joseph William Bazalgette, CB (28 March 1819 – 15 March 1891) was an English civil engineer of the 19th century. As chief engineer of London’s Metropolitan Board of Works his major achievement was the creation in response to “The Great Stink” of 1858 of a sewer network for central London which was instrumental in relieving the city from cholera epidemics, while beginning the cleansing of the River Thames.
Joseph William Bazalgette was born at Hill Lodge, Clay Hill, Enfield, London, England, the son of Joseph William Bazalgette (1783–1849), a retired captain of the Royal Navy and Theresa Philo, née Pilton (1796–1850) and was grandson of a French Protestantimmigrant. He began his career working on railway projects, articled to noted engineer Sir John MacNeill and gaining sufficient experience (some in Ireland) in land drainage and reclamation works for him to set up his own London consulting practice in 1842. By the time he married, in 1845, Bazalgette was deeply involved in the expansion of the railway network, working so hard that he suffered a nervous breakdown two years later.
While he was recovering, London’s short-lived Metropolitan Commission of Sewers ordered that all cesspits should be closed and that house drains should connect to sewers and empty into the Thames. As a result, a cholera epidemic (1848–49) then killed 14,137 Londoners.
Bazalgette was appointed assistant surveyor to the Commission in 1849, taking over as Engineer in 1852, after his predecessor died of “harassing fatigues and anxieties.” Soon after, another cholera epidemic struck, in 1853, killing 10,738. Medical opinion at the time held that cholera was caused by foul air: a so-calledmiasma. Dr John Snow had earlier advanced a different explanation, which we now know to be correct: cholera was spread by contaminated water. His view was not generally accepted.
Championed by fellow engineer Isambard Kingdom Brunel, Bazalgette was appointed chief engineer of the Commission’s successor, the Metropolitan Board of Works, in 1856 (a post he retained until the MBW was abolished and replaced by the London County Council in 1889). In 1858, the year of the Great Stink, Parliament passed an enabling act, in spite of the colossal expense of the project, and Bazalgette’s proposals to revolutionise London’s sewerage system began to be implemented. The expectation was that enclosed sewers would eliminate the stink (‘miasma’), and that this would then reduce the incidence of cholera.
At the time, the Thames was little more than an open sewer, devoid of any fish or other wildlife, and an obvious health hazard to Londoners. Bazalgette’s solution (similar to a proposal made by painter John Martin 25 years earlier) was to construct 1,100 miles (1,800 km) of underground brick main sewers to intercept sewage outflows, and 1,100 miles (1,800 km) of street sewers, to intercept the raw sewage which up until then flowed freely through the streets and thoroughfares of London. The outflows were diverted downstream where they were dumped, untreated, into the Thames. Extensive sewage treatment facilities were built only decades later.
The scheme involved major pumping stations at Deptford (1864) and at Crossness (1865) on the Erith marshes, both on the south side of the Thames, and at Abbey Mills (in the River Lea valley, 1868) and on the Chelsea Embankment (close to Grosvenor Bridge; 1875), north of the river.
The system was opened by Edward, Prince of Wales in 1865, although the whole project was not actually completed for another ten years.
Bazalgette’s foresight may be seen in the diameter of the sewers. When planning the network he took the densest population, gave every person the most generous allowance of sewage production and came up with a diameter of pipe needed. He then said ‘Well, we’re only going to do this once and there’s always the unforeseen.’ and doubled the diameter to be used. Every Londoner should be grateful for this foresight as the then unforeseen was the tower block. If he had used his original, smaller pipe diameter the sewer would have overflowed in the 1960s. As it is they are still in use to this day.
The unintended consequence of the new sewer system was to eliminate cholera not only in places that no longer stank, but wherever water supplies ceased to be contaminated by sewage. The basic premise of this expensive project was wrong, as so often happens, but the end result was much better than expected, which is a rare occurrence. (The River Thames now contains several smaller varieties of fish, including trout; it is also safe to swim in—for those willing to brave the frigid waters and able to find a stretch without undertow.).
Bazalgette lived in St John’s Wood, north London for some years. He later moved to Morden, then in 1873, with his wife, Maria, (née Kough, 1819–1902), six sons and four daughters, to Arthur Road in Wimbledon, where he died in 1891, and was buried in the nearby churchyard at St Mary’s Church.