Bazalgette was born at Hill Lodge,
Clay Hill,
Enfield, the son of Joseph William Bazalgette (1783–1849), a retired
Royal Navy captain, and Theresa Philo
née Pilton (1796–1850). His grandfather, Louis Bazalgette, a tailor and financier, was an economic migrant from
Ispagnac in Lozère, France, who became principal tailor to the Prince of Wales, the future
George IV, and subsequently became wealthy. In 1827, when Joseph was eight years old, the family moved into a newly built house in
Hamilton Terrace,
St John's Wood, London. He spent his early career articled to the noted engineer
Sir John Macneill, working on railway projects, and amassed sufficient experience (partly in China and Ireland) in
land drainage and
reclamation to enable him to set up his own London consulting practice in 1842. In 1845, the house in Hamilton Terrace was sold, and Joseph married Maria Kough, from
County Kilkenny in Ireland. At the time, he was working so hard on expanding the railway network that two years later, in 1847, he suffered a nervous breakdown. In 1847, while he was recovering, London's
Metropolitan Commission of Sewers ordered that all
cesspits should be closed and that house drains should connect to sewers and empty into the Thames. A
cholera epidemic ensued, killing 14,137 Londoners in 1849. Bazalgette was appointed Assistant Surveyor to the Metropolitan 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-called "
miasma". Physician
John Snow had earlier advanced a different explanation, which is now known to be correct: cholera was spread by contaminated water, but his view was not then generally accepted. Championed by fellow engineer
Isambard Kingdom Brunel, Bazalgette was promoted Chief Engineer of the Commission's successor, the
Metropolitan Board of Works, in 1856 (a post which he retained until the MBW was abolished and replaced by
London County Council in 1889). In 1858, the year of the
Great Stink, Parliament passed an
Enabling Act, despite 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 miasma that was thought to be the cause of cholera and, as a result, eliminate cholera epidemics. ==Sewer works==