The history of decontaminating our water
The Chief Medical Officer for England, Chris Whitty, recently wrote that “one of the greatest public health triumphs of the last 200 years was separating human faeces from water” noting that “only vaccination matches it as a public health intervention for preventing infectious diseases”. However, despite the now universal acceptance that effective sewage treatment is crucial for good public health, there was an initial reluctance to develop proper sanitation systems in the 1800s when it was first proposed.
One of the first catalysts for the development of a drainage system was an enquiry into sanitation led by Sir Edward Chadwick following a serious outbreak of Typhus in 1838. In fact, the first ever appointed public health official (now known as a Director of Public Health), Dr William Henry Duncan James, was just one of many medical practitioners who contributed to Chadwick’s report. Dr Duncan’s contribution displayed the link between poor sanitation and the spread of disease, supporting calls for Government intervention and improvement.
Among other progressive steps, Chadwick’s report led to the Public Health Act 1848 which sought to require every town to supply water to all houses and was the first instance of the British Government taking responsibility for the health of its citizens.
This, combined with ‘The Great Stink of London’ in 1858, which saw hot summer temperatures cause an intolerable stench from the then open sewer system, The River Thames, forced Parliament to realise the urgency of developing a modern sewage system in London. The civil engineer Joseph Bazalgette was tasked with completing the work and was elected as Chief Engineer of the Metropolitan Board of Works. Aside from minor adaptions, the infrastructure remains the basis for today’s sewerage design.
This was not, however, the first sewage system designed in the UK. The development of a sewage system in urbanised areas first began in Liverpool in 1848, when James Newland led a sewer construction programme which, upon completion in 1869, saw over 300 miles of sewers built and more than doubled life expectancy in the city, which had been just 19 years of age.
Sewage has demonstrable links to the transmission of infectious diseases, as exemplified by John Snow’s work in 1854 linking the cholera epidemic to contaminated drinking water. In the present day, testing and sequencing of sewage has been utilised to tackle Covid-19 outbreaks in the interest of variant detection, with Directors of Public Health recognising wastewater sampling analysis as an effective additional measure for localised outbreak control.
Wastewater treatment is an important factor in effective sewage management and has recently gained increased attention. In 2022, the Environment Audit Committee highlighted in a statement that “only 14% of English rivers meet good ecological status with pollution from agriculture, sewage, roads and single-use plastics”. The report also warned that “not a single river in England had received a clean bill of health for chemical contamination”.
The dumping of sewage and waste water into the sea can be extremely detrimental to public health. ADPH President Jim McManus commented on the issue in August 2022 and again this year, recognising its harmful effect on the economy, ecosystems, and public health. Stomach, chest and ear-infections alongside e-coli and salmonella can all be contracted through contact with dirty water. The comments made by Jim have added pressure on UK water regulators to update their systems to be suitable for the 21st Century. While water sampling can help identify dangerous areas, as Prof McManus noted during an interview with BBC Radio 5 Live, sampling of water would not be necessary if the dumping of raw sewage was prohibited.
As a key component in controlling the spread of preventable, infectious diseases, sewerage systems are a vital public health measure and have been saving lives for over 150 years and so it is essential that systems are adapted and modernised to keep the population free from disease.