"Londoners who can remember the state of London and of the Thames about thirty-five years ago, before those vast undertakings of the Metropolitan Board of Works, the system of main drainage and the magnificent Thames Embankment, which have contributed so much to sanitary improvement and to the convenience and stateliness of this immense city, will regret the death of the able official chief engineer, Sir Joseph Bazalgette."

Illustrated London News, March 1891.

Thus read the obituary of perhaps one of the greatest engineers of the 19th century. Sir Joseph William Bazalgette (1819-1891) was responsible for public health works on an unprecedented scale in the largest city the world had ever known - London. As an engineer he was well known and respected by such contemporaries as Sir William Cubitt, George Parker Bidder, Isambard Kingdom Brunel, Robert Stephenson and Thomas Hawksley. Yet he is now largely forgotten, and despite the key rôle he played in the development of the City of London, he has no published biography. The wide implications of his work, and their bearing on the development of his field, are still relevant today.

Early Life:

Joseph William Bazalgette was the fourth child, and only son, of Joseph and Theresa Philo Bazalgette. His father had been involved in the Napoleonic wars, and had left the Navy with the rank of Commander and a distinguished record. Having been privately educated, by the age of nineteen, Joseph was already studying to become a civil engineer. In February 1845, he was married to Miss Maria Keogh at St. Margaret's Westminster, and in October they moved into a newly built house. Six years later they had moved to Morden in Surrey and had started a young family; eventually Joseph and Maria had ten children. In 1873 Joseph built a house called "St. Mary's" opposite a parish church (of the same name) in Wimbledon, where he eventually died in 1891. He was buried in the family vault in St. Mary's churchyard.

Bazalgette's early engineering career prepared him for his later work on sanitation. In 1836, Bazalgette became an "Articled Pupil" of John McNeil, an Irish civil engineer. During McNeil's land drainage works in Londonderry, Bazalgette was Resident Engineer, and the works formed the topic of his first paper to the Institution of Civil Engineers, of which he was elected a Graduate and later a Member. At the age of 23 he set up his own private practice as a consulting engineer, but during 1847-8 (the period of "railway mania"), the pressure of work caused him to have a severe breakdown in health. He left London to recuperate, and later wrote that he had almost killed himself.

Works with The Metropolitan Commission of Sewers:

Sanitary reform characterised the middle years of the 19th century, and new legislation provided the funds and administrative structure needed for massive engineering schemes in public health works. The consequences of inadequate drainage became serious as London expanded during the early Victorian period. The Thames was filled with human and animal excrement, industrial waste, and the rotting corpses of cats, dogs, and fowl. As Bazalgette later reflected, small local attempts to deal with the problems, "produced results as multifarious as they were discordant". By the 1840s, government intervention had become inevitable. In 1847, a Royal Commission was set up to deal with house, street and land drainage in London. The members of this proposed the amalgamation of the seven existing drainage districts, and brought about the first Metropolitan Commission of Sewers in an Act of 1848. This Act gave the Commissioners power over the drainage of certain areas within a 12 mile radius of London (measured from St. Paul's Cathedral) but, significantly, not over the city itself. Each Commission consisted of twelve men who held office for two years. Between 1848 and 1855, there were six such Royal Commissions.

In 1849, Bazalgette returned to London after recovering from his illness. On the 16th of August he was appointed Assistant Surveyor to the second Commission. Thus began his engineering career in local government. The Metropolitan Commission had already established a plan of what was to be undertaken as regards drainage of the city. There were to be separate components for north and south of the Thames, and interceptor sewers running east-west with remote outfalls to the east of London. In 1852, Bazalgette was appointed engineer to the Commission, and until 1855 was very active in the Metropolitan Commission of Sewers, dealing with such things as how the construction of the Underground railway would affect sewerage plans. However, all of this was a prelude to his real achievements on the Metropolitan Board of Works, formed in 1855.

Works with The Metropolitan Board of Works:

The Metropolitan Board of Works was created under the Metropolis Management Act of 1855. It was responsible for the built-up environment within the capital's area of 117 square miles. The Board comprised 45 members, but had neither offices nor technical staff. As a result, they decided to give Bazalgette charge of the main sewers and other works in a temporary capacity until the Board could appoint an elected engineer. Out of nine applicants, Bazalgette was eventually elected as engineer, and he appointed three assistant engineers to work under himself.

It is now known that many diseases such as typhoid, cholera, numerous diarrhoeal diseases and dysenteries, are water-borne, being spread via the fæcal-oral transmission route. Other intestinal parasites are also transmitted in a similar fashion. Until the mid-19th century, however, this was speculation. The transmission route for cholera was proven in 1854 by Dr. John Snow when he showed that water drawn downstream of sewage discharges was contaminated with the bacteria. This was the first time that anyone had conclusively proved that diseases could be spread by wastewater, and the discovery led to numerous projects to improve sanitation in cities throughout England. This, coupled with the ever-deteriorating state of the Thames, meant that public health reform was long overdue. The Times editorials from this time illustrated both public opinion and resistance to the change, and the new ideas. The editorial for the 1st of August 1854 emphasised resistance to improvements in public health:

"...we prefer to take our chance of cholera and the rest than be bullied into health. ...There is nothing a man so much hates as being cleaned against his will, or having his floors swept, his walls whitewashed, his pet dung heaps cleared away... It is a positive fact that many have died of a good washing."
However, the tone had changed somewhat two days later, when the editorial said that:
"Cleanliness is supremely beneficial, but it involves some trouble and, what is worse, some expense; but in the long run commonsense prevails, and everyone testifies to the advantages of the result."

In January 1856, Bazalgette described to the Board the problems they had inherited:

"...the whole of the sewage passed down sewers from the high ground at right angles to the Thames into the low grounds adjoining the Thames, where at high water it was pent up in the sewers, forming great elongated cesspools of stagnant sewage, and then when the tide went down and opened the outlets the sewage was poured into the river at low water at a time when there was very little water in the river."
He proposed a scheme of intercepting sewers (fundamentally that of the last Metropolitan Commission) running parallel to the river and terminating at Barking on the north side (with three sewers) and at Erith on the south (with two). These would intercept the flows from existing sewers, but instead of allowing them to discharge directly into the Thames in London, their flows would be conveyed to the outfalls mentioned, and discharged at points where pestilent conditions were less likely to arise. Overall, the length of these sewers was to be 161km. At first, the plans were rejected on the basis that they discharged the sewage within the metropolitan boundaries, and were therefore in breach of the Metropolis Local Management Act. The Board replied that they had considered siting the outfalls below Gravesend, but that this would cost between £1 million and £2 million extra, with no benefit to ratepayers, and that this plan would only be considered if the government met the additional cost.

After being held up by innumerable bureaucratic delays, an Act of Parliament in August 1858 essentially gave the Board a free hand in drainage matters. It was no coincidence that 1858 was known as the "Year of the Great Stink" as a result of a particularly hot summer accelerating the decay of the already-fetid Thames. The smell was so strong that sheets soaked in disinfectant were hung at the windows of the House of Commons in an ineffective effort to dispel the stench, and one London newspaper commented that the smell, "created as much anxiety in the public mind as did the revolt in India last year". Certainly, bills being debated in the Commons were resolved by those present much more quickly than any previously! Such an incident had been warned of in 1855 when the scientist Michael Faraday wrote a letter to The Times detailing an unpleasant encounter of his own with the Thames, and suggesting that something should be done. Bazalgette was instructed by Benjamin Disraeli (the Prime Minister) to deal with the "stink" before Londoners were asphyxiated and the problem became political. Bazalgette immediately implemented his scheme of intercepting sewers. Using over 318,000,000 bricks, Bazalgette laid the intercepting sewers at a fall of 2 feet per mile, designing them to cater for twice the average volume of sewage to allow for daily variation in flow, and providing for rainfall and heavy storms. He constructed outfall reservoirs to retain up to six hours' worth of sewage flow, and the main pumping engine at Crossness moved 5½ tons of sewage with each stroke. The sewage was left untreated, and it was then discharged into the ebb tide. Experimentation has now shown that, in limiting the discharge to these intermittent tidal conditions, the sewage was transported as far out to sea as if it been discharged continuously a further 19km closer to the sea (as in the scheme for which the government had campaigned).

On Tuesday 4 April 1865, six years after their beginning, the drainage works were ceremonially opened, although work on the north side of the river had been delayed due to the difficulties of accommodating low level sewers in the Victoria Embankment (which had also been constructed by Joseph Bazalgette). The system continued to operate unchanged for about twenty years until the Board decided to make minor modifications (introducing chemical treatment of the sewage in the outfall reservoirs) due to the growth of the city.

Further Works:

The Board was also responsible for the construction of the Thames Embankment, consisting of the Victoria, Albert and Chelsea Embankments. Bazalgette took charge of the design and supervision of this project, and the Thames Embankment today carries his monument. He later said, "I get most credit for the Thames Embankment, but it wasn't anything like such a job as the drainage". While a less arduous task, the Embankment was no less valuable: it extended a distance of 3½ miles along the river, allowing about 52 acres of land to be reclaimed. Work began in 1864 on the Victoria Embankment, and by 1874, all three sections were completed. The Victoria Embankment was by far the most complex and impressive of these. It was built within cast iron cofferdams, and founded on 12'6" of concrete with a brick wall on top. The massive scale of the work can best be illustrated by the quantities of materials used for the Victoria Embankment alone:

	Granite:	650,000 cubic feet
	Brickwork:	80,000 cubic yards
	Concrete:	140,000 cubic yards
	Timber:	500,000 cubic feet
	Iron caissons:	2000 tons
	Earth filling:	1,000,000 cubic yards
	Excavation:	144,00 cubic yards
	York Paving:	125,000 square feet
	Broken granite:	50,000 superficial yards

Bazalgette and the Metropolitan Board of Works were not only responsible for sanitation, and Bazalgette also engineered flood prevention measures. His system protected wharves from flooding through a system of movable tide boards, over a total of 40 miles of river frontage. The Board also acquired, renovated, and freed from tolls the Thames' bridges. They constructed the Blackwall tunnel under the Thames, and constructed a steam ferry for crossing the river. Street improvements also fell under Bazalgette's remit. Over 3000 new streets and thoroughfares were constructed between 1860 and 1889, when the Board was disbanded. Bazalgette was also involved in the first significant step taken by a public authority in connection with electric street lighting, when an experimental French system was installed to illuminate the Victoria embankment. Throughout his career, Bazalgette was also involved in much consultancy work for other public works in towns and cities both at home and abroad. He was responsible for the Maidstone bridge over the river Medway, completed in 1879. He also regularly judged competitions for the best designed drains and sewers. In 1889, the same year that the Metropolitan Board of Works was dissolved, Sir Joseph Bazalgette retired at the age of 70 years. He died in 1891, and in 1901, his memorial on the Victoria Embankment was unveiled.

While his work on the Thames Embankment is by far his most visible achievement, and which now carries his monument, it was Bazalgette's sewerage scheme that was his greatest feat of engineering. Taken in its own period, with the knowledge then available, Bazalgette's drainage scheme for the London area was an outstanding example of Victorian enterprise. He used new and innovative techniques to sanitise the Thames, efficiently removing waste and sewage downstream to where it could be safely (in Victorian terms) be disposed of. Whilst his system of sewers would certainly not stand up to the safety and health criteria of the modern world (the raw sewage was left untreated), at the time of construction it was immensely superior to the previous systems in use: overflowing cesspits and overused, unsanitary drains, disgorging themselves when the river was at its lowest. However, rather than discard these obsolete installations, Bazalgette improved and expanded them, and fed them off into his new intercepting sewers which then emptied their pestilent load where it would be swept out to sea, without going to the additional expense of tunneling further than was necessary. He anticipated the growth of the city in his estimations. He did not claim the originality of the work for himself, stating that it would be difficult to determine from the many contributors who were the authors of the various proposals. However, it was certainly due to his pragmatic ability to transform ideas and theory into a feasible and practicable scheme, and his efficient management of the work, that it became the system still in use today.

Bazalgette's theories, however, went against those prevalent at the time. The popular idea was that sewage could be used for profit by selling it to farmers for land fertilisation. The idea was that not only would this dispose of sewage effectively, it would also profit towns and cities with much sewage to sell, and might ultimately reduce hunger through increased farm produce. In 1865, a Royal Commission reported that, "The right way to dispose of town sewage is to apply it directly to the land, and it is by such application that the pollution of rivers can be avoided." Similarly, the French author Victor Hugo in his book Les Misérables of 1868 said, "All the human and animal manure which the world loses... by the discharge of sewage to rivers... if returned to the land instead of being thrown into the sea, would suffice to nourish the world." In the 17th Century, London still exported urine in great quantities to Whitby for use in the alum industry. However, these methods were unsafe and unsanitary, and Bazalgette's sewers disposed of the waste much more cleanly (despite the lack of treatment) with the only profits being the health of Londoners.

Bazalgette's sewage system was the basis of, and comprises much of London's present system. However, the entire sewage flow of the metropolis was discharged into a stretch of river only 3 miles long between Beckton (Barking) and Crossness. Even later, when the sewage was treated prior to discharge, decaying wastes caused severe oxygen depletion in this region. Had the discharge been nearer the sea, much of the pollution of the 1950s could have been avoided. Nevertheless, as has already been stated, the works of Bazalgette were unprecedented both in their approach to the problem and in their scale. Bazalgette's system was used as the basis for other sewage systems, and his ideas were replicated in towns and cities across the country. Bazalgette's sewers operated on the theory that if waste was sufficiently diluted, it could be more safely disposed of. He recognised that water itself could be a medium for waste extraction. While we have since discovered that, "it is an illusion that the solution to pollution is dilution", Bazalgette's ideas were built on by other engineers, and paved the way for the more modern practices of waste disposal we see today. The main downfall of Bazalgette's sewage system, as has already been hinted at, was that the waste was left raw and untreated when discharged. However, it must be remembered that sewage treatment was unheard of during this period, and the new sewers were the best sanitation system London had ever had. Nevertheless, about twenty years after its completion, the system was upgraded to treat the sewage it handled. Sewerage design has now changed. Bazalgette designed what are known as 'combined' sewers, carrying both foul sewage and stormwater. At the time, this was fine because the relatively innocuous stormwater purged the sewers at intervals and the sewage received no treatment. Nowadays sewers are usually designed as 'separate' systems, consisting of discrete sewers for foul sewage and stormwater. The stormwater receives little or no treatment, and treatment facilities would be overloaded following storms by flows from combined systems. Bazalgette therefore produced good designs for his time, but these have been developed and superseded by his successors. The techniques for providing clean water and a system of sewage disposal pioneered in London by Sir Joseph Bazalgette set a model for the rest of Britain - and today the developing world - to follow.


Sources:

  • Barty-King, Hugh Water: The Book. (Quiller Press)
  • Chrimes, Mike Civil Engineering 1839-1889. (Alan Sutton/Thomas Telford)
  • Doxat, John The Living Thames: The Restoration of a Great Tidal River. (Hutchinson Benham, London)
  • Smith, Denis (Ph.D., M.Sc., D.I.C., C.Eng. [Member]) Sir Joseph William Bazalgette (1819-1891), Engineer to the Metropolitan Board of Works. (Paper presented at the Science Museum, London, on 25 March 1987)
  • Wood, Leslie B. The Restoration of the tidal Thames. (Adama Hilger Ltd, Bristol)