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The Badd Olde Days

Reprinted from Cleaner magazine

A Glimpse Into London's Early Sewers

PART III

BY MARY GAYMAN

Ring a ring of rosy
A pocket full of posies
Atchoo, atchoo -
All fall down!

This familiar nursery rhyme has a grim theme. It describes symptoms of the Great Plague of 1665 which killed over 60,000 in six months. Ring of rosy refers to the red ringed spots. A pocket full of posies described the "bouquets" of strong herbs carried to ward off "badd ayre." Sneezing often preceded death and most Londoners "fell down" from disease in the stifling heat wave in 1665.

Barefoot Boy Sweeps Street Ahead of Pedestrians, 72K file size

Housing conditions in London during the 17th and 18th Century were incredibly bad, though improved by Mediaeval standards. A huge "floating population" was largely housed as weekly tenants in furnished rooms.

Those who could not find lodging slept in ale-houses, garrets, in night cellars (latrines with cesspits), in doorways and in streets. Many simply slept in rented chairs in pubs, where they were permanent guests. Coffee houses and pubs were desirable addresses for those establishing themselves in London.

Methane (swamp) gas generated by cesspits caught fire, exploded and brought instant death to those trapped in sealed homes. Hydrogen sulfide gases overwhelmed victims as they slept, their lungs paralyzed by the gas.

It is estimated that several hundred thousand Londoners perished from typhoid, cholera, plague and pestilence before it was understood that the City was dying from its own filth.

Microscopic Image of Contaminated Water

Finally, it was up to the Sewer Commissioners to find a way to rid the city of centuries of human waste stored within its walls.

Servants, such as cooks and maids, slept in the kitchens or pantries. There were 6,000 hog pens and countless slaughterhouses in the housing areas. Bathing and fresh air were feared. Most people had only one set of clothes. How often these were washed or cleaned is not known.

The crowded conditions in London were due, in part, to social tradition, but were mostly dictated by the need to be near a place of work. The small stalls of "Costermongers" lined the streets vending every manner of goods from buttons and brick to breads and sausage from cattle slaughtered on the spot.

Traffic Jam on the London Bridge, 102K file size

By 1780 there were more than 60,000 horses trodding the streets daily. Chickens, geese, and ducks shared courtyards and alleys with goats, pigs and sheep.

The Industrial Revolution brought huge populations in to London. Factories belched out new kinds of chemical wastes into the streets and ditches used as open latrines. Sixty sewers drained directly into the Thames, from which six of the nine water suppliers drew the unfiltered drinking water for the city.

In some cases, the drains were higher than the cesspits or basements. As a result, septic wastes flowed back into buildings, saturating walls and flooding rooms.

Thames backup causes City flooding, 66K

Street overflow was channeled into open trenches, courts, alleys or any available cavern. With increasing frequency abandoned cesspits and drains collapsed under the weight of traffic and became the burial ground for horses and drivers along with carts and freight.

As the waste piles grew, experts and amateurs flocked into the hearing rooms to present a numbing array of solutions to London's plight.

Back to the future ... lessons from the past

Ironically, the solution to society's ills were written in stone, papyrus, and in traditions long abandoned.

Dozens of scholars came forward to extol the merits of waste water systems used by ancient civilizations.

Commissioners heard historians praise the 4,000 year old Minoan drainage system at Knossos, where rain-fed cisterns and stone aqueducts were tapped water sources in the hills to deliver a continuous flow through the bathrooms and latrines. Waste was carried away by terra cotta pipes joined with cement.

They were reminded that only 2,000 years before, the sewers of Athens delivered waterborne human waste materials to a collecting basin outside of the city. Flow from this basin was channeled through brick lined conduits to irrigate and fertilize orchards and fields.

The great Roman sewer or Cloaca Maxima, which still drains the Forum, was built to handle rainfall runoff and, only coincidentally, was found useful to remove human wastes when crowds were present.

The solution to pollution is ... dilution

European city authorities were also seeking solutions. Many were mandating that human wastes be discharged through interior plumbing into existing storm drains and directed to the nearest waterway. Clearly the solution was water!

The Minutes of Information on the Application of Refuse of Towns to Agriculture reported to the London commission that "in no mode can refuse be so well received, so completely preserved and so productively applied as in suspension in water."

Mr. Rammell, one of the inspectors of the Board, set forth the facts gathered on a visit to Paris. He recommended that "the soil-pan or water-closet principle and the tubular mode of drainage be introduced into English towns."

Rammell argued that "the substitution of water closets for cesspools (while involving the loss of profits from manure) would nevertheless be economical since the annual cost of a cesspool including interest, depreciation repairs, and expenses for emptying considerably exceeds the annual cost of a water closet with connection to the tubular system constructed in the street."

Local Health Boards were directed to "oversee the abolition of all cesspools and the prevention of future formation, by the complete drainage of every house in town."

In some places, portable cesspits were used until new main sewer lines were constructed.

Before prioritizing of the water closet, no standard form of drainage was enforced. A haphazard network of shallow flat bottomed channels or covered open trenches with some kind of support were meant to carry the cesspit flow to the main drains in the center of the streets.

Going with the flow ... combining old and new

In London, the Commissioners discussed separate systems for human wastes and storm water because the engineering of two systems were too complex to engineer quickly and too costly to complete. After extended hearings, a combined system was deemed the quickest and least costly to move wastes away from the center of London.

Easy maintenance after installation was a primary consideration. Tests showed that a velocity of 2 feet per second would move solids along in a sanitary sewer, but that a velocity of 3 feet per second was needed to prevent the disposition of sand, gravel and debris washed into the system by rainstorms.

Studies showed the lower part of a "V" channel form could carry sanitary waste flow along well while the upper portion could provide sufficient capacity to transport storm water from the streets. This discovery led to evolution of the egg shape, which provided a smooth surface proven most effective in transporting flows rapidly. Where there was not sufficient slope, lifts and pumps were planned to helped prevent settling out of solids.

Two early sewer designs, 48K

Designing a system which would carry both sewage and storm water gave rise to vigorous, lengthy and detailed discussions among Commission members.

The commission concluded that smooth interior clay pipe was well suited for smaller lines but determined egg shape was better to accommodate combined flows in the main collector.

Finally, egg or oval mains were selected for combined storm use and round clay pipe was approved for sewage. A decision was, at last, entered into the record by the Chairman.

"For intermittent purposes, where the house sewage occupies only a small portion of the area, but the sewer is liable to be filled with storm water, the egg shape is undoubted to be best."

"In proportion as the flow can he equalized and adjusted, and the principles of drainage reduced by practical science and the approximation of constants, to the same extent the egg shape must yield to the circular, as the best form of sewer, without reference to size.''

Five sewer pipe designs, 42K

Over time, the "self cleaning" characteristics of the egg shaped pipe proved to be as effective in self cleaning as the engineers had projected.

As for clay pipe, the laurel wreath goes to the Minoan-Greco-Roman group in recognition for pioneering a truly environmentally correct design.


Republished courtesy of Cleaner magazine (Cole Publishing Inc., POB
220, Three Lakes WI 54562 USA, tel. 800-257-7222 or 715-546-3346) and
author Mary Gayman.

== Caption Text, for those without graphical browsers:

1. London's drinking water, drawn unfiltered from the polluted Thames River, was home to many disease-causing organisms and other nasty critters.

2. Mid 1800s traffic jam on the London Bridge -- 8 million horses crossed the span every year.

x. 1850 London News illustration showing routine city flooding when the Thames "backed up."

x. Early sewer designs. Best "capacity" for combined use was the oval shape (right) and best hydraulic combination was the egg shape (left). (Illustrations from WRC library)

x. More early sewer designs:

a) A "combined conduit with V bottom led to better hydraulics at the bottom for "cleaning."

b) A covered "horseshoe" shape laid close to the surface and with no bottom allowed sewage to seep into the ground enroute.

c) The most common structure for draining cesspits.

d) A common form of construction of brick barreled house drains.

e) Flat brick house drains were generally put in without mortar at the bottom, so that much of the sewer refuse permeates the site of the house while the deposits ultimately choked up the drain.


Republished courtesy of Cleaner Magazine, a publication of Cole Publishing Inc., POB 220, Three Lakes WI 54562, tel. 800-257-7222 or 715-546-3346, and author Mary Gayman.

Return to the Sewer History area of the SwopNet Engineering Databank. There you will find the Thomas Crapper photo page and the Septic Tank resources page.

Joseph Bazalgette was the Father of London Sewers. You can read his story here.