2. Environmental Engineering Ruth F. Weiner; Robin Matthews[020-022]

Environmental Engineering 3
Figure 1-1. Human excreta disposal, from an old woodcut (source: W. Reyburn,
FZushed with Pride. McDonald, London, 1969).
the contents of chamberpots out the window (Fig. 1-1). Around 1550, King Henri II
repeatedly tried to get the Parliament of Paris to build sewers, but neither the king nor
the parliament proposed to pay for them. The famous Paris sewer system was built
under Napoleon ID,in the nineteenth century (De Camp 1963).
Stormwaterwas considered the main “drainage” problem, and it was in fact illegal
in many cities to discharge wastes into the ditches and storm sewers. Eventually, as
water supplies developed,l the storm sewers were used for both sanitary waste and
stormwater. Such “combined sewers” existed in some of our major cities until the
1980s.
‘In 1844, to hold down the quantity of wastewater discharge, the city of Boston passed an ordinance
pmhibiting the taking of baths without doctor’s orders.
4
ENVIRONMENTAL ENGINEERING
The first system for urban drainage in America was constructed in Boston around
1700. There was surprisingresistance to the construction of sewers for waste disposal.
Most American cities had cesspools or vaults, even at the end of the nineteenth century. The most economical means of waste disposal was to pump these out at regular
intervals and cart the waste to a disposal site outside the town. Engineers argued that
although sanitary sewer construction was capital intensive, sewers provided the best
means of wastewater disposal in the long run.Their argumentprevailed, and there was
a remarkable period of sewer construction between 1890 and 1900.
The h t separate seweragesystemsinAmericawere built in the 1880sin Memphis,
TN, and Pullman, IL.The Memphis system was a complete failure. It used small pipes
that were to be flushed periodically. No manholes were constructed and cleanout
became a major problem. The system was later removed and larger pipes, with
manholes, were installed (American Public Works Association 1976).
Initially, all sewers emptied into the nearest watercourse, without any treatment.
As a result, many lakes and rivers became grossly polluted and, as an 1885 Boston
Board of Health report put it, “larger territories are at once, and frequently, enveloped
in an atmosphere of stench so strong as to arouse the sleeping, terrify the weak and
nauseate and exasperate everybody.”
Wastewater treatment first consisted only of screening for removal of the large
floatables to protect sewage pumps. Screens had to be cleaned manually, and wastes
were buried or incinerated. The first mechanical screens were installed in Sacramento,
CA, in 1915, and the fist mechanical comminutor for grinding up screenings was
installed in Durham,NC. The first complete treatment systems were operational by
the turn of the century, with land spraying of the effluent being a popular method of
wastewater disposal.
Civil engineers were responsible for developing engineering solutions to these
water and wastewater problems of these facilities.There was, however, little appreciation of the broader aspects of environmentalpollution control and management until
the mid-1900s. As recently as 1950 raw sewage was dumped into surface waters in
the United States, and even streams in public parks and in U.S.cities were fouled with
untreated wastewater. The first comprehensivefederal water pollution control legislation was enacted by the U.S.Congress in 1957, and secondary sewage treatment was
not required at all before passage of the 1972 Clean Water Act. Concern about clean
water has come from the public health professions and from the study of the science
of ecology.
PUBLIC HEALTH
Life in cites during the middle ages, and through the industrial revolution, was difficult,
sad, and usually short. In 1842, the Report from the Poor Law Commissionerson an
Inquiry into the Sanitary Conditions of the Labouring Population of Great Britain
described the sanitary conditions in this manner:
Many dwellings of the poor are arranged around narrow courts having no other opening to the
main street than a narrow covered passage. In these courts there are several occupants, each
EnvironmentalEngineering 5
of whom accumulated a heap. In some cases, each of these heaps is piled up separately in the
court, with a general receptacle in the middle for drainage. In others, a plot is dug in the middle
of the court for the general use of all the occupants. In some the whole courts up to the very
doors of the houses were covered with filth.
The great rivers in urbanized areas were in effect open sewers. The River Cam, like
the Thames, was for many years grossly polluted. There is a tale of Queen Victoria
visiting Trinity College at Cambridge, and saying to the Master, as she looked over
the bridge abutment, “What are all those pieces of paper floating down the river?”
To which, with great presence of mind, he replied, “Those, ma’am, are notices that
bathing is forbidden” (Raverat 1969).
During the middle of the nineteenth century, public health measures were inadequate and often counterproductive.The germ theory of disease was not as yet fully
appreciated, and epidemics swept periodically over the major cities of the world. Some
intuitive public health measures did, however, have a positive effect. Removal of
corpses during epidemics, and appeals for cleanliness, undoubtedly helped the public
health.
The 1850s have come to be known as the “Great Sanitary Awakening.” Led by
tireless public health advocates like Sir Edwin Chadwick in England and Ludwig
Semmelweissin Austria, proper and effective measures began to evolve. John Snow’s
classic epidemiological study of the 1849 cholera epidemic in London stands as a
seminally important investigation of a public health problem. By using a map of the
area and identifying the residences of those who contracted the disease, Snow was
able to pinpoint the source of the epidemic as the water from a public pump on Broad
Street. Removal of the handle from the Broad Street pump eliminated the source of the
cholera pathogen, and the epidemic subsided.2Waterborne diseases have become one
of the major concerns of the public health. The control of such diseases by providing
safe and pleasing water to the public has been one of the dramatic successes of the
public health profession.
Today the concernsof public health encompassnot only water but all aspectsof civilized life, including food, air, toxic materials, noise, and other environmentalinsults.
The work of the environmental engineer has been made more difficult by the current
tendency to ascribe many ailments, including psychological stress, to environmental
origins, whether or not there is any evidence linking cause and effect. The environmental engineer faces the rather daunting task of elucidating such evidence relating
causes and effects that often are connectedthrough years and decades as human health
and the environment respond to environmentalpollutants.
ECOLOGY
The science of ecology defines “ecosystems”as interdependentpopulations of organisms interacting with their physical and chemical environment.The populations of the
*Interestingly,it was not until 1884that Robert Koch proved that vibrio comma was the microorganism
responsible for the cholera.