Environmental Engineering Reference
In-Depth Information
watercourse to drink would not ingest too much of the water (as little of it as
possible, in fact) if it was salty. Our intrepid (but thirsty) ancestor would prob-
ably move on to find another water source, one a bit more palatable.
Determining water's fitness to drink was a matter of sight, smell, and a quick
taste. If the relevant criteria were met, the water was used. Our early kinfolk
were likely to have gulped down water that looked perfectly clear, smelled
all right, and did not taste all that bad. Later that day, though, the water could
have made them become sick, very sick—sickened by waterborne pathogens
that were residents of that perfectly clear, not too bad tasting water ingested
a few hours earlier. Of course, early humans would not have had the foggiest
idea what caused the sickness, but they would have become very sick, indeed.
Let's take a look at more recent times, at another scenario that helps illus-
trate the point that we are making here (Spellman, 1996, p. 65):
An excursion to the local stream can be a relaxing and enjoyable under-
taking. On the other hand, when you arrive at the local stream, spread
your blanket on the stream bank, and then look out upon the stream's
flowing mass only to discover a parade of waste and discarded rubble
bobbing along the stream's course and cluttering the adjacent shoreline
and downstream areas, any feeling of relaxation or enjoyment is quickly
extinguished. Further, the sickening sensation the observer feels is not
lessened but made worse as he gains closer scrutiny of the putrid flow.
He easily recognizes the rainbow-colored shimmer of an oil slick, inter-
rupted here and there by dead fish and floating refuse, and the slimy fun-
gal growth that prevails. At the same time, the observer's sense of smell
is alerted to the noxious conditions. Along with the fouled water and the
stench of rot-filled air, the observer notices the ultimate insult and trag-
edy: The signs warn: “DANGER—NO SWIMMING or FISHING.” The
observer soon realizes that the stream before him is not a stream at all;
it is little more than an unsightly drainage ditch. The observer has dis-
covered what ecologists have known and warned about for years. That
is, contrary to popular belief, rivers and streams do not have an infinite
capacity for pollution.
This relatively recent scenario makes an important point for us: The quali-
ties of water that directly affect our senses are the first to disturb us. This
certainly was the case with ancient humans, before the discovery of what
causes disease and waterborne disease in particular.
Even before the mid-1850s, when Dr. John Snow, in London, made the con-
nection between water and disease (i.e., the waterborne disease cholera),
rumblings could be heard in that city about the terribly polluted state of
the Thames River. Dr. Snow's discovery of the connection between cholera
and drinking water obtained from the Broad Street pump that was ingested
by those who became ill or died lit the fire of reform, and revulsion set in
motion steps to clean up the water supply. Since Snow's discovery, many
subsequent actions taken to clean up a particular water supply resulted from
incidents related to public disgust with the sorry state of the watercourse.