Environmental Engineering Reference
In-Depth Information
Drinking, or
potable
, water can be defined as the water delivered to the
consumer that can be safely used for drinking, cooking, washing, and other
household applications. In the past, drinking water suitable for use (i.e., safe)
was simply certified as safe by a professional engineer specialized in the
field, but times have changed. This practice is no longer accepted. Why?
Because public health aspects have reached such a high level of importance
and complexity that local licensed health officials usually must be designated
as those with the authority and jurisdiction in the community to review,
inspect, sample, monitor, and evaluate the water supplied to a community on
a continuing basis. This professional scrutiny is driven by updated drinking
water standards, of course. When you factor in the importance of providing
a safe, palatable product to the public, the fact that public health control is
required to help ensure a continuous supply of safe drinking water makes
real sense.
On many occasions, drinking water practitioners have attempted to explain
to interested parties the complexities of providing safe drinking water to
their household taps. Of course, we know the process is complex, but we
still continue to be surprised when listeners are astonished at the complex
procedures and processes involved. It becomes readily apparent that a com-
monly held view is that the provision of drinking water to the consumer tap
involves nothing more than going down to the local river or stream, install-
ing a suction pipe into the watercourse, and pumping the water out and into
a distribution network that somehow delivers clean, safe drinking water to
the household tap.
We then explain that, yes, water often is taken from a local river or stream,
and that it does eventually find its way to the household tap. However (isn't
there always a “however” in any explanation?), we explain that the water
drawn from any local surface water supply must pass through certain pro-
cesses to ensure wholesomeness and safety. Aside from the physical treat-
ment processes to screen, filter, and disinfect the water, these processes
include continually inspecting, sampling, monitoring, and evaluating the
water supply.
Drinking water practitioners learn the ins and outs of drinking water pri-
marily from experience. The main lesson learned is that supplying drink-
ing water to the household tap is a complex and demanding process; for
example, it is obvious that water analysis is required but it alone is not suf-
ficient to maintain quality. It must be combined with the periodic review and
acceptance of the facilities involved.
What does this mean? Simply stated, acceptance or approval requires eval-
uation, maintenance, and proper protection of the water source; qualified
waterworks personnel; adequate monitoring procedures by water suppliers;
and evaluation of the quality and performance of laboratory work (DeZuane,
1997). Thus, when we attempt to define drinking water, we must define it
in all-encompassing terms. Drinking or potable water is a product from an
approved source that falls within certain physical, chemical, bacteriological,
