U5 WATTW. /C/ws
Page 7/September, 1986
wa r reuse opUtons presently avail-
able which will conserve and protect
potable water so that, in the interim,
additional research can be done to
determine the optimal, fail-safe
treatment required for direct reuse.
The first priority in reclaimed wa-
ter reuse is that it be safe, or free
from microbiological contamination.
The second priority is that it not de-
grade groundwater or surface water.
The demand for water for such
nonpotable functions as flushing
toilets and watering lawns can be
met by the use of reclaimed waste-
water. A very successful example of
such a nonpotable water reuse pro-
ject is that of St. Petersburg, Fla.
Since 1977, reclaimed water -
routinely monitored for microbiolo-
gical water quality, including
viruses has been sold for use in es-
tablished public and private lawn ir-
rigation systems. No hose bibs are
permitted, as a safety measure to
Preclude inadvertent drinking of the
The general public has yet
to accept the fact that
acute potable water short-
ages will be a reality.
wastewater treatment is to be up-
graded to permit safe water reuse
and if water conservation is to be ac-
complished, extensive educational
programs on a national level must be
Politicians and builders must ac-
cept responsibility and make some
very difficult decisions if direct reuse
of water is to be delayed long enough
to permit adequate research to be
done. Expediency must no longer be
our modus operandi.
D r % '.l!' u ., h, ,1 hh. e .,- 1 .I P 1.,./ ,..;.... > HR. .. 4
I "'l.r. Fh dr.IU I)lfpu:r!fItII *i,! H, llh .t l i,,I R-.1 .,hi:.ltl: ,. -.s.
e tSv T9 n .'r., '.r, .. i,,: .... ..
w e lrh" t pr-'n'. t.e, r r te i t"it 1I t' *
./qr v i irr gatu ti pr..;, i.
More reuse study needed
By F.M. Dwellings, Sc.D. water.
Director The project has been so successful
Epidemiology Research Center in conserving potable water that, in
State of Florida spite of the city's increased popula-
Indirect water reuse has been prac- tion, the need to replace and enlarge
ticed for centuries, but not without 50 miles of water transmission lines
problems. Through the years, vari- (which transport potable water from
ous maladies were thought to be due northern counties to the city) was de-
to water consumption, but it was not ferried from 1980 to 2010.
until 1854 that Dr. John Snow Anything that can be done to delay
clearly demonstrated the relation- the need for direct reuse provides
ship between cholera cases and the more time to develop the necessary
ingestion of contaminated water. methodologies for removing trace or-
Since then a variety of illnesses, gani and inorganics, and to estab-
including typhoid and hepatitis, lish maximal safe levels for human
have been attributed to the ingestion consumption. This is vital because
of water, particularly untreated we know so little about the long-
groundwater. Because the original term health effects of these trace ele-
source of the disease-causing agents ments.
is human biological waste, it is evi- The cost of wastewater treatment
dent that disposal of poorly treated will increase regardless of reclama-
wastewater can contaminate potable tion methods selected. In today's
water sources. economic climate, where all under-
Samo o f a takings must be cost-effective, the
The amount of freshwater avail- treatment method is decided on the
able for worldwide consumption is basis of economics. Unfortunately, in
estimated to be approximately 650 determining the cost-effectiveness of
billion gallons per day (BGD). By the wastewater treatment and disposal
year 2000, demand has been esti- alternatives, values for health and
mated to reach 1,000 BGD. The only water conservation are never fac-
source of the additional 350 BGD is tored into the equation.
reclaimed water, or treated waste- The general public has yet to ac-
water. cept the fact that acute potable wa-
It is imperative that careful consid- ter shortages will be a reality: They
eration be given now to the many take potable water for granted. If