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03/06/2001
Flushing...and Other Matters
Forgive me if I wax a bit poetic, but each year I look forward to a
particular magical morning here on Marco Island. This morning
was that morning. I walked onto the beach at 6:15 AM and there
it was, the bright, orangish full moon casting its shimmering rays
on the calm waters of the Gulf. In a crystal clear sky, the
moonset occurred just as the first light of dawn appeared on the
opposite horizon. To me one of the most awe-inspiring
spectacles Nature has to offer. Last year at this time, I wrote
about the illusion of the moon on the horizon being so much
larger than the moon overhead. I''m happy to report the illusion
still holds.
Another magical moment repeated again this year is my meeting
of a lone heron that shares my early morning observations of the
beauties of the pre-dawn scene. I''ve never seen more than this
single heron here on the Gulf shoreline; its brethren are in
abundance in the marshes and inland waterways. Of course, I
hypothesize that this is the same heron from past years and that it
recognizes me when our eyes meet. Do I fantasize too much if I
speculate that, as he stands there looking out over the water, he
ponders the meaning of life? Probably so.
I found something else this morning. Coincident with this full
moon is an especially low tide, which results in a number of
stranded tidal pools. Some three or four feet from the edge of
one of the pools was a conch. This was not surprising since
conches are popping up from underneath the sand all along the
beach. What surprised me was that this conch had left a distinct
trail that showed it had pulled itself up out of the pool and
traveled the 3 or 4 feet to its current position. Why it would do
that is a mystery to me. Shouldn''t it prefer the aqueous
environment rather than expose itself to the ubiquitous gulls, who
seem to consider a morsel of fresh conch a delectable treat?
Apropos of the marine environment here, last week''s column
dealt with water and its purification, notably in Milwaukee. I
hadn''t planned to pursue the subject of water. However, what
should I read in the February 2001 issue of Scientific American
but a special report devoted to the global aspects of freshwater
consumption and conservation...one sentence in an article by
Peter Gleick caught my attention: "Why should we raise all water
to drinkable standards and then use it to flush toilets?"
Sometimes the simplest questions are the most profound. Why
indeed should we invest all the money and effort to deliver
drinkable water to our homes and businesses when the fraction
that we actually drink is so small? It''s clear that what we should
have is a system that delivers two kinds of water - one for
drinking and one for flushing. OK, you''re right; we might want a
third source of water for bathing and laundering and dishwashing.
You''re right again; to even think about re-piping our homes and
water supply systems for just two types of water is ridiculous.
The cost would be astronomical!
So, we''re stuck with conservation. In an article by Diane
Martindale, the Big Apple is shown to be one of the leaders in the
conservation field. Back in the early 1990s, we in the New York
area were under water restrictions due to droughts and New York
City was in need of some 90 million extra gallons of water a day.
The Apple''s water, from the mountains upstate, was generally
rated as at or near the top in drinking quality in the U.S. Now,
the choice was to spend a billion dollars for a new pumping
station to pump water from the Hudson River or to mount a
major conservation effort. The Hudson River to me would not
seem as palatable a source of water as the Catskills and the choice
of conservation seems a wise alternative.
Flushing was selected as the major target and the natural tendency
of New Yorkers to look for a bargain proved effective. The city
embarked on a toilet rebate program in 1994 with a budget of
nearly $300 million to replace the conventional 5-6 gallons per
flush toilets with water-saving 1.6 gallons per flush alternatives.
The 3-year program ended with 1.33 million toilets being replaced
in over 100,000 buildings. That''s a lot of toilets! Result - a
saving of some 70-90 million gallons of water a day.
I was surprised at another conservation measure, the installation
of water meters. We''ve had water meters in our homes but
apparently New Yorkers were billed on the size of their property
rather than on the amount of water consumed. The new incentive
to save money was combined with free water-efficiency checks
and advice on installing low-flow shower heads (half the water)
and faucet aerators (one-quarter the water), as well as checks for
leaking plumbing. The result - an estimated additional 11 million
gallons saved a day.
Aside from these low technology approaches, New York has
instituted computerized sonar technology to detect leaks in its
over 6,000 miles of water mains. Leaks in water mains in some
modern systems can lead to losses as much as 20-30 percent of
the water input. According to Gleick, enough water leaks out of
the Mexico City water supply to meet the demands of a city the
size of Rome!
But those of us living in cities and towns are not the major water
consumers. According to an article by Sandra Postel, two thirds
of water use worldwide is attributable to irrigation. Indeed, some
40 percent of the world''s food supply is grown employing
irrigation. Already, in many places, the competition between
urban dwellers'' demands for water and the farmers'' reliance on
water from the same sources makes for a future of uncertainty for
both. Again, conservation must play a key role. Most irrigation
follows the 6,000 year old tradition of simply diverting water
from a river to ditches between the rows of crops. This results in
most of the water evaporating or soaking into the ground without
reaching the plants. Drip irrigation that delivers the water to the
plants drop by drop at just the right place not only saves water
but also may increase crop yields because of more ideal moisture
conditions.
Sprinklers also deliver water to the plants where it''s needed.
However, you don''t want to use the kind of sprinkler in evidence
on the typical suburban lawn. These shoot the water high into the
air and much of it evaporates into the air. A well-designed
irrigational sprinkler squirts a lower, less forceful spray just where
needed.
Sometimes the factors affecting water consumption are less
obvious. For example, replacing some of the steel with aluminum
in your automobile saves water. Why? Modern steel-making
technology requires about 6 tons of water. If this sounds like a
lot, consider that pre-World War II steel-making required from
60 to 100 tons of water for each ton of steel! This saving of
water in today''s technology is very impressive but making a ton
of aluminum only takes 1.5 tons of water. Another example is
today''s work-at-home telecommuting, which saves the hundreds
of gallons of water used in making, delivering and marketing a
gallon of gasoline.
Finally, returning to flushing, the upgrading of wastewater to
standards allowing its recycling for subsequent uses is a routine
process in countries such as Israel and Namibia in Africa. In
Israel, this recycled wastewater is used to irrigate nonfood crops
while in Namibia, wastewater has been used to add to the
drinking water supply - up to 30 percent in severe drought years.
According to Gleick, Californians have been utilizing well over a
hundred billion gallons of recycled water a year for watering golf
courses, landscapes, crops and recharging underground aquifers.
And, what else? Flushing toilets.
Allen F. Bortrum
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