Times Have Changed

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Times Have Changed
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Many things are different now than they were only
100 years ago . . .
. . . and there are many important differences
that impact drinking water.
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Difference 1 Population has increased
substantially, yet there is no more fresh water
today than there was a million years ago.
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Difference 2 There has been a major shift from
rural to urban populations.
1900
2000
U.S. Population
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Difference 3 Water use associated with
businesses, industries, agriculture, and
individual use has increased dramatically.
Total U.S. Water Withdrawals
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Difference 4 The scale of many operations has
changed substantially.
Megafarms with widespread pesticide use
Industrial scale meat production
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Difference 5 Because of increased water
demands, natural processes that help filter
contaminants from ground water are not working as
effectively.

LOTS OF WATER
LOTS OF TIME
BIOLOGICAL Transformation
DEGRADATION
BREAKDOWN of COMPOUNDS
DILUTION
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Difference 6 The water infrastructure is
aging, with pipelines in many areas of the U.S.
dating to Victorian times!
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Difference 7 Increased population densities
have created more potential for contamination
from septic systems and wastewater.
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Difference 8 Increased quantities of goods
being transported with more frequency, across
greater distances, and through a wider variety of
means has increased potential for leaks and
spills at all stages of transportation process.
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Difference 9 New contaminants are being
introduced into the water cycle.

• Hormones and pharmaceuticals
• Synthetic chemicals
• More on the horizon?

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Difference 10 Controversy has arisen on
whether some substances used to treat water (and
for other common uses) can actually have negative
health effects long-term.
?
Chloroform molecule
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Difference 11 Many diseases have been emerging
that are resistant to standard water treatment
processes.
Cryptosporidium
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Difference 12 Extreme climactic events have
greater impact on source waters than 100 years
ago.
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Difference 13 Long-term climatic changes that
have been drying up Nevada are likely to
continue for the foreseeable future.
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Difference 14 The population is changing, with
medical advances keeping more people alive who
are particularly vulnerable to contaminants in
drinking water supplies.
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Many of the 14 differences interact and are
cumulative, and waterborne illnesses are becoming
more frequent.
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The bottom line? What worked 100 years ago isnt
working as well now, and definitely wont
continue to work indefinitely.
TIMES HAVE CHANGED