Page 437 - Environment: The Science Behind the Stories

city is growing so fast that more water is needed for its pollution of the groundwater that provides your state’s
burgeoning urban population. What policies would you drinking water supply. Recent studies have shown that
consider to restore your state’s water supply? Would you one-third of the state’s groundwater has levels of pollut-
try to take steps to increase supply, decrease demand, or ants that violate EPA standards for human health, and
both? Explain why you would choose such policies. citizens are fearful for their safety. What steps would you
6. tHINk It tHRoUgH Having solved the water deple- consider taking to safeguard the quality of your state’s
tion problem in your state, your next task is to deal with groundwater supply, and why?

Calculating ecological Footprints

One of the single greatest personal uses of water is for show- average daily shower time of 8 minutes, calculate the amounts
ering. Old-style showerheads that were standard in homes of water used and saved over the course of a year with old
and apartments built before 1992 dispense at least 5 gallons standard versus low-flow showerheads, and record your
of water per minute, but low-flow showerheads produced results in the table.
after that year dispense just 2.5 gallons per minute. Given an

Annual water use with Annual water use with Annual water savings with
standard showerheads low-flow showerheads low-flow showerheads
(gallons) (gallons) (gallons)
You
Your class
Your state
United States

1. Beginning in 2010, under its WaterSense program, the 3. Compare your answers to questions 1 and 2. Do you
EPA promoted showerheads that produce still-lower save more water by showering 8 minutes with a 2-gpm
flows of 2 gallons per minute (gpm). Some cities are showerhead or 6 minutes with a 2.5-gpm showerhead?
already requiring these, and some models today go even 4. Can you think of any factors that are not being considered
lower. How much water would you save per year by using in this scenario of water savings? Explain.
a 2-gpm showerhead instead of a 2.5-gpm showerhead?
2. How much water would you be able to save annually by
shortening your average shower time from 8 minutes to
6 minutes? Assume you use a 2.5-gpm showerhead.

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etext, and the Study Area with practice tests, videos, current graded activities, current events, videos, and reading questions
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