Page 418 - Environment: The Science Behind the Stories

(a) 16th-century chapel in Mexico City (b) Sinkhole in Florida
Figure 15.13 When too much groundwater is withdrawn, the land may weaken and subside. This can
cause buildings to lean, as seen in Mexico City (a). Large areas of land may sometimes collapse suddenly in
sinkholes, as seen here in Florida (b).

1990s overpumping had drawn the Ogallala Aquifer down by Groundwater supplies our bottled water
85 trillion gallons, a volume equal to half the annual flow of
the Mississippi River. These days, our groundwater is being withdrawn for a new
When groundwater is overpumped in coastal areas, purpose: to be packaged in plastic bottles and sold on super-
salt water from the ocean can intrude into aquifers, making market shelves. Bottled water is booming business. The aver-
water undrinkable. This has occurred in Florida, the Mid- age American drinks 29 gallons of bottled water a year, and
dle East, and other locations. Moreover, as aquifers lose in 2012 sales topped $15 billion in the United States and $65
water, they can become less capable of supporting overly- billion worldwide. Americans now drink more bottled water
ing strata, and the land surface above may subside. For this than beer or milk and pay more per gallon for it than for
reason, cities from Venice to Bangkok to Beijing are slowly gasoline.
sinking. Mexico City’s downtown has sunk over 10 m (33 Most people who buy bottled water do so for portability
ft) since the time of Spanish arrival; streets are buckled, and convenience, or because they believe it will taste better or
old buildings lean at angles, and underground pipes break be safer and healthier than tap water. However, in blind taste
so often that 30% of the system’s water is lost to leaks tests people think tap water tastes just as good, and chemical
(Figure 15.13a). analyses show that bottled water is no safer or healthier than tap
Sometimes land subsides suddenly, creating sinkholes, water (see The Science behind The STory, pp. 418–419). Much of
areas where the ground gives way with little warning, occa- it is municipal tap water that corporations have simply purified,
sionally swallowing homes and businesses (Figure 15.13b). packaged, and marked up in price to sell. In fact, when you buy a
Once the ground subsides, soil and rock becomes compacted, bottle of water, you have no idea where it came from or what its
losing the porosity that enabled it to hold water. Recharging a quality really is. The U.S. government strictly regulates the tap
depleted aquifer thereafter becomes more difficult. Estimates water that municipal governments provide us, but it requires lit-
suggest that compacted aquifers under California’s Central tle reporting from the corporations that sell us water in bottles at
Valley have lost storage capacity equal to that of 40% of the prices up to 1900 times more expensive than water from the tap.
state’s surface reservoirs. Bottled water also exerts substantial ecological impact CHAPTER 15 • Fr E shwat E r s yst E m s and rE sour CE s
Falling water tables also do vast ecological harm. because it is heavily packaged and because we transport it long
Permanent wetlands exist where water tables reach the sur- distances using fossil fuels. A 2009 study calculated the energy
face, so when water tables drop, wetland ecosystems dry up. costs of bottled water to be 1000–2000 times greater than the
In Jordan, the Azraq Oasis covered 7500 ha (18,500 acres) energy costs of tap water. Most energy was used in manufac-
and enabled hundreds of thousands of migratory birds and turing the bottle and transporting the product. Other studies
other animals to find water in the desert. As a result of exces- indicate that producing one liter of bottled water requires the
sive groundwater pumping by farmers and the nearby city of input of a quarter-liter of oil and 3–5 liters of additional water.
Amman, the oasis dried up in the early 1990s, threatening After use, at least three out of four bottles in the United
this ecologically valuable site. Today international donors States are thrown away, and not recycled. That’s 30–40 billion
are helping Jordan’s government to find alternative sources containers per year (5 containers for every human being on
of water and restore this oasis, and to more efficiently man- Earth), and close to 1.5 million tons of plastic waste.
age groundwater withdrawals, as the water table has fallen As a result of the environmental impacts of bottled water, as
some 17 m (56 ft) over the past 20 years. of 2012 over 90 colleges and universities in the United States and 417

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