Chapter 14 Water
Resources
Do Now:
In your notebook answer the following
questions:
• Where do you think you would find freshwater
on earth?
• Where would you find saltwater?
• Where does all freshwater originate from?
• Where is the most freshwater located?
Lesson 14.1 Earth: The Water Planet
Where Is Our Water?
• Fresh water 2.5%renewable resource
(water cycle) & limited
resource(most is
salt/frozen).97.5 %
salt
• distributed unequally.
Did You Know? If all Earth’s water were in a two-
liter bottle, only about two capfuls would be
fresh, liquid water.
• Amount of water used
depends on where
they live & the time of
year.
Lesson 14.1 Earth: The Water Planet
Surface Water
• Surface water- still
bodies of water & river
systems. sources:
rainfall, melting snow,
glaciers, ice caps
• Runoff- water that flows
over land & not been
absorbed by ground
Watersheds of the U.S.
Did You Know? The Mississippi River Basin
covers 3 million square kilometers (1.2 million sq mi),
making it the third largest watershed in the world. It
drains 41% of the land area of the contiguous US.
• Watersheds- all of the
land area that supplies
water to a river system.
Drainage basin
Lesson 14.1 Earth: The Water Planet
Groundwater
• Groundwater-seeps
through soil &
contained in
underground aquifers.
• Aquifers -permeable
layers of rock & soil
that hold water.
Layers with few or no
pores -Impermeable
• water table separates
the zone of saturation
from the zone of
aeration.
An Aquifer
Did You Know? The average age of groundwater
is 1400 years. Groundwater recharges very slowly.
Well
• Water tables naturally rise- creating springs
• Ground water can burst to surface- geysers.
• Digging to reach groundwater-well
• Wells are dug deep into zone of saturation so they will
not dry out.
Quick Check
• 1.Fresh Water is considered a renewable resource
because…….
• 2.Fresh water is considered a limited resource
because…….
• 3. An impermeable layer of rock has no
_________________.
• 4. Drainage basins are also called___________.
14.2 Uses of Freshwater
Lesson 14.2 Uses of Fresh Water
How We Use Water
• Main uses of fresh water:
• Agricultural
• Industrial
• Personal
Did You Know? The average
American uses 250 L of fresh water a
day for personal uses, such as
bathing and brushing teeth.
Lesson 14.2 Uses of Fresh Water
Using Surface Water
• Most freshwater used in the U.S. is surface water.
• Surface water- diverted by canals & dams. (water diversion) Artificial
Reservoirs- store water
• Drought and overuse -caused significant surface water depletion.
Did You Know? The Aral
Sea was once the fourth
largest body of fresh water.
The problem with Dams
• •Costs:
• •Fisheries Decline
• •Habitat alteration
• •Population displacement
• •Sediment Capture
• •Loss of fertile farmland
• •Risk of failure
• •Lost recreational opportunities
Lesson 14.2 Uses of Fresh Water
Using Groundwater
• 68%-U.S. used for irrigation
• Groundwater mining turns it into a nonrenewable
resource (it is withdrawn from the ground faster
than it can be replaced)
• When groundwater is
depleted, the falling water
tables can cause cities to
sink, and undrinkable
saltwater to move into the
depleted aquifers.
Lesson 14.2 Uses of Fresh Water
Solutions to Freshwater Depletion
• Increase supply:
• Desalination: “Making”
fresh water by removing
salt from saltwater.
• Decrease demand:
• Agricultural: Dripirrigation, climateappropriate plants
• Industrial: Waterconserving processes,
recycling wastewater to
cool machinery.
• Personal: Xeriscaping,
water conservation
Desalination
Pg. 434 #1-4 in notebook
14.3 Water Pollution
Lesson 14.3 Water Pollution
Types of Water Pollution
• Point-source pollution:
From a distinct location, like
a factory or sewer pipe
• Nonpoint-source
pollution: From many
places spread over a large
area, such as when
snowmelt runoff picks up
pollutants along its pathagricultural feed lots
Point source oil pollution
Oil after a spill, Trinity Bay, Texas
• NUTRIENT POLLUTION
• Eutrophication – occurs naturally when nutrients build up in
a body of water.
• Freshwater- involves build up of phosphorus Growth rate of
plants algae Increase. More growthmore decomposition
as algae and plants die. Decomposition requires oxygen so
oxygen in water decreases. (Naturally can take centuries)
Artificial Eutrophication
• (Cultural Eutrophication) excessive nutrients added to
bodies of water through runoff causing algal bloom
• done by human activities (fertilizer, detergents)
• reduces the amount of oxygen for fish and other
organisms suffocating them.
Wastewater- water used by people in some way
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Water pollution
Sewage, industrial waste, oil, pesticides and fertilizers all
pollute water.
Fertilizers and sewage can easily be washed into rivers,
streams and lakes. The nutrients, phosphates and nitrates in
these substances cause eutrophication.
Eutrophication is the
accumulation of
nutrients in water, which
causes excessive algal
growth. This leads to a
reduction in oxygen
levels and the death of
aquatic life.
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Eutrophication
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Eutrophication
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Lesson 14.3 Water Pollution
Toxic Chemical Pollution
• harmful chemicals released
into waterways
• plant remains or chemicals
(pesticides or detergents) &
materials made from
petroleum -all from
nonpoint sources.
• Harms ecosystems and
causes human health
problems
Do Now: Use page 438 in Text
book for help. Answer in your
notebooks
• What are pathogens?(Try putting it in your own words)
• True or False: Biological pollution causes more human
health problems than any other type of water pollution
• How many of the diseases listed in the chart are
caused by bacteria? (Look at the chart for the answer)
Lesson 14.3 Water Pollution
Biological Pollution
• Pathogens disease-causing organisms
are from nonpoint sources like animal
feces and sewage.
• causes more human health problems
than any other form of water pollution.
• Water treatment reduces biological
pollution.
Cholera bacteria
Did You Know? Giardiasis is
the most common form of
waterborne disease in the U.S.
Lesson 14.3 Water Pollution
Groundwater Pollution
• natural sources- surface pollutants
leaching through soil, and leaky
underground structures.
• Chemicals break down more slowly
in groundwater than in surface water.
Recycling can take 100 to 1000
years
• Deep underground dispersed
through large areas of rock
• Pollutants stick to aquifer
Did You Know? The EPA repairs and replaces leaky
underground gas storage tanks to reduce groundwater
pollution. Over the last 25 years, over 1.7 million tanks have
Acid drainage from a coal mine
Lesson 14.3 Water Pollution
Houston Oil Spill – March 2014
Ocean Water Pollution
• Oil pollution-comes from many
widely spread small sources.
Natural seeps -largest single
source.
• Ocean organisms bioaccumulate
mercury pollution.
A 2004 oil spill off the Alaskan coast
Did You Know? According to the U.S. Oil
Pollution Act of 1990, by 2015, all oil
tankers in U.S. waters must have double
hulls to help prevent against leaks.
• Nutrient pollution can cause red
tides.
• Many pollutants come from
land activities
• Plastics and marine life
Thermal Pollution
• raising of water temp b/c power plants discharge their
warm water from cooling center into a lake or stream.
Lesson 14.3 Water Pollution
Controlling Water Pollution
• Government regulation
decreases water pollution.
• The Clean Water Act
• Set water pollution
standards
• Required permits to release
point-source pollution
• Funded sewage treatment
plant construction
Lake Erie
Did You Know? The Great Lakes show that humans can
change their ways and clean up trouble spots. In the
1970s, Lake Erie was declared “dead” but is now home
to some flourishing species, especially the walleye.
Lesson 14.3 Water Pollution
Water Treatment
• Drinking water-treated to remove pollutants before
humans consume it.
• Wastewater-treated to remove pollutants before humanused water is released back to the environment.
Septic systems are the most popular method of
wastewater disposal in rural areas of the U.S.