The Flow of Fresh Water

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Chapter 11
The Flow of Fresh Water
Preview
Section 1 The Active River Section 2 Stream
and River Deposits Section 3 Water
Underground Section 4 Using Water Wisely
Concept Mapping
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Section 1 The Active River
Chapter 11
Bellringer
Discuss whether a river can be said to have a
source and describe what a rivers source might
look like.
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Section 1 The Active River
Chapter 11
Objectives

• Describe how moving water shapes the surface of
  the Earth by the process of erosion.
• Explain how water moves through the water cycle.
• Describe a watershed.
• Explain three factors that affect the rate of
  stream erosion.
• Identify four ways that rivers are described.

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Section 1 The Active River
Chapter 11
Rivers Agents of Erosion

• What Is Erosion? Erosion is the process by which
  soil and sediment are transported from one
  location to another.
• Water and Erosion Water is a major agent of
  erosion. Rivers often carry eroded materials long
  distances.

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Section 1 The Active River
Chapter 11
The Water Cycle

• What Is the Water Cycle? The water cycle is the
  continuous movement of Earths water from the
  ocean to the atmosphere to the land and back to
  the ocean.
• Powering the Water Cycle The water cycle is
  driven by energy from the sun.

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Section 1 The Active River
Chapter 11
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Section 1 The Active River
Chapter 11
Water Cycle
Click below to watch the Visual Concept.
Visual Concept
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Section 1 The Active River
Chapter 11
River Systems

• Tributaries A stream that flows into a lake or
  into a larger stream is called a tributary.
• Watersheds A watershed, or drainage basin, is the
  area of land that is drained by a water system.

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Section 1 The Active River
Chapter 11
Tributary, River System, and Drainage Basin
Click below to watch the Visual Concept.
Visual Concept
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Section 1 The Active River
Chapter 11
Stream Erosion

• Gradient Gradient is the measure of the change in
  elevation over a certain distance.
• Discharge The amount of water that a stream or
  river carries in a given amount of time is called
  discharge.
• Load The materials carried by a stream are called
  the streams load.

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Section 1 The Active River
Chapter 11
Gradient
Click below to watch the Visual Concept.
Visual Concept
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Section 1 The Active River
Chapter 11
Discharge
Click below to watch the Visual Concept.
Visual Concept
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Section 1 The Active River
Chapter 11
Types of Load
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Visual Concept
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Section 1 The Active River
Chapter 11
The Stages of a River

• Youthful Rivers A youthful river erodes its
  channel deeper rather than wider.
• Mature Rivers A mature river erodes its channel
  wider rather than deeper.

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Section 1 The Active River
Chapter 11
The Stages of a River, continued

• Old Rivers An old river has a low gradient and
  little erosive energy.
• Rejuvenated Rivers Rejuvenated rivers are found
  where the land is raised by tectonic activity.

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Section 2 Stream and River Deposits
Chapter 11
Bellringer
Even though flooding along rivers is potentially
harmful, many farms are located near rivers. Why
do people build farms along rivers? Record your
answers in your science journal.
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Section 2 Stream and River Deposits
Chapter 11
Objectives

• Describe the four different types of stream
  deposits.
• Describe how the deposition of sediment affects
  the land.

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Section 2 Stream and River Deposits
Chapter 11
Deposition in Water

• Placer Deposits Heavy minerals are sometimes
  deposited at places in a river where the current
  slows down. This kind of sediment is called a
  placer deposit.
• Delta As its current slows, a river often
  deposits its load in a fan-shaped pattern called
  a delta.

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Section 2 Stream and River Deposits
Chapter 11
Deposition on Land

• Floodplains The area along a river that forms
  from sediment deposited when a river overflows
  its banks is called a floodplain.
• Flooding Dangers Floods can damage property and
  cause a loss of lives. Dams and levees are often
  used to prevent flooding.

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Section 3 Water Underground
Chapter 11
Bellringer
A family lives 50 km from the nearest stream or
lake and gets water from a well. Where does the
water in the well come from?
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Section 3 Water Underground
Chapter 11
Objectives

• Identify and describe the location of the water
  table.
• Describe an aquifer.
• Explain the difference between a spring and a
  well.
• Explain how caves and sinkholes form as a result
  of erosion and deposition.

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Section 3 Water Underground
Chapter 11
The Location of Groundwater

• The Water Table The zone of aeration and the zone
  of saturation meet at a boundary known as the
  water table.

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Chapter 11
Section 3 Water Underground
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Section 3 Water Underground
Chapter 11
Aquifers

• Porosity The percentage of open space between
  individual rocks is called porosity.
• Permeability A rocks ability to let water pass
  through is called permeability.

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Section 3 Water Underground
Chapter 11
Permeable and Impermeable Rocks
Click below to watch the Visual Concept.
Visual Concept
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Section 3 Water Underground
Chapter 11
Aquifers, continued

• Aquifer Geology and Geography The best aquifers
  usually form in permeable materials.
• Recharge Zones The ground surface where water
  enters an aquifer is called the recharge zone.

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Chapter 11
Section 3 Water Underground
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Section 3 Water Underground
Chapter 11
Springs and Wells

• Artesian Springs An artesian spring is a spring
  whose water flows from a crack in the cap rock of
  an aquifer.
• Wells A human-made hole that is deeper than the
  level of the water table is called a well.

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Section 3 Water Underground
Chapter 11
Aquifers and Artesian Springs
Click below to watch the Visual Concept.
Visual Concept
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Section 3 Water Underground
Chapter 11
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Section 3 Water Underground
Chapter 11
Well
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Visual Concept
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Section 3 Water Underground
Chapter 11
Underground Erosion and Deposition

• Cave Formations Although caves are formed by
  erosion, they also so signs of deposition, such
  as stalagmites.
• Sinkholes The roof of a cave can collapse, which
  leaves a circular depression called a sinkhole.

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Section 4 Using Water Wisely
Chapter 11
Bellringer
While hiking, you realize your canteen is almost
empty. Why should you not fill the canteen with
water from a nearby stream? Record your response
in your science journal.
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Section 4 Using Water Wisely
Chapter 11
Objectives

• Identify two forms of water pollution.
• Explain how the properties of water influence the
  health of a water system.
• Describe two ways that wastewater can be treated.
• Describe how water is used and how water can be
  conserved in industry, in agriculture, and at
  home.

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Section 4 Using Water Wisely
Chapter 11
Water Pollution

• What Is Pollution? Pollution is the introduction
  of harmful substances into the environment.
• Point-Source and Nonpoint-Source Pollution
  Pollution that comes from one specific site is
  called point-source pollution. Nonpoint-source
  pollution is pollution that comes from many
  sources.

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Section 4 Using Water Wisely
Chapter 11
Point-Source and Nonpoint-Source Pollution
Click below to watch the Visual Concept.
Visual Concept
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Section 4 Using Water Wisely
Chapter 11
Health of a Water System

• Dissolved Oxygen Fish and other organisms that
  live in water need dissolved oxygen in the water
  to live.
• Nitrates Elevated nitrate levels in water can be
  harmful to organisms because they lower the
  amount of dissolved oxygen in the water.
• Alkalinity Alkalinity refers to waters ability
  to neutralize acid. Acid rain can lower waters
  alkalinity.

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Section 4 Using Water Wisely
Chapter 11
Cleaning Polluted Water

• Primary Treatment In primary treatment, dirty
  water is passed through a large screen to catch
  solid objects.
• Secondary Treatment In secondary treatment, the
  water is sent to an aeration tank, where it is
  mixed with oxygen and bacteria.
• Another Way to Clean Wastewater A septic tank is
  a large underground tank that cleans wastewater
  from a household.

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Chapter 11
Section 4 Using Water Wisely
Sewage Treatment Plant
Click below to watch the Visual Concept.
Visual Concept
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Section 4 Using Water Wisely
Chapter 11
Where the Water Goes

• Water in Industry About 19 of water used in the
  world is used for industrial purposes.
• Water in Agriculture Water must be used in
  agriculture to facilitate plant growth.
• Conserving Water at Home Many people save water
  by installing low-flow shower heads and low-flush
  toilets.

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Section 4 Using Water Wisely
Chapter 11
How Do You Use Water?
The average household in the United States uses
about 100 gal of water per day. This circle graph
shows some common uses of these 100 gal.
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The Flow of Fresh Water
Chapter 11
Concept Mapping
Use the terms below to complete the concept map
on the next slide.
zone of aeration zone of saturation water table ground water surface water porosity aquifer

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The Flow of Fresh Water
Chapter 11
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The Flow of Fresh Water
Chapter 11