Perth Academy
Geography Department
Landscapes
Rivers and Their Valleys
RIVERS AND THEIR VALLEYS
Over 70% of the surface of the Earth is made up of water, of which approximately 3% is fresh water.
The Hydrological (water) Cycle
The hydrological cycle shows the transfer of water from the world’s oceans to the atmosphere and
back again.
Where does rain
come from?
Why do clouds
form?
Watch the following clip and then complete the task in pairs to complete your own water cycles.
http://www.youtube.com/watch?v=x2jPsfy2iq8
Task
Use the following clues to complete a water cycle with the person sitting beside
you:
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Rainwater that seeps into the ground (infiltration) is stored within the earth
Directly from the earth’s surface and freshwater storage
The release of water from plants into the atmosphere
The combined total of evaporation and transpiration
Channel water back to the oceans
Store 70% of the world’s water
Loss of water vapour from vegetation
Rain, hail, sleet and snow
Clouds form as water vapour cools
Perth Academy: Geography 2014
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Task
Now copy your completed diagram into your jotter under the heading “Hydrological
Cycle”.
Drainage Basins
The part of the water cycle which is of most interest to Geographers is the transfer of precipitation
(rainfall) back to the oceans via rivers (surface run-off). The area where rain falls and is channelled
back to seas and oceans by a number of rivers is called a drainage basin. As water flows downhill it
will depend where the rain falls which direction it will flow and into which river.
Task: Pop-up drainage basins
Complete this task in your jotter using templates, coloured pencils and instructions
from the powerpoint.
Perth Academy: Geography 2014
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Location of Main UK Rivers
Task
Use at atlas to find and label the main rivers of the UK on the map below. Shade the
rivers blue, then find the mountains closest to the source of each river, shade them
brown and label them. Remember to complete the key.
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Perth Academy: Geography 2014
River Processes
Watch “River Journey: River Forth”
Rivers are natural features and therefore vary greatly around the world. However, the majority
follow similar patterns as they flow from the source in the mountains to the mouth at the sea. They
influence and change the landscapes they flow through as well as affecting the lives of the people
who live beside them.
The model river can be split into three areas – the upper course, the middle course and the lower
course. Different river features are formed in each section of the river depending on whether the
major influence on the river is erosion, transportation or deposition:
upper
middle
lower
Erosion is the wearing away of the land and happens mainly in the upper course of the river.
Transportation is the moving of eroded material from one place to another and happens mainly in
the middle course of a river.
Deposition is the laying down of eroded material as the river no longer has enough energy to carry
it. This is a feature of the lower course of a river.
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The Upper Course of a River
In the upper course of a river the slopes are very steep which means that water flows very quickly
downhill so the river has a lot of energy. Lots of erosion takes place in the upper course as a result.
There are different types of erosion:
Corrasion is the wearing away of the river bed and banks by the action of river load (rock material)
rubbing against the bank and bed. It can be described as a ‘sand-papering’ effect.
Attrition is the breaking of rocks into smaller fragments which are larger in number. This happens
when rocks in the river collide with one another.
Hydraulic Action is erosion by the sheer force of the water.
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Corrosion is the chemical wearing away of rock.
These different forms of erosion work together to allow the river to carve its way through the
landscape, creating a variety of upper course features.
Perth Academy: Geography 2014
The Main Characteristics of a River in the Upper Course
Task
Watch BBC ‘River Severn: Upper Course’ and ‘Planet Earth: Angel Falls’ clips and describe the
movement of water, what the river looks like and any features found in the upper course.
In the upper course of a river it is very narrow and fast flowing due to the steep slopes. This gives the
water a lot of energy to both erode material and to carry it away. The least amount of erosion of
river material (the river load) happens closest to the source, so rocks in the river tend to be large,
jagged and angular at this point. The river will erode most during times of flood when the volume of
water in the river increases, giving it more power.
The main features of the upper course of a river are:
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Source
V-shape valley
Waterfall
Interlocking Spurs
Tributary
Confluence
You will need to know these words and be able to explain how V-shape valleys and waterfalls are
formed.
V-shape Valley Formation
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Task
Copy the above diagram into your notes and then use it to explain, using sentences and
paragraphs, how a V-shape valley is formed.
Waterfall Formation
Task
Can you name the waterfall in the picture
to the left?
Why do
waterfalls
form?
Watch ‘Planet Earth: Freshwater’ clip and
note down any words you think of to
describe the waterfall shown in the film.
Remember to get its name!
Task
Watch the following clip from the BBC on how waterfalls are formed.
http://www.bbc.co.uk/learningzone/clips/waterfalls-plunge-pools-and-potholes/404.html
Perth Academy: Geography 2014
INSERT WATERFALL DIAGRAM
(FROM SCAN) HERE THAT PUPILS
CAN DRAW IN JOTTERS AND
ANNOTATE
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Draw and label the diagram above, using Figure 15.3
on p.263 of “New Wider World” to help you.
Using the labels on your diagram, write this paragraph in your jotter and fill in the
missing words, underlining them to show their importance. This is what you will be
expected to do to when asked to explain the formation of a waterfall.
Waterfalls form when a river flows over an area of ________ rock which overlies
________ rock. As softer rock is eroded more ___________ than harder rock, the ‘cap
rock’ gets undercut as the softer rock is worn away by ________________
___________. This is known as ________________ erosion. The undercutting of the
harder rock means that an _______________ develops which eventually collapses due
to the rock being unsupported. Large, __________ rocks fall into the base of the
waterfall where they are swirled around by the force of the water further eroding the
softer rock at the back wall of the waterfall. This process of erosion by rocks is called
___________ and also erodes the base of the waterfall to help form a _____________
___________. As this process continues over time the waterfall appears to
___________ upstream (towards the source), forming a steep sided _____________.
Word Bank
gorge
differential
corrasion
softer
hydraulic
harder
overhang
retreat
plunge
easily
pool
angular
action
Perth Academy: Geography 2014
The Middle Course of a River
Transportation is the movement of eroded material (in the case of a river from the upper course to
the lower course). The material will include large angular rocks, smoothed pebbles and sand
particles depending on which course of the river is being studied. There are four main ways in which
rivers move particles within them:
Traction is when large boulders are rolled along the bed of the river.
Saltation is when smaller and lighter stones and pebbles appear to ‘bounce’ along the river bed.
Suspension is when lighter and finer material is carried along within the river by the current. It is this
material that can make rivers look brown or red in colour.
Solution is when the particles in the river have dissolved, much like salt in sea water or sugar in
coffee which cannot be seen but can be tasted.
The Main Characteristics of a River in the Middle Course
Task
Watch the following clip from the BBC showing the River Tay in its middle course
http://www.bbc.co.uk/learningzone/clips/river-tay-middle-course/4312.html
In the middle course of a river it is coming down from the mountains so the landscape is starting to
flatten and therefore the river flows through areas of much gentler slopes. As a result, the river
flows more slowly than the upper course. The river will have more water as more tributaries have
joined the main river so the river itself is wider and deeper. The valley has also widened and as the
river has less energy it starts to meander across the valley. As the river has less energy this is mainly
a transportation phase. More erosion has happened so attrition and corrasion mean that there are
more rocks in the river but they are smaller and more rounded than before (pebbles).
The main features of the middle course of a river are:
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Meanders
River cliff
River beach
You will need to know these
words and be able to
explain how they form.
Perth Academy: Geography 2014
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Meander Formation
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Task: Problem Based Learning
“How does a meander form?”
In groups of 3, you are going to find out the answer to the above question.
 Firstly, discuss in your groups what you already know about rivers and create a
spider diagram to show this.
 Then discuss what you still need to find out to enable you to answer this problem
and create a spider diagram from this. Everyone should have these diagrams in
their jotters!
 Finally, discuss where you might be able to obtain the information you need and
be ready to discuss this with the class.
 Allocate a task to each member of the group which they have the responsibility
to research and complete.
 Your teacher will help provide you with resources and ICT equipment.
 Create a presentation of your own choosing to explain how meanders are
formed. All work must be in your own words!
Task
Watch the following clip to help understand the movement of water in a meander:
http://www.youtube.com/watch?v=skCqy3k1KcM
Perth Academy: Geography 2014
The Lower Course of a River
The river in its lower course is now flowing over very flat land as it gets closer to the sea. The river is
moving very slowly and has little energy to carry the material which has been transported and
eroded from the start of its journey in the mountains. Therefore, deposition occurs in the lower
course. The river itself has large meanders across a wide floodplain. The river load has been eroded
so much that it contains mainly fine sand and silt which are even smaller particles that are greater in
number than the pebbles of the middle course. When the river floods this is deposited on the
floodplain as fertile alluvium.
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The Main Characteristics of the Lower Course
Task
Watch the following clips from the BBC showing the River Severn from source to mouth:
http://www.bbc.co.uk/learningzone/clips/the-river-severn-upper-course/3076.html
http://www.bbc.co.uk/learningzone/clips/the-river-severn-the-lower-course/3077.html
The main features of the lower course of a river are:
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Floodplain
Ox-bow lake
Levée
Delta
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Ox-bow Lake Formation
Ox-bow lakes are former meanders which have been cut-off from the main river channel by the
processes of erosion and deposition.
The key to understanding why an ox-bow lake forms is to consider the following questions:
Where does
erosion
happen in a
meander?
Where is the
slowest flow
around a river
bend?
When does a river
have its greatest
erosive power?
Task
Watch the following BBC clip to gain an understanding of how an ox-bow lake forms:
http://www.bbc.co.uk/learningzone/clips/405/
Task
Now use the following words to write a paragraph in your jotter explaining how an ox-bow
lake is formed.
erosion
sediment
flood
neck
fastest
slowest
dry
cut-off
Perth Academy: Geography 2014
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Levée Formation
A levée can form naturally or can be man-made to help prevent the flooding of a river. The
Mississippi River is a good example of where artificial levées have been constructed as part of a flood
management project.
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A natural levée forms as a river floods and deposits layers of sand and silt across the flood plain. The
largest particles are deposited first and so build up beside the river banks forming embankments.
These will build up over successive floods. The fine particles of alluvium are spread across the
floodplain providing fertile alluvium for farming.
Perth Academy: Geography 2014
LAND USE
Task
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Watch the River Tees video and note down any ways that the land is used by people.
Split your jotter page into 3 columns, entitled upper, middle and lower. Sort the land uses
that you have noted down into each column. (Some may be in more than 1 column!)
Thinking
Task
Describe the journey of a river from source to mouth describing the various ways in which
the land (or the river itself) is used.
This is an individual creative writing task where you will write your story as if you are the
water in the river. Your story should be one page of A4 in length and describe at least two
ways in which the river is used in both the upper, middle and lower courses. A well written
story will use good adjectives, paragraphs and full sentences. It will also include river
features that the water will pass by or through.
You may wish to draw a spider diagram to help you organise your thoughts.
Inspiration
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Land Use Conflicts
Conflict:
1. to come into collision or disagreement; be contradictory, at variance, or in opposition; clash.
2. to fight or contend; do battle.
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Rivers and their valleys are used for a variety of different activities, such as fishing and kayaking,
which conflict with one another. Both sets of people have equal right to use the river as it is publicly
owned, so who gets to use the river?
Solutions
Various strategies have been put in place to try to alleviate these land use conflicts such as putting
additional litter bins in tourist areas or enforcing speed limits on the water.
Task
In the upper, middle and lower courses, note down any of the land uses that you have
studied that would come into conflict with one another e.g. kayaking and fishing in the
upper course.
You will now complete a carousel learning activity where you will teach other members of
the class about land use conflicts and some potential solutions to these.
Perth Academy: Geography 2014
Ordnance Survey
What does a
waterfall look
like on a map?
How can I tell
which
direction the
river flows in?
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You will need to be able to recognise the following features on an Ordnance Survey map:
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Waterfall
Gorge
Tributary
Confluence
Meander
Straight
Oxbow Lake
River Island (eyot)
Tidal or Non-tidal rivers
Task
Working in pairs, use the Worcester map, to try to find the features listed above. As rivers
are natural processes, they will not all show every feature.
Write down a 6 figure grid reference for each feature found.
You will also need to be able to use the map skills you have previously learned in Geography (scale,
contours, compass direction and grid references) to describe:
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Valley Shape
Valley Height
Valley width
River Width
Direction of Flow
Task
Find the height, shape and width of the valley of the River Teme. Comment on the width of
the river and if it changes along its course. Finally find the direction the river flows in.
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All of this information can all be put together to describe a river and its valley between two points.
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Task
Use the Preston OS map to describe the physical features of the River Ribble and its valley
between 590305 and 450277.
Extension Task – Think!
Find the M6 to the east of Preston.
Use your knowledge of map symbols to describe how road engineers overcame the
problems caused by the landscape between Junction 30 (5726) and Junction 32 (5434).
Give a 4 figure grid
reference for this
picture.
What direction are
you looking towards
in this picture?
Perth Academy: Geography 2014