1. Rivers
What the Specification says
Fluvial processes which result in distinctive landforms
Long and cross profiles, processes of erosion (hydraulic power, corrosion, corrasion, attrition), transport
(traction, saltation, suspension, solution) and deposition.The characteristics and formation of waterfalls, gorges,
meanders, ox-bow lakes, levees, flood plains and deltas. Recognise and describe fluvial features on Ordnance
Survey maps and photographs. How a river profile changes downstream and the relative importance of the
processes at work such as the typical V shaped valley in the upper course where vertical corrasion dominates.
Students will be expected to be able to name an example, describe each feature and to explain its
formation making reference to the processes at work.
The interaction between people and fluvial environments
River basin management issues – the causes and effects of flooding in river basins in the context of both LEDCs
and MEDCs.The short, medium and long term strategies used to attempt to manage the floods. Contemporary
issues concerning use of ‘hard’ v ‘soft’ strategies and attempts to achieve sustainability.The social, economic,
environmental and political issues that have an impact upon strategies and the values and attitudes of interested
groups. River basin management issues should be studied in the context of both LEDCs e.g. Bangladesh and
MEDCs e.g. the European floods of the 1990s. One case study from the MEDW and LEDW should be chosen to
study the physical and human
causes of flooding and the impact of the floods. TV news is a good source of up to date information. Flood
management should include efforts to prevent flooding and strategies used to ameliorate the impact. Candidates
should be aware of how and why the methods used are different between the LEDW and MEDW and now
currently there is a move away from hard engineering e.g. dams on the Colorado to softer approaches e.g. flood
plain zoning, improved warning system.
1) River Courses
Upper course of the river
Interlocking Spurs - caused by erosion, Formed in a V - shaped valley (a series of ridges that rise above the river
which twist and turn through a valley)
Waterfall - Caused by layers of soft and hard rock. The layer of soft rock following the hard rock begins to
erode, which forms a drop where the river drops down to the level of the soft rock. This repeats over time to
form a large drop at the edge of the hard rock band. Where the water crashes into the band of soft rock, a
plunge pool is formed. Here the angular fragments that have been eroded upstream fall into the plunge pool,
and rotate with the force of the falling water. Over time this erodes the plunge pool and the waterfall retreats to
leave a gorge.
Drainage basin - The area of land from which a river and its tributaries drain its water from. The boundary of a
drainage basin is usually marked by a ridge of high land, called a watershed.
Gorge - See above
Rapids - Caused by alternating bands of soft and hard rock. As the soft rock erodes, several bumps and ridges
form, making the water writhe and churn.

2. Middle course of the river
Meanders - Bends and curves in the river that undulate back and forth up and down the gently sloping wide
valley. Differential erosion causes these meanders to move, and they form slip off slopes and river cliffs. The
river flows fastest round the river cliff side, producing alluvium (sediment) that is then deposited on the slip off
slope.
Lower course of the river
River delta -
This can only
be formed in an
area of water
with no strong
residual
currents, in an
estuary or
mouth of a
river. They
usually are
formed in small
enclosed bodies
of water, e.g.
The Rhone
Delta or the
Nile Delta. This
area of the river
is where the
alluvium the
river carries is
deposited and
starts to form
small
sandbanks, and
plains in the
sea, and
sometimes
areas of wildlife
create habitats.
Floodplain - A
wide area of
land adjacent to
the river either
side of it when
the river starts
to widen. It is
affected by
erosion and
deposition. The
floodplain can
be eroded by

3. meanders The Nile Delta, pictured above, shows distinct distributaries as alluvium is deposited by the slowing water.
migrating
downstream,
but also
deposited upon
by slip off
slopes on
meanders. The
majority of
deposition
occurs in
flooding where
the river bursts
its banks and
spills over onto
the floodplain,
depositing all its
carried
alluvium. Over
time these build
up to great
masses of
alluvium, acting
as fertile land
for crops.
Ox-Bow Lake -
These lakes
form due to the
constant
erosion of the
river cliffs.
When a bend in
the meander
loops back on
itself, the river
cliffs are eroded
further to cut
through the
bend and the
river begins to
flow through
the neck of
land, which cuts
off the
meander. Over
more time
alluvium builds
up blocking off
the meander
and forming an
ox-bow lake. If
the water in the

4. ox-bow lake
dries out , a
meander scar is
left.
Levées- These
occur on the
sides of the
river, formed of
alluvium. They
are natural
embankments
that can reach
up to several
metres higher
than the
floodplain.
These are
formed over
numerous
cycles of
flooding, in
which material
(alluvium) is
deposited by
the river as the
water loses
velocity having
become shallow
as the river
floods. These
are only formed
on the banks of
slow-flowing
rivers.
2) River Processes
1. Hydraulic Power - The force of water against the bed and banks of a river. Hydraulic power increases in
force when the river floods. Hydraulic force erodes the sides and bed of a river, often removing material
from them.
2. Corrasion - Also known as Abrasion. The river carries alluvial material along the courses of the river. The
suspended material is thrown against the bed and banks of the river, causing erosion. This is corrasion.
3. Corrosion - Soluble materials, such as limestone (calcium carbonate) begin to dissolve in acidic river
water. This causes corrosion of the alluvium.
4. Attrition - The material suspended in the water collides with other suspended alluvial materials, causing
erosion of the materials, which is called attrition.
5. Traction - Large boulders rolling along the bottom of the river bed.
6. Saltation - Smaller pebbles bouncing along river bed. They are lifted and dropped along the course of
the river.
7. Suspension - Finer sand and silt is carried by the river giving it a brown appearance.
8. Solution - Minerals such as limestone and chalk are dissolved in the water, thus they cannot be seen,
but are carried by the flow of the river.

5. 3) Human involvement in rivers
River Regimes
This is the difference in river flow at times of the year, normally used to precipitation in the river basin. At times
(the winter and spring months) the river reaches its maximum discharge. However when the water goes above
this level flooding usually occurs in the lower course with dramatic consequences. Flooding can be increased by
human activity in the river valley such as:
• Building towns and car parks & urban areas increasing surface flow and decreasing the permeability of
the land.
• Deforestation in the lower course of the river increases water in the ground flow, leading to more severe
floods.
• Occasional disasters e.g: burst dams, landslides and storms in the river basin.
In spite of this certain precautions can be taken to stop floods, known as management schemes. For example
cheap methods of preventing floods are planting trees to decrease ground flow, land use zonation to move
residential areas away from the river and an early warning system when heavy precipitation occurs. More
expensive solutions are to straighten river meanders to increase the velocity of discharge, dredging river beds to
increase volume of discharge and building dams/reservoirs to hold water and release water at a controlled rate.
4) Case Studies
Rhone Delta in Southern France
The River Rhone flows into the Mediterranean Sea. It has a source in the Alps, but has a major confluence at
Lyons with the River Saone. There is a large delta at the mouth of the River Rhone, where the sand and silt has
caused the river to split into two distributaries called the Grand Rhone and the Petit Rhone. These also have
many islands of silt and sand within them. Because of these islands, the Camargue is home to a wide variety of
wildlife. There are many varying types of human involvement. This includes farming, due to the fertile soil
caused by the Delta. There is also a lot of tourism, and civil engineering take place there.
River Tees in County Durham
The River Tees flows from high in the Pennines west into the North Sea. The Tees Valley itself forms a hub for
industrial activity, local tourism and agriculture in the area. The most important feature of this case study is the
human activity in the upper course of the river. Five major factors are of importance, and they will be key to
understanding exam questions
• Settlement and communications:- The steep land of a valley makes communications difficult, making
construction and employment in this sector weak. In these upland areas the population density is low, in
isolated farms and occasional villages
• Water supply:- As water quality is high, the Tees valleys acts as a local water supply. A good example of
local water storage is Cow Green Reservoir, which supplies the lower course with water, but also helps
contain excess rainfall to prevent flooding.
• Agriculture:- The major land use in the upper valley is agriculture and specifically sheep farming. Soils
are too thin and the valley is too steep for active machinery so at higher grounds, sheep freely roam
and graze. But below 400 metres fields are seen with traditional dry-stone walls and on gently sloping
land the occasional crop is grown or a small herd of dairy cattle
• Tourism:- Many local attractions continue to bring in tourists to the area. The waterfall High Force,
market towns, nature trails and footpaths, open moorland and shooting ranges are all good examples of
how visitors bring employment for hotels, information centres and restaurants. Yet tourism also has
negatives such as litter, the disrupting of livestock and crops, overcrowding, knocking over walls, traffic
congestion and erosion of paths.

6. • Industry:- There used to be a thriving lead mining industry in Upper Tees Valley, however this has
slowly died out, although the disused mines have now been converted into tourist areas. Nothing major
has replaced this industry, but there is some forestry and specialist craft work employment. A quarry at
Holwick is still functioning, mining Whinstone for use in roads. There is also one very large employer in
the region, Glaxo-Wellcome, a massive chemical and pharmaceutical manufacturer.
Mississippi River in East America
The Mississippi River flows through 10 states into the Gulf of Mexico. It is the fourth longest river in the world
and has a drainage basin covering most of the United States. During the autumn and winter of 1992 high rates
of rainfall and snowfall were recorded. This continued through the spring and summer where storms regularly
occurred over the same places again and again. This led to increased run off from the land in places where 48
inches of rain were recorded in 3 months. Over the summer of 1993 consistent heavy flooding was present, and
this led to the loss of 28 lives, 36,000 homes destroyed, 6,000,000 acres of farmland flooded, millions of tonnes
of silt and sand deposited in the city, and $10,000,000,000,000 of damage in the end. It was all caused by
engineers trying their best to stop flooding, by concreting the flood plain, and enforcing and strengthening
levees, but eventually, when the flood did occur, this just made it all worse, with no water absorbed by the
ground, and a much greater volume of water trapped behind the levees when they burst.