A river's journey from source to sea
A river is a connected system. Changes in gradient, discharge and load explain why its valley looks different from the source to the sea.
Part of your national curriculum
- Human and physical geography: Understand how geographical processes interact to create distinctive human and physical landscapes that change over time
- Human and physical geography: Understand rivers, coasts and glaciation and the physical processes that give rise to landscapes, and how they change over time
Lesson overview
What you'll learn in this lesson
Understand rivers, coasts and glaciation and the physical processes that give rise to landscapes, and how they change over time
Key learning points
- • The upper course
- • The middle course
- • The lower course
- • Reading the whole system
This lesson at a glance
- 30 minutes
- 14 parts to scroll through
- 3 quick checks
- Marked quiz at the end
- Gentle pace: short sittings with pauses
Words to know
Scroll down — the lesson carries on below
Watch & discover
Part 1 of 14
Watch first
A river's journey from source to sea
An English teaching video on this topic from Oxford Education. Watch it, then scroll down for the lesson.
In a nutshell
Understand rivers, coasts and glaciation and the physical processes that give rise to landscapes, and how they change over time
Learning cycle
Part 2 of 14
Learning cycle 1 of 2
Part 1 · The upper course
A short piece of teaching, then a check to make sure it has landed.
Explore the idea
Part 3 of 14
Learn
The upper course
Near the source, a steep gradient gives the river enough energy for vertical erosion. Hydraulic action and abrasion cut a narrow V-shaped valley. Where resistant rock overlies softer rock, uneven erosion can form a waterfall; undercutting leaves an overhang that collapses, so the waterfall retreats and leaves a gorge.
Explore the idea
Part 4 of 14
Learn
The middle course
Tributaries increase discharge and the channel becomes wider and deeper. Faster flow on the outside of a bend erodes a river cliff, while slower flow on the inside deposits material on a slip-off slope. The bend grows into a meander.
Quick check
Part 5 of 14
Quick check
Why does a waterfall retreat upstream?
Reset break
Part 6 of 14
Pause
That's sitting 1 of 2 done
Stretch, get a drink, look out of the window. There is no timer and nothing is counting down — your place is saved, so you can come back in five minutes or tomorrow.
Quick check
Part 7 of 14
Quick check
Where is flow usually fastest on a meander?
Learning cycle
Part 8 of 14
Learning cycle 2 of 2
Part 2 · The lower course
A short piece of teaching, then a check to make sure it has landed.
Explore the idea
Part 9 of 14
Learn
The lower course
Near the mouth, lateral erosion and repeated flooding create a wide, flat floodplain. During a flood, the heaviest load is dropped first beside the channel, building natural levees. If a meander neck is cut through, deposition can seal the old bend into an oxbow lake.
Explore the idea
Part 10 of 14
Learn
Reading the whole system
A long profile usually becomes gentler downstream, while channel width, depth and average discharge increase. These are broad patterns rather than rules: geology, storms and human changes can alter any reach of the river.
Quick check
Part 11 of 14
Quick check
What usually increases from source to mouth?
Challenge round
Part 12 of 14
Game · Sort it
Which of these are true?
Drag each card into the right column. Tap a card first if dragging is fiddly.
True
Not true
Mastery quiz
Part 13 of 14
Marked quiz
End of lesson quiz: A river's journey from source to sea
3 questions, marked with the reasoning shown. No timer.
1. Why does a waterfall retreat upstream?
2. Where is flow usually fastest on a meander?
3. What usually increases from source to mouth?
Lesson round-up
Part 14 of 14
Lesson round-up
Ready when you are
Quiz score
Not sat
Games
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Points this lesson
0
Best run
0 in a row
Luna: 0 out of 3 on the practice checks. Only if you feel up to it — one more?
Ask LunaDo the work
Your written work for this lesson
This is the part you'd do in your book at school. Pick the pieces below, write here or on paper, and photograph anything you draw or work out.
Flooding on the River Calder
The town of Harbrook sits where a steep valley opens onto a flat floodplain. In December 2015, 120 mm of rain fell in 36 hours onto ground that was already saturated. The river rose 2.4 m in five hours, and 380 homes and 54 businesses flooded. Two roads and the railway closed for eleven days.
Geographers pointed to physical causes — steep slopes, impermeable rock, heavy rainfall — and human causes: moorland drained upstream, new housing built on the floodplain, and drains designed for smaller storms.
Since then the town has planted 40 hectares of woodland upstream, built leaky dams in small streams, and raised flood walls to 1.8 m. In the storm of 2020 the peak river level was 0.3 m lower and 40 homes flooded, not 380.
Written for Good Learning Co.
Reading questions
- List two physical and two human causes of the 2015 flood.
- Explain how planting woodland upstream lowers the river's peak level.
- Using the figures, judge how successful the scheme has been. Quote data in your answer.
Case study notes
WritingWrite the place, the facts and the figures from this lesson so you can revise them later.
Half a page
Explain answer
WritingAnswer in full sentences, giving causes and effects. Use one figure or place name as evidence.
8–10 sentences
Map or sketch
DiagramDraw the map, cross-section or field sketch with a key, title and labels, then photograph it.
1 map with a key
Data work
Working outPlot your figures as a graph on paper and write one sentence about the pattern.
1 graph + 1 sentence
Saved as you type.
Part 1 of 14 · Watch & discover
How this is going
- Not looked at yet
Understand how geographical processes interact to create distinctive human and physical landscapes that change over time
- Not looked at yet
Understand rivers, coasts and glaciation and the physical processes that give rise to landscapes, and how they change over time