Ci sono molti meanders around Caersws because the river is now flowing across low land. The River Severn begins to wander from side to side across the valley floor. The main erosion seen here tends to be horizontal (sideways), rather than the vertical erosion seen in the mountains.

A meandro is a bend in a river. Meanders normally occur in the middle and lower courses where the water is moving more slowly.

Over long periods of time the shape of these meanders will change, due to erosione e deposizione.

The river has cut through a loop, forming an ox-bow lake

An ox-bow lake has formd here
The River Severn used to travel more to the right in the photo above, but has now broken through and changed course. Clicca sul old river bed in the photo above to have a closer look.

On the inside of the bend, where the river flow is slower, material is deposited.

The river meanders to the left.

Berty notices some stones and clumps of earth by the bank in the river.
Where do you think they came from?

Outside of bend where most erosion occurs

The force of the water erode and undercuts the river bank on the al di fuori of the bend where water flow has most energy (flows faster). The force of the water crashing into the bank is wearing away the river bank. This is even more noticeable when the Severn is in full flood.

The river continues to meander its way through the Caersws floodplain carving out S-shaped bends.

The photo above shows a meander belt

A meander belt is where there are several meanders occurring one after the other.

Follow this link to find out more about the ox-bow lake at Caersws

Meander Animation
A simple animation of a fairground ride to help pupils understand the concept of objects being thrown outwards on a bend.

Meander Animation
The basic features of how a meander is formed.

Vocabolario chiave

Erosione
L'erosione è il logoramento dei lati e del fondo dei fiumi dalla forza dell'acqua e del materiale trasportato dall'acqua.

Azione idraulica
This is like pointing a jets spray at the bank. The power and force of the water crashing into the river banks wears them away.

Meandro
A meander is a wide, looping bend in a river

sedimento
Il materiale che viene trasportato da un fiume e poi depositato.