In my report, I will investigate how well the Bradshaw model fits in river Caerfanell. In particular my report will focus on 3 sub questions;
1. How does the cross-sectional area of the river Caerfanell change with distance downstream?
2. How does the velocity change with distance downstream?
3. How does channel efficiency change with distance downstream?
Figure 1: Bradshaw Model shows the changes of river from Upstream to Downstream
According to the Bradshaw Model I would expect.
Discharge increases downstream because tributaries join the main river and increase amount of water in Main River. Cross-Section will increase as the river goes downstream, channel depth and width of the river increases due to abrasion.
Velocity will increase downstream as more water is added due to tributaries join the river. This means that less of the water is in contact with the bed of the river and backs so less energy is used to overcome friction.
The Load Quantity increases downstream due to increased discharge as a result river having more energy meaning that the river will be able to carry a heavier load.
The particle size decreases as discharge also decreases. As a result, the river is able to carry more of its load and so attrition and abrasion will take place.
Hydraulic Radius is s measure of how efficient channel is at transporting water and sediment. According to the Model, stream should increase in size and power. The channel bed should get less turbulent due to erosion. Hydraulic Radius is calculated by Cross-section divided by perimeter.
Figure B: A map of the UK showing where the Brecon Beacons is located.
What were we measuring and why
What exactly did we do
Why did we do what we did
What were the advantages and disadvantages of the method?