Edexcel B River Investigation: Debden Brook
This is the pre-course activity for your GCSE fieldwork trip. Complete the handout and remember to bring it with you on the trip!
Investigation Title:
To investigate how and why drainage basin and channel characteristics influence flood risk for people and property along Debden Brook.
Getting started
Work through the slideshow below to revise some background geographical knowledge that will support this investigation. Key terms are in bold; make sure you know these and if you aren't sure of their meaning, make a glossary for yourself to help you remember.
Extension: The Bradshaw model
The diagram below is called the Bradshaw model. You should already have studied the river long profile and looked at how processes, characteristics and landforms change downstream. If you would like to know a bit more of the geographical theory behind rivers though, the Bradshaw model can help us understand how this change happens.
By now you might have an idea of what might change as we go downstream, but what about on Debden Brook?
Debden Brook
In this following section, we'll get to know a bit more about the location where we'll be doing our investigation.
Flood risk
Many factors affect flood risk. Some increase the risk of flooding, some decrease the risk. As revision, have a go at sorting these factors into those that increase or decrease flood risk in a catchment. There is a table to fill in in the hand out. If you find this a challenge, you may wish to review it before your visit:
Afforestation- planting trees within the catchment
Permeable soils and geology e.g. chalk or sandstone
Blocking moorland agriculture drainage channels (these are sometimes called grips)
Urban areas with impermeable surfaces e.g. tarmac car parks
Topography with steep gradients e.g. a mountainous catchment
Converting arable (crop) farmland to a wetland marsh area
Your investigation hypothesis
You may have some ideas now about what you expect to happen to Debden Brook as we go downstream and which factors may affect the flood risk. We will use your geographical knowledge about how rivers change along their long profile and the information you have about Debden Brook to decide on a hypothesis when you get to the field centre.
A hypothesis is like a prediction of what you think you will find in your investigation. You then collect data to test it and see if you can support a geographical idea.
To prepare for this, have a think now about how and why you expect drainage basin and channel characteristics to affect flood risk on Debden Brook and what you expect to see as you go downstream. Write 3 predictions in your handout.
