Monday, 1 July 2013

CE Fieldwork Guide: River Study

  • Rivers should change along their course from the source where they start to their mouth where they run into the sea.
  • The route of the river is known as its long profile.
  • Along the long profile (heading towards the mouth) the following changes should occur:
    • The amount of water flowing in the river (or discharge) should increase.
    • This often means that the Cross-Sectional Area (CSA) increases too: but be careful the river can be narrow but deep, or shallow but wide!
    • The stones on the bottom of the river, or the river’s bed load, should get smaller and rounder as you approach the mouth.



w = width
(measured perpendicular, at 90°, to the bank)

d = average depth
(measure the depth across where you measured the width at regular intervals and take an average)

CSA = Cross Sectional Area

v = stream velocity
(the speed that the water is travelling measured in metres per second - m/s; can be measured using a flowmeter or by timing a float as it travels a fixed distance a number of times and taking the average)

D = Discharge
(volume of water flowing in the channel; measured in cumecs or cubic metres per second – m3/s)

Some helpful formulae:

CSA = w x d

D = CSA x v


1. Hypothesis

This section should contain one or two sentences only.  These should be clear statements that you will be able to prove or disprove by carrying out the fieldwork.


Example: You could investigate how the river's Cross -Sectional Area, Discharge, Load, water quality Changes down stream. 


If you chose discharge, then your hypothesis might read ..

"The rivers discharge will increase along the rivers long profile"

 This can be proved to be true or false using the data you collect.

 2.  Method

This section should be no more than 100 words.


  • What equipment did you use? 
  • Describe how you collected the data.
    • How did you measure the river's width, depth and velocity? 
    • Why not try and use diagrams to help you ...


Example: Measuring the depth ...


...only neater !!!!!


  • Where did you collect the data?
    • Draw a location map and show which points along the river you collected data from.
    • Highlight any relevant local features on your map that might influence your data (ponds, dams, weirs, etc.)


3.  Results
  • This section should contain graphs that show information that is relevant to your hypothesis.

Example: If you are looking at how discharge changes from the source to the mouth ...

  • A set of graphs showing the cross-sections of each site (remember to keep the scales the same!)
  • A graph showing the discharge at each site.
  • Maybe a set of annotated photographs to show what the river looked like at each site: what its bed load and valley look like. (You will need one for Site 1 where there was no water!)


4.  Analysis

  • This is the most important part of the project!
  • Describe what each of your graphs show referring to the hypothesis statement:  Do they help to show that the statement is true or false?
  • If there are any unusual or any unexpected results on your graphs, highlight them and try to provide an explanation for these anomalies (unusual results).

5.  Conclusion and Evaluation

  • Have you proved you hypothesis to be true or false?  
  • How could you have made the results fairer? You should write about ...
  • The amount of data that you collected (remember the more that you collect, the fairer the results).
  • The accuracy of the data.  How could you have made the data collection more accurate and fairer?
  • Where you collected the data from. Would you have chosen the sites that were measured differently?  Why?
  • This section should be no more than 400 words.

6.  Appendix
  • This section should contain any information that you want to include in the write up but it is not appropriate to put it into the main project.
  • This section should include …
    • A neat copy of your raw data (see river data)
    • A bibliography.  A list of books and websites that you have used and referred to in your writing.
    • Any other relevant pieces of information.