Familiar Fieldwork - Physical

Title

to investigate downstream change on the River Chess

Hypothesis

The discharge will increase with distance downstream on the river

Location - Where did you go and why?

We went to the River Chess, near Amersham to complete a River study of the river chess. the stream is easily accessible for students at 3 points and was shallow enough to stand in the flow to complete the measurements that we needed.

Risks

Uneven ground, weather hazards (hear), deep water, weils diseases

Method - Width of channel

The width of channel was measured by using a tape measure and holding it on either bam, one person read the width and another noted it down.

Method - depth of channel

Depth of channel was measured by measuring the width of the river channel and dividing it in 10 so that there were 10 equal measurements of the depth. At each location the meter ruler was placed on the river channel floor and the height of the water was measured on the ruler and was written down.

Method - Velocity

Velocity was measure using a hydroprop which is a velocity measuring device. We placed this into the river carefully pacling it onto the river bed. The impeller had to face into the flow. We then timed the amount of time it took the impeller to travel from the top of the hydroprop to the bottom of the thread using a stop watch. We then recorded that on our worksheet. We recorded velocity on the left, middle and right of the channel.

Evaluation of data collection - width of channel

The width of channel changes depending on the depth of water so if we measured it twice on different days we could have gained a more representative river width. Sometimes the tape measure is twisted or was not pulled tight enough by the people recording it. We needed to make sure that the people with this job were being more consistent with their method.

Evaluation of data collection - depth of channel

Measuring the depth 10 times enabled an accurate data collection method. We tried to make sure that we did not dig the ruler into the sediment on the bottom of the river, but this might not have been always the case. Sometimes people walked in front of the people recording the depth which may have altered the depth by them displacing the water

Velocity

we measured the velocity 3 times which made it an accurate recording of data but if we could have made 10 recordings it would have been even more accurate

Evaluation of data presentation

We used a line graph to show the change in velocity, width, depth of the river channel. It was easy to compare each location to see the changes and it was easy to measure specific numbers on the scale