Over the course of two days at the beginning of June, all five of the Year 10 GCSE Geography classes tackled an exciting adventure and overcame a series of challenges in order to complete our physical Geography investigation of the River Darent and learn how the river’s features contrast as we move downstream.
But what did we actually investigate? In the lessons building up to the trip, we received booklets which gave us sections for us to fill out with key information for the data we collected. This information included measuring the width and depth of the channel, the river velocity, the sediment size and the shape (all at each of the five sites). We did this in order to see if we could prove, or disprove, the Bradshaw Model and our hypothesis we made preinvestigation. This model stated that velocity should increase as we go downstream from source to mouth, channel width and depth should also increase, and the channel width it was as simple as holding a tape measure from one end of the bank to the other! Although sounding simple, keeping the tape measure taut was somewhat a mission in itself for some (including me!).
Measuring the depth was a much more difficult task as we had to make sure the metre stick was not lodged into the surface bed of the river, so that accurate measurements could be taken (I may have also snapped a metre stick in half due to the strong current!). To calculate the velocity of the river we used two people that were 5m apart from one another and timed how long it would take for a wooden block to get to the other person. Once nine values were gathered (three from the left, middle and right) they were inputted into the formula speed = distance/time. By doing this, it allowed for us to calculate the average velocity at each site and compare them to each other. In terms of sediment size and shape, 15 rocks were randomly sampled from each site (five from the left, middle and right!), and measured using a basic 30cm ruler. (Channel width and depth being measured) As a collective we learnt a lot about not only this river, but rivers in general. Safety precautions should always be taken in order to make the journey not only enjoyable but also successful!
Talking of successful I would say that some areas of our results matched up brilliantly with our hypothesis but unfortunately some did not. Reasons for this include human error (e.g. reaction time, not randomly sampling the rocks), lack of time (maybe if more time was spent at each site then more accurate and reliable results could have been taken. (My group and I all took part!)
All in all, the overall experience was incredible and indisputably an unforgettable one and thank you to our incredible Geography Department for organising this amazing trip! Our hypothesis question of, ‘How does the River Darent change downstream along its course?’ was certainly answered!
Taran Phagura (10Z2 Geography)