Using the results gathered from a recent field study at the The Leigh Brook, suggest the morphological, hydrological and sediment differences between the Pool and Riffle.
Within a river there are areas known as pools and riffles. The pool is an area of deeper slow moving water, whereas the river is an area of shallow, fast flowing white water. The rocks are also clearly visible at the riffle, but submerged in the pool. A pool is usually found on a meander whereas the riffle is normally seen on the straighter areas of the channel, they tend to be situated very close to one another, forming in sequences. The aim of this investigation is to carry out a field investigation at a pool and riffle and compare the characteristics at these two sites with the objective to state the differences.
Site DescriptionThe river used for the investigation is a tributary of the River Teme , and known as The Leigh Brook. The River Teme is tributary of The River Severn. The site that was investigated lies in the Knapp and Papermill Reserve, managed by the Worcestershire Wildlife Trust.
MethodUsing a tape measure, measure the distance from right bank top to left bank top. Using a peg secure the tape measure in this position. Using another tape measure place it along the river bed from right waters edge to left. This gives the measurement for the wetted perimeter. Using a quickset level note the waters edge and both bank tops. Divide the channel by 3 and using a quickset measure the water surface at these points. At these sites measure the channel bed and water surface 1m downstream and 1m upstream. Next divide the channel by 10 and at each point measure the total water bed, distance across the channel and the velocity. Velocity is measured…
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