Primrose wrote:..., they are very interesting pictures of the dredging. Can somebody answer a question please? If the river level gets very high again, won't all the earth and sludge on the bare open banks merely be washed straight back into the water again, especially when it is flowing rapidly?
That is a good question Primrose. The answer is luckily no, the level of the river rises twice a day due to the Bristol Channel which has the second highest rise and fall of any sea on the Planet of 43 feet or 13 metres. As the river flows out to the sea it meets the incoming tide which in turn over comes the river's flow and a tidal bore results (similar to the River Severn Bore). The river Parrett is thick with silt and the banks are made from this heavy silt. When they dredge and cut the silted banks back they also smooth the surface of the bank to give a surface like putty so the bank holds its shape. This is a picture of the river taken recently, from where I graze my cattle, when the tide is in.
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As you can appreciate in the winter when the rain drain from the surrounding hills into the river it does not take much for the banks to overflow. The problem is once the banks (which are very high) overflow then it is extremely difficult to move the water back and massive pumps have to be used to effect the drainage. This is why it is imperative to regularly dredge the rivers. The area of the Somerset Levels and Moors is extremely rural and has always flooded each winter (in order to protect the towns) and for many years those in power thought it good for wildlife to continue allowing it to flood but the floods of recent years have been totally unacceptable. The area will still flood (it always has) but hopefully not to the extent that whole villages are cut off many months.
