Flooding

Not sure I entirely agree. There are cases, where rivers are short and quickly reach the sea to say that regular dredging is helpful but on inland rivers dredging can exacarbate flooding. If rivers well inland are dredged so that water runs off the land into the river very fast the rush of water down the river can mean that communities downstream that previously never flooded can begin flooding.

A classic example of this was the flooding in Wraysbury and surrounding areas last year. The Thames had not been dredged but a flood relief channel was built south of Maidenhead to hasten the draining of water from the Maidenhead area. The result was when the channel was used following very heavy rain it ended with large areas of housing down stream being flooded that had never flooded before

The Environment Agency is now proposing to do something similar around Oxford and riverside communities east of Oxford are very concerned that the measures aimed at stopping Oxford flooding will result in them flooding instead as all the extra water is hastened down the Thames.

In the past meandering inland rivers, their courses full of weeds and tree roots, surrounded by water meadows, that were used for grazing rather than crops, slowed down the movement of excess water so that area below them were not flooded.

The main purpose of dredging at places like Cockermouth as referred to in the article was to keep harbours deep enough for shipping and the business it brought to the port, not to improve the running of rivers.

We are an island and not a huge continent and clearly one size does not fit all.
The fact that our forbears investigated the unique problems of our watercourses, legislated for a course of action and followed it to keep our homes safe, most assuredly indicates that this was given serious consideration and found to be the most effective action to take.

As Winston Churchill said, "Those who fail to learn from history are doomed to repeat it."

I think in the past, as now, if communities could find a way to solve their own problems they did not really care about the problems their solution might cause other people, such as communities further down stream.

Dredging was not a common way of controlling watercourses over much of the UK. Certainly in areas of land reclamation, like the Somerset levels and Lincolnshire Fens, straight ditches and dikes were built and rivers were straightened and regularly dredgedand embanked in order to get the water off the land and into the sea as quickly as possible, but outside these areas dredging for flood prevention was rare.

Big rivers like the Thames had their courses deepened and narrowed by the building of locks and embankments, but in almost all cases these were done to make the rivers navigable, not to prevent flooding, and often caused it.

In the past towns and villages were built on high land beside rivers so that they did not flood. It was only with the industrial revolution and the need to provide cheap housing for the flood of factory workers moving into towns that housing began to be built on the flood plains.

Flood prevention is a very complex subject. Climate changes that have lead to increases in the intensity of rain and the nature and frequency of flooding, land clearance for building or agriculture have all changed the situation. In some situations dredging may be helpful, as are flood protection bunds and walls, but often what is needed is to slow the passage of water through streams and rivers not enhance it by dredging.