Yes, it is true the flooding in some parts of Somerset could be alleviated by dredging the rivers.
But.......
The larger truth is that 'we' have made an arse of building in places where 'we' should not without a thought for lots of rainfall and the 'what if' factor.
Houses have been built on historic flood plains and that's just plain stupid.
More importantly though I would ask you to consider this, in some way the Somerset levels and indeed significant parts of Norfolk, Suffolk and Hampshire have been/are an artificially controlled or man made environment pretty much since man learned to say more than "ug" or a few years later "watch out for the nasty bitey dinosaur". OK, I exaggerate a little, but certainly since Roman times (what have the Romans ever done for us
) 'we' have endeavoured to control our environment to improve agricultural yield or serve our purpose, this is patently evident in those counties and elsewhere if you car to look.
Controlled flooding of fields in Hampshire was a winter event as part of a managed water system, but this fell away post WW2.
When the husbandry of those environments is neglected, forgotten about or just simply abandoned there are bound to be consequences. That said, across Somerset and the likes of Norfolk and Suffolk, there have been significant historic flooding events that (by and large) the media chose to neglect to mention in their current report ("we're doomed Captain Mannering, we're all doomed") as obviously it's far worse now than it has been in the past.
That would be utter bollocks.
Fair play, on occasion, historic flooding has been more about coastal inundation flooding from the sea than flooding caused by precipitation but it would not be the first time that heavy rainfall combined with severe storm surge and high tides has caused significant 'backing up' of the low lying river systems and inland flooding.
It amuses/concerns me that in some ways folk in the south are saying that pumping will resolve this and the Environment Agency must take responsibility for this... and so on. Truth is if you don't manage and continue to look after something you've artificially created in the environment at some point nature will want it back, if you continually cut the budget of the body set up to look after the environment we have created what the hell do you expect to happen
Sorry Matt, I kind of went off on one there but, in my defence, it really pisses me off something chronic the way this is being reported.
I hope I answered your question.
H