That's not correct Peter - plenty of info on action by the government on dredging
here.
There was so much misinformation put out about dredging after the Somerset floods that the EA put out a leaflet explaining their position - I have a copy but can't upload a pdf here.
The EA dredged part of the Dour at Charlton Green about 4 years ago, getting rid of silt and profiling the river to provide a better habitat for the resident trout at the same time.
Edit - just realised I put a link to marine dredging there, now can't find the one I intended to put up but will keep looking!