There could be some debate as to whether the Broads, as an area, really is man made. At what point in history should we refer to? There is a legal maxim on that & I really can't remember it, however, whilst the Broads themselves are probably 'man-made' in origination the rivers that flooded them were largely natural in their original state. Yes, tidal flows have been reversed in one case and in reality our rivers, as we know them, are largely the result of industrial intervention, the rivers being the motorway of medieval East Anglia, but at one point in history they were totally, unarguably natural. The Waveney for example, when there was a land-bridge to the continent, was, as I understand it, a tributary of the Rhine. The Broads are unique, even peculiar, they need to be understood as such, something the good Doctor has yet to appreciate, indeed he appears to have fought that reality from his very first day in authority. His quest to downgrade the Broads to lakes and just another national park are indicative of his mindset, for most along the rhond the Broads is the Broads, complete with its idiosyncrasies, legal or otherwise.