From my own experience in London I believe that you are being unfair to a number of very hard working people. With regards to Barge moorings in the South East the local IWA, mainly in the form of the late Mike Stevens, put an amazing amount of work in when the Downings Road barge moorings campaign on the Thames when they were under threat. We are/have been very vocal in getting resources from BW and the Lower Lea Project to sort out the weed problems on the Lea and the Bow Back Rivers.
Tim