PLA v Mendoza  UKUT 146 (TCC), 24 November 2016.
The boat in question in this case was called the Wight Queen and was moored without engine or wheelhouse on the North bank of the Thames not far from Kew Bridge. It was owned and lived in by Mr Mendoza. On 16 November 2009 the Port of London Authority (PLA) applied to the Land Registry for first registration of its title to part of the bed and foreshore of the River Thames between Kew Bridge and Brentford Ait.
A number of people including Mr Mendoza objected. In a decision of the First Tier Tribunal dated 7 January 2016, the Tribunal found that Mr Mendoza had indeed acquired title by limitation to a part, though not the whole, of the area that he was claiming. The PLA appealed to the Upper Tier Tribunal. Judge Elizabeth Cooke gave Judgment for the Upper Tribunal and stated:-
66. The presence of a moored boat is as equivocal an act of possession as can be imagined. The casual observer, and likewise the paper owner, can know nothing of the boat owner’s intention from the boat’s presence. It is not possible to tell how long it has been there, how long the owner intends to stay, whether it is moored in exercise of an easement or of a public right, whether it is acquiring an easement, whether it has a licence to moor, or whether it is just trespassing, for a few days or a few months. As Mr Stoner QC [for the PLA] put it in his skeleton argument, “it cannot be that, without more, every person who moors their vessel up and down the River Thames is to be taken to have the intention to possess the land under and around the vessel”.
81. In this case, therefore, had Mr Mendoza been able to establish not only factual possession but also intention to possess I would not have found that the public’s right of navigation – undisturbed in fact by the Wight Queen’s presence would have made any difference to that. The analogy with the public highway breaks down because highways – which have to be completely open to traffic and pedestrians – are so very different from rivers.
The appeal by the PLA was, therefore, successful but the case makes it clear that a boatdweller could obtain adverse possession of the piece of the riverbed above which they have their vessel moored.
The previous case of R (Smith) v The Land Registry  EWCA Civ 200 seemed to indicate that it was impossible to acquire land by adverse possession if that land was subject to a public highway. However there is a possibility that this issue could be revisited in light of the judgment in the Mendoza case – what if the adverse possessor was not actually obstructing the highway at all (e.g. on the edge of a very wide highway verge, for example).
TAT represented Mr Smith in the above Court of Appeal case.