The principle behind adverse possession is that you might acquire legal ownership of land by occupying it for 12 years or more.
Can this apply to a river, or rather the land underneath a river? A recent case has highlighted this interesting quirk in the law.
The Port of London Authority had applied to the Land Registry to register their title to part of the river bed and foreshore on a tidal stretch of the Thames. A Mr Mendoza objected, claiming that although the authority had paper title, he had acquired title to part of the river bed by adverse possession.
Mr Mendoza had lived on a houseboat which had continuously occupied the same mooring for the 13 years before the authority's application. Initially, the tribunal found that he had indeed acquired title to the rectangle of river bed beneath his boat through adverse possession. The authority then appealed and won on the basis that Mr Mendoza's actions had not shown sufficient evidence of an intention to take adverse possession of the river bed. Presumably, if Mr Mendoza had shown more clearly that he intended to possess the land, then he would have been able to claim ownership.
Before you start mooring your boat on local rivers and try to build a case for adverse possession, we've checked Land Registry records and the River Gade is registered land, as is the Grand Union Canal and Rickmansworth Aquadrome (but parts of the River Colne are not yet registered).
Landowners should actively manage their land to ensure that squatters do not acquire such rights. The law in this area is quite complex and the rules are different for registered and unregistered land.