Fluid boundaries: erosion and accretion
A cursory glance at a map of the country’s coasts and rivers alludes to the huge number of properties which abut some form of waterway and will likely be subject to a boundary doctrine which has only grown more unpredictable in its application.
In acquiring a property bordering the coast or a river, conveyancers and developers will immediately consider the elevated flood risks and escalating insurance costs that can often come with such sites. However, this can overlook the potentially unstable nature of the property’s boundaries and their potential to change both gradually and abruptly through the dynamic and inexorable processes active in such areas.
Whether the immediate effects of these processes are detrimental or even beneficial, the legal doctrines governing the re-allocation of the natural “shifts” of land boundaries must be considered when deciding whether to acquire a property in immediate proximity to a waterway.
At one end of the spectrum is the well-known process of erosion with its most severe displays visible at various points along the Norfolk coast. The extent of it is highlighted by HM Land Registry’s MapSearch tool which reveals a number of property boundaries which already contain more sea than land. However, what is less well-known is its rarer counterpart “accretion” the process through which alluvial deposit of matter gradually increases the volume of land present.
The legal Doctrine of accretion and diluvion accepts the inevitable change of properties bordered by bodies of water and holds that, where such a change is gradual, the registered land boundaries will automatically adjust in reflection of land gained and lost by the adjoining properties.
When the change is sudden and dramatic, such as that induced by a violent flood, the Doctrine of avulsion states that the boundaries will remain as shown on the title documents. Although, one could argue that the ultimate effect of this rule on a landowner will likely be minimal since the floodwater eventually drains away, it is worth bearing in mind that floods do have the potential to permanently change the direction and size of watercourses. When conducting due diligence into a riverside or coastal property, the operation of these doctrines can be a crucial and potentially concealed factor where the Land Registry holds only older Title Plans, as section 61 of Land Registration Act 2002 states that the boundary shown in the register does not affect the doctrine’s validity meaning that potentially extensive swathes of land could have been eroded over the intervening decades. Yet it is worth conveyancers being aware that, under s61(2) LRA 2002, agreements concerning the operation of this doctrine can be registered at the Land Registry as a safeguard. In the absence of such protection, the acquisition of more recent aerial photographs of the site and a comparison against the older plan could provide important information regarding the historic and future changes that the site will undergo.
The unpredictable application of these doctrines highlights the potential for contention in waterway-abutting boundaries and the need for investigation into the physical changes undergone by such sites. A property’s vulnerability to erosion or other similar physical processes is an area that is distinctly absent from any Flood, Environmental or Ground Report that is typically encountered and, though only an issue in specific areas, it is an undeniable concern to have a regularly re-adjusted boundary.