It is normal practice for a developer to construct a new road and then, once the works have been completed, to have this road adopted and maintained by the Highway Authority at the public expense.

The vehicle for facilitating such an arrangement is a Section 38 agreement, pursuant to the Highways Act 1980. Despite being commonplace, the recent case of KBC Developments LLP v Wavin Ltd & Anor [2023] EWHC 153 (Ch) has served as a stark reminder that such agreements are not always straightforward and highlights the importance of carefully checking the extent of the land that is to be adopted by the Highway Authority.

The facts

KBC Developments Ltd (‘KBC’) own land on one side of a railway line. They had obtained planning permission to build a bridge over the railway line, connecting their land to a recognised public highway called Parsonage Way. The dispute involved a strip of land connected to Parsonage Way, with the court being asked to consider whether this land could be considered as part of the public highway or whether it was privately owned. If it was part of the public highway, then KBC would require the consent of the Highways Authority to be able to construct the proposed bridge. If, however, it wasn’t part of the public highway and was in fact privately owned, then KBC would need the consent of the relevant landowner instead.

KBC were of the view that the strip of land was part of the public highway. However, Wavin Ltd (‘Wavin’), who owned the land either side of Parsonage Way, argued that it was not and therefore, KBC would need their permission to be able construct the bridge. Wavin’s reasoning was two-fold: (1) the horizontal plane argument and (2) the vertical plane argument.

1) The horizontal plane argument

Wavin had originally applied for planning permission in 1990 to be able to develop their land. The planning application (and accompanying plans / drawings), which included the proposal to have Parsonage Way adopted as a public highway, did not include the disputed strip of land. Wavin argued that this was evidence that the strip of land was never intended to become part of the public highway and that it was to remain under Wavin’s ownership. They therefore asked the court to consider the Section 38 agreement in light of the 1990 planning permission.

2) The vertical plane argument

Wavin also presented a ‘back-up’ argument in the event that the court did not give weight to the original planning permission in their decision making. They argued that even if the strip of land was considered to be part of the public highway, the airspace above it (for the purposes of accommodating the bridge) was not and therefore, their consent would be needed in any event.

The judgment

In respect of the horizontal plane argument, the court recognised that Wavin’s planning application (and the accompanying plans) did not include the strip of land as being part of the intended public highway. However, it rejected Wavin’s argument that the Section 38 agreement should be considered by reference to the planning permission alone and instead referred to the content of Section 38 agreement itself. Attached to the Section 38 agreement were a number of plans and drawings which did include the disputed strip of land as part of the road to be adopted as a public highway. One of the plans even included an annotation which identified the strip of land as “an area of land for possible future extension to Parsonage Way” to be dedicated by the relevant Highway Authority. Even though the agreement referred to the original planning application, it also included clauses which specifically stated that the highway works (that were later to be adopted by the Highway Authority) were to be carried out in accordance with the specific plans and drawings attached the agreement. It was on this basis that the court considered that the strip of land had been adopted as part of the public highway.

The court also rejected Wavin’s vertical plane argument, referring to the case of London Borough of Southwark & Anor v Transport for London [2018] UKSC 63 (‘Southwark’) and the ‘zone of ordinary use’. The Supreme Court in Southwark advised that not only does adoption of a highway include the surface of the road itself, but also the soil beneath it and the airspace above it, and that the extent of the space that this covers depends on the land in question. Wavin’s argument was that, to date, the disputed strip had only been used to accommodate users on foot, and therefore the extent of the airspace to be covered as part of the public highway should only include that which enabled the public to use the land in this way. However, the court recognised that the strip of land was never intended to only be used on foot and that there had always been the intention that it would form a connecting point with the proposed bridge if and when it was built, in accordance with the annotations on the plans and drawings attached to the Section 38 Agreement.

Therefore, the court concluded that the strip of land and the airspace above it was part of the public highway as set out in the Section 38 Agreement. KBC would therefore only need the consent of the Highway Authority to build the proposed bridge.


This case serves as a reminder to landowners, developers, and lawyers of the importance of ensuring Section 38 agreements (and their accompanying plans and drawings) are carefully considered and that all parties understand the extent of the land that will be subject to such agreements. Failure to do so can lead to uncertainty, the risk of litigation and the potential for a landowner to give away more land than originally intended.

TLT has extensive experience in advising on planning matters. If you would like to discuss any point arising from this article, please get in touch.

This publication is intended for general guidance and represents our understanding of the relevant law and practice as at May 2023. Specific advice should be sought for specific cases. For more information see our terms & conditions.

Written by

Katherine Evans

Katherine Evans

Date published

18 May 2023


View all