Network Rail Wales and Borders is rolling out an innovative rail treatment programme across more of North Wales after a successful trial on the Conwy Valley Line eliminated leaf-related delays during autumn operations.
The expanded programme follows encouraging results from a trial between Tal-y-Cafn and Blaenau Ffestiniog, where no slippery-rail incidents or associated delays were recorded during autumn 2025. This compares with six incidents and almost 500 minutes of delays experienced in 2024.
The initiative centres on Interflon Leaf Guard, a specialist rail treatment designed to tackle one of the railway industry's most persistent seasonal challenges: low adhesion caused by leaf contamination.
Addressing a Major Autumn Performance Challenge
While "leaves on the line" can often sound trivial, the issue presents a significant operational challenge for railway operators. When fallen leaves are crushed onto damp rails by passing trains, they create a hard, slippery coating that can dramatically reduce wheel-to-rail adhesion.
The resulting loss of grip can affect train acceleration and braking performance, leading to delays, operational disruption and potential timetable impacts.
Interflon Leaf Guard is sprayed directly onto the railhead, penetrating the microscopic surface of the steel and breaking down residue left by fallen leaves. The treatment is reapplied every seven days throughout the autumn period to maintain effectiveness and prevent contamination from building up.
The treatment programme complements existing autumn mitigation measures, including Rail Head Treatment Trains (RHTTs), which clean rail surfaces across the network.
First Network Rail Route to Deploy Automated Application Technology
A key element of the programme's success has been the introduction of a new computer-controlled application system developed jointly by Network Rail Wales and Borders and its supply chain partners.
Known as RRV-SMART, the technology is mounted on a specially adapted road-rail 4x4 vehicle capable of operating both on highways and railway infrastructure.
Travelling at approximately 10mph, the system continuously monitors vehicle speed and automatically adjusts the volume of treatment applied to the rails, replacing the previous manual spraying method.
The automated approach delivers more precise and consistent application while enabling maintenance teams to target known low-adhesion hotspots more effectively.
The technology has been developed through a collaboration between Network Rail Wales and Borders, Fitzgerald Plant Services, Interflon Ireland and JCP Engineering Ireland.
Data-Led Approach with Transport for Wales
Network Rail is now working alongside Transport for Wales (TfW) to analyse wheel-slip data collected from trains operating on treated sections of railway.
The information will help engineers evaluate the effectiveness of the treatment programme, understand how it performs alongside other autumn interventions and determine whether wider deployment across the network could deliver additional operational benefits.
As a result of the successful initial trial, the programme has now been extended to the North Wales Coast Line between Conwy and Anglesey.
Around 650 cumulative treatment miles are planned over a 12-week autumn and winter campaign, targeting locations historically affected by significant leaf-fall related adhesion problems.
AI-Powered Track Monitoring Also Under Trial
Alongside the leaf-fall initiative, the same road-rail vehicle is being used to test new infrastructure monitoring capabilities.
Working with technology specialist One Big Circle, Network Rail has adapted the company's AiVR Focus line-scanning camera system into a portable deployment platform.
The system captures detailed imagery of track and lineside infrastructure as the vehicle travels across the network, helping engineers identify defects, hazards or obstructions more quickly.
The trial will assess whether the technology can provide additional inspection coverage on routes that are not routinely monitored by dedicated inspection trains.
Industry Reaction
Daniel Booth, Head of Operational Weather Strategy at Network Rail Wales and Borders, said:
"Leaves on the line might sound like a minor problem, but they can make the rails very slippery and cause significant disruption for passengers.
"That's why we're always looking for new ways to prevent problems before they affect services.
"Last autumn, we recorded no leaf-related delays on the Conwy Valley Line, compared with almost 500 minutes the previous year. While there are a number of factors that can affect conditions on the railway, these early results are extremely encouraging.
"What makes this particularly exciting is that we've worked with our supply chain partners to pioneer a completely new way of applying the treatment, becoming the first route in Network Rail to introduce this computer-controlled technology.
"We're now expanding the programme across more of North Wales, while working closely with Transport for Wales to better understand its effectiveness.
"By combining new technology with our established autumn preparations, we're finding smarter ways to tackle known problem areas, reduce disruption and help keep passengers moving safely and reliably."
If the expanded North Wales programme delivers similar results this autumn and winter, Network Rail will consider introducing the technology across other parts of the Wales and Borders route.
Image & Video credits: Network Rail
