Published Tue 20th May 2025
Why Slope Failures Are a Growing Threat to Infrastructure
Slope failures such as landslips and embankment failures cause damage, danger and disruption affecting roads, railways and other transport infrastructure.
The challenge is growing due to increasingly frequent and prolonged periods of extreme rainfall, ageing infrastructure, increasing traffic and the drive to keep “boots off ballast”.
The First Remote Landslip Monitoring System: A Turning Point for Network Rail
Remarkably, it is now a decade since the first wireless remote condition monitoring system to detect and warn of landslips was deployed on a Network Rail cutting at Barnehurst, South London. The system demonstrated its value almost immediately by warning of gradual ground movement three days before a large-scale landslip suddenly deposited tonnes of soil and debris on the track just before rush-hour trains were due on the route. Since then, the technology has been continuously improved and deployed on an industrial scale across many of Network Rail’s most “at-risk” sites, particularly on its Southern Route covering Kent, Sussex and Wessex.
Building a Smarter, Scalable Solution for Slope Monitoring
The journey that started with concept and trial deployments in 2015 has led to large-scale use of sophisticated integrated systems today. That journey involved many challenges, which would not have been overcome without a truly collaborative approach between an asset owner (Network Rail) and technology experts at Senceive. The result is a smart IoT solution that is easy to implement, provides reliable continuous monitoring of remote sites and requires minimal maintenance over its ultra-long (10 years-plus) life.
Key Milestones in the Evolution of Landslip Monitoring Technology
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the addition of first generation solar-powered cameras configured to send immediate site photos in the event of ground movement
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transition from IX tilt sensors to the Nano range
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Standardisation of a four-level alerting system based on the severity of the earthwork failure
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Upgrading to second, and then third generation camera systems which combine the camera and the communications gateway, automatically remove moisture from the lens, and have the processing power to generate clear images on the darkest nights without a flash or illuminator.
Slope Monitoring at Scale: 20,000 Tilt Sensors Across Southern England
Today a total of 20,000 tilt sensors and 1000 cameras are deployed on 50 kilometres of track in Kent, Sussex and Wessex alone. The same technology is being employed on a growing scale on other UK routes and in Germany, France and the USA.
Integrating Multiple Sensors for Comprehensive Earthwork Monitoring
The solution has matured into a robust, integrated package, with options to include other sensors as part of the same wireless network. Prime examples are soil moisture meters, weather stations and borehole piezometers.
Adapting Slope Monitoring for Rockfall and Flood Risk Applications
Most applications are intended to detect mass movement of soil, but it became clear that, with some modification, bespoke packages for different events could be provided. An example is a rockfall monitoring solution launched in 2024 where various wireless sensors can be attached to fences and barriers to detect and warn of material falling onto the fence potentially blocking the railway track or road below.
Another application is flood monitoring, where a combination of wireless instruments and cameras gather and compile critical data on rainfall, soil moisture, and water level. This provides asset managers with continuous data and real-time alerts to help manage the risk of earthwork failures and other disruptive events.
The Future of Wireless Monitoring for Landslip and Slope Stability
The future looks bright for wireless monitoring as the primary early warning technology for railway earthwork failures with further innovation in the pipeline, both from Senceive and from the various users. Just one such example is streamlining the alerting process such that messages are sent directly to signallers so they can react to potentially dangerous events without waiting for an assessment by geotechnical engineers.
