Ageing railway bridge which can be monitored using InSAR , with a satsense logo on the left bottom corner

Monitoring Rail Infrastructure Using InSAR



Monitoring Rail Infrastructure Using InSAR

With 9,876 miles of route and 2,578 stations, the UK’s rail sector managed 1,385 million passenger journeys in FYE March 2023. A significant increase of 39.9% over the previous year. In the same year, Network Rail, the rail operator in the UK, spent £2.1 billion on maintaining its assets. This was part of their total expenditure of £15.9 billion.

Operating and maintaining a large rail network requires continuous monitoring and investments around the year which costs dearly, both monetarily and in time. InSAR (Interferometric Synthetic Aperture Radar) not only reduces the time and cost of monitoring but also enables asset managers and engineers to monitor the entire network at scale with up to mm/year level precision. Let us look at a few other ways InSAR can benefit asset managers and engineers in the rail industry.

Wide area coverage and near real-time reporting

InSAR increases measurement coverage by providing thousands if not millions of data points depending on the size of the selected area, allowing engineers to monitor the whole rail network at scale. The data is updated after each satellite acquisition providing near-real-time reporting for the asset in question or wider network. The combination of wide-scale and near real-time monitoring enables a shift towards proactive, preventative maintenance, saving on expensive emergency remediation works.

This high-precision monitoring capability allows for early detection of potential problems and timely preventative measures. Infrastructure companies and engineering firms, amongst others, use InSAR data to monitor different assets such as commercial, and residential properties, large mining sites, entire road, and rail networks and even water utility networks.

Access to historic movement data over the asset and beyond the boundary fence

Traditional monitoring methods require manned surveys and in-situ equipment and provide movement data from the date of installation. InSAR data, on the other hand, provides both ongoing and historical movement data. This helps engineers build a comprehensive understanding of past movements and their impact on the surrounding area. By using InSAR alongside traditional monitoring methods, asset managers and engineers have a much better understanding of how the ground moved historically, and how it is moving in real-time, across both large and small areas.

Assessing the impact of ground movement outside of the right of way could be difficult. InSAR helps overcome this limitation because it can look beyond the boundary fence since it requires no installation on the ground. This helps asset managers to assess the impact of nearby landscape changes on the asset, that may have been missed with in-situ monitoring methods installed in a narrow rail corridor.

Enabling safe monitoring with reduced risks

InSAR data provides ground movement insights to mm/year precision. Thus, enabling geotechnical engineers to understand possible geological hazards with high accuracy. Early detection of such granular shifts in the ground mitigates safety risks for both passengers and personnel. SatSense's dataset also allows asset managers to pinpoint areas for priority maintenance, which results in optimal resource allocation with lower maintenance expenses and fewer boots on the ground.

Building machine learning models to better predict failures

SatSense’s advanced machine learning models can analyse large InSAR data sets and look for patterns to identify assets most at risk of critical failure. This helps asset managers direct proactive maintenance measures to key areas, preventing costly downtime and emergency remediation works. This ultimately improves passenger and infrastructure safety across the entire network.

Overcoming coverage challenges with corner reflectors

Whilst InSAR is a powerful tool, like other remote sensing techniques, the technology does have its limitations. InSAR works best in urban areas and rural areas with sparse vegetation. Densely vegetated areas pose much more of a challenge. To overcome this challenge, we can install corner reflectors.

A corner reflector helps by back-scattering radar waves to the satellite, enabling coverage in areas where there previously may not have been. Once installed, the reflectors are self-sufficient, require no electricity and are very low maintenance. This makes them a cost-effective solution to overcome this limitation.

InSAR as a complimentary technique

While InSAR has many advantages over traditional monitoring methods. It is best used as a complementary technique which ensures continuous remote data collection, helps analyse movements at both small and large scales, allows us to look beyond the boundary fence, and allows a company to prioritise areas for maintenance.

Different rail assets like bridges and rail corridors being monitored using InSAR, additionally there are corner reflectors on a densely vegetated site for enhancing coverage and red and green squares indicating how high-risk areas are highlighted using SatSense’s custom risk metrics

About SatSense’s InSAR solutions

SatSense is a leading provider of InSAR data and solutions. We’re changing how you access and interpret satellite ground movement data. Our mission is to make this once-expensive dataset affordable, accessible, and easy to interpret. We do this by providing high-quality InSAR data through our data visualisation portal; SatShop.If you would like to know more about SatSense’s InSAR solutions, please email us at or contact us here