The Northeast Frontier Railway (NFR) has ushered in a major technological shift in railway safety by deploying advanced Remotely Operated Robotic Vehicles (RORVs) for the underwater inspection of critical rail bridges throughout the region. This strategic initiative permits detailed structural evaluations of vital bridges where foundations are constantly submerged, ensuring the integrity of essential transport links. A key focus of this program was the historic Saraighat Bridge, India’s first rail-cum-road bridge and a crucial 1.45-kilometer connection across the Brahmaputra River between Pandu and Amingaon.
To conduct a comprehensive assessment, the NFR utilized the RORV surveys alongside a suite of modern digital assessment tools, including LiDAR, thermal imaging, Ground Penetrating Radar (GPR), and Ultrasonic Pulse Velocity (UPV) tests. This combined technological approach allowed engineers to thoroughly examine underwater scour zones, well foundations, pier caps, deck components, and superstructure stress points. The scope of the work also extended to the Alipurduar (APDJ) Division, where RORVs scanned eighteen important bridges. These robotic vehicles successfully captured high-resolution visuals of the submerged piers, riverbeds, and any potential hidden structural defects, with officials confirming that no major underwater issues were identified in any of the structures inspected.
The railway zone’s commitment to this advanced safety protocol is evident in its inspection figures, with thirteen bridges undergoing underwater assessments in the 2024–25 financial year, and an additional thirty-four bridges already covered in 2025–26. The substantial data collected through these surveys is significantly enhancing the accuracy of structural health monitoring, which facilitates more timely and effective preventive maintenance. The NFR emphasized that adopting RORV technology in tandem with other modern digital assessment tools represents a major leap forward in scientific bridge inspection methodologies. This underscores the railway’s unwavering commitment to boosting the safety and extending the longevity of its major bridges—especially critical assets like the Saraighat Bridge and other vital structures that guarantee uninterrupted rail connectivity across the entire Northeast.
