Transport infrastructure monitoring uses Earth observation to find deformation, disruption, exposure, and visible damage along roads, railways, bridges, ports, and adjacent corridors.^[1]^[2]

InSAR is the strongest route for slow ground-motion risk: repeat SAR observations can measure millimetre-scale deformation along railway tracks and embankments, supporting routine monitoring where coherent scatterers are available.^[3]^[4]

Optical and SAR change detection serve the event-response side of the topic. They can map washouts, landslides, flood disruption, construction encroachment, and post-disaster access constraints, especially when combined with transport-network inventories.^[2]

EO does not replace engineering inspection. It prioritises sites for inspection by showing displacement trends, surface change, and exposure evidence that asset owners can combine with ground sensors, maintenance logs, and field crews.^[5]