In recent years, rapid population growth, agricultural expansion, climate change, and the decline in surface water resources have significantly increased the demand for groundwater in Iran. Combined with inadequate aquifer management, these factors have led to widespread land subsidence across most of the country's alluvial aquifers. In addition to reducing groundwater storage capacity and aquifer productivity, land subsidence poses serious risks to existing and under-construction infrastructure, particularly in areas experiencing high subsidence rates. Linear infrastructure, such as roads, highways, railway lines, and pipelines, is especially vulnerable because of its sensitivity to differential settlement between adjacent sections.

Given the extensive distribution of subsidence-prone areas in Iran and the ongoing expansion of the national railway network, traversing these areas has become unavoidable. One of the most challenging projects in this regard is the Tehran–Qom–Isfahan High-Speed Railway, which passes through two of Iran's most active and significant land subsidence zones, located south and southwest of Tehran and north of Isfahan. Accurate prediction of future land subsidence in these areas is therefore essential for both the design and long-term operation of the railway.

This study investigates the historical pattern of land subsidence along the entire 410-km railway corridor and provides a detailed assessment of the identified subsidence zones by examining groundwater resources, groundwater-level fluctuations, and projected future subsidence rates. The results indicate that, throughout its operational life, the railway will face considerable challenges in the subsidence-prone areas south and southwest of Tehran and north of Isfahan. Accordingly, appropriate engineering measures and risk mitigation strategies should be implemented to minimize the impacts of land subsidence and ensure the long-term safety and reliability of the railway infrastructure.