The research was presented at the 9th Asia-Pacific Conference on Synthetic Aperture Radar (APSAR 2025), held in Matsue, Shimane, Japan on 04-10 October 2025. APSAR is a premier international event that focuses on advancing Synthetic Aperture Radar (SAR) technology and its applications, particularly within the Asia-Pacific region. The study investigates ground deformation during the early construction phase of the Metro Manila Subway Project (MMSP), the Philippines’ first underground mass transit system. Using the Persistent Scatterer Interferometric Synthetic Aperture Radar (PSInSAR) technique and Sentinel-1 satellite data, researchers analyzed line-of-sight (LOS) displacements from December 2022 to May 2025 along the CP101 section, including the stations of Valenzuela, Quirino, Tandang Sora, and North Avenue.
Over the 30-month observation period, the analysis showed that ground motion within the tunnel influence zone and surrounding areas followed similar trends, indicating minimal subsidence or uplift overall. Pre-construction measurements revealed comparable deformation rates, suggesting that tunneling activities have not significantly affected ground stability. The results highlight that the MMSP tunnels are located within a geologically stable corridor, reducing the risk of hazardous ground movement. Furthermore, the study demonstrates the value of PSInSAR as a high-precision, long-term monitoring tool for large-scale urban infrastructure projects. Continuous observation is recommended to ensure safety as construction advances, underscoring the critical role of advanced remote sensing in promoting sustainable urban development. By sharing these findings at APSAR 2025, the research contributes to global discussions on innovative geospatial technologies for infrastructure resilience.
