Spatiotemporal Risk Intensification from Encroachment on Underground Oil Pipelines: A Proximity-Based Indexing Approach

Rapid urbanisation and unplanned development in Africa have intensified encroachment on oil pipelines, heightening risks of leaks and environmental contamination. In Savelugu, fragmented governance and permit violations have eroded oil pipeline safety buffers. While frameworks like the U.S. PHMSA’s HCA offer static risk benchmarks, dynamic spatiotemporal assessments remain underdeveloped. This study developed and applied a Proximity-Based Risk Index (PBRI) to quantify encroachment trends along an oil pipeline, addressing gaps in synthesising proximity metrics with temporal risk intensification analyses. Multitemporal satellite imagery (2008–2024), pipeline vector data from Ghana’s BOST, and field-validated infrastructure coordinates were analysed using QGIS software. Euclidean distance metrics classified risk zones based on PHMSA’s PIR. Temporal trends were assessed via Mann–Kendall tests, Sen’s slope estimator, and Bai–Perron breakpoint analysis, while KDE mapped encroachment evolution. Infrastructure within HRZ surged by 545% and MRZ by 350% from 2008 to 2024. PBRI escalated from Low to Moderate, driven by declining mean proximity distances (HRZ: 31.34 m to 27.65 m). A significant positive monotonic trend (Kendall’s τ = 0.959, *p* < 0.0001) and Sen’s slope (0.268 units/year) confirmed accelerating risk. Structural breakpoints (2012, 2016, 2020) revealed phased intensification, correlating with urban expansion and regulatory shifts. KDE highlighted clustering along central and northern pipeline segments. These findings underscore urgent needs for enhanced land-use planning, periodic encroachment monitoring, community sensitisation on permit compliance, and GIS-enhanced regulatory enforcement. The PBRI’s methodology offers a replicable model for data-scarce regions. Future work should integrate socioeconomic surveys and real-time remote sensing to optimise risk mitigation.