Salt‑water disposal into the Delaware Mountain Group (DMG) of the Permian Basin has prompted concern over pore‑pressure buildup and induced seismicity. The DMG consists of 1.2–1.4 km of fine‑grained siliciclastic strata capped by thick evaporites and serves as the principal interval for disposal of flowback and produced water. Because unconventional wells yield multiple barrels of water for each barrel of oil, cumulative disposal volumes reached 5.8 billion barrels by 2019, making this one of the world’s largest disposal systems. Previous modelling indicated that injecting this volume between 1983 and 2019 raised pressures by 100–400 psi, creating artesian conditions and highlighting the need to understand disposal impacts. The updated three‑dimensional hydrologic simulation extends the analysis to November 2024 using refined stratigraphy and an expanded disposal dataset. Calibration reproduces observed injection pressures. Results reveal regional pressure increases of 200–500 psi, with localised hotspots exceeding 500 psi, and show that the Bell Canyon formation experienced the largest pressure evolution. Pressure diffusion occurs laterally and vertically through interconnected sand units and may affect overlying aquifers. Production volumes are insufficient to relieve pressure. The study underscores the importance of pressure monitoring, adaptive injection strategies and water recycling to mitigate geomechanical hazards.