The injected water migrates preferentially through high-permeability zones in both horizontal and vertical directions, creating regions of excessive water consumption characterized by low efficiency and ineffective recirculation. Developing a quantitative model to characterize water consumption rate and pinpoint high-consumption zones is vital for maximizing reservoir potential. To address the challenge of simultaneous oil, gas, and water coexistence post-degasification, this study redefines water consumption rate starting from its fundamental definition, integrates the impact of gas production via injection-production ratio adjustments, and computes water consumption rates for individual grids using cumulative water, oil, and gas flow rates derived from numerical simulations. This approach enables precise identification of high water-consumption belts. Field application demonstrates that these belts primarily form near fractured high-permeability wells. Implementation of measures such as separate-layer injection, stratigraphic supplementation, and profile control around “precise water injection and efficient water flooding” strategies reduced the natural decline rate from 6.5 to 5.0% and increased the predicted recovery rate by 1.9% points. Low-consumption zones located between high-consumption belts or at reservoir margins present opportunities for infill drilling. Since 2010, 24 infill wells deployed in Z reservoir's low-consumption zones achieved an average initial production of 13.1t/d within the first three months, validating the effectiveness of this methodology in guiding well placement. This approach leverages numerical simulation outputs while accounting for three-phase injection-production ratios post-degasification to accurately delineate high water-consumption zones.