This shapefile represents the spatial distribution of mean annual water-budget components, in inches, for the island of Oahu, Hawaii for a projected future-climate condition representative of phase 5 of the Coupled Model Intercomparison Project (CMIP5) Representative Concentration Pathway 8.5 (RCP8.5) 2041-70 scenario climate and 2010 land cover, as described in USGS Professional Paper (PP) 1876 by Izuka and Rotzoll (2023). The water-budget components for each model subarea were computed for the future-climate condition and 2010 land cover using a water-budget model developed by Engott and others (2017). The 2010 land-cover map developed by Engott (2017) was used to define the land-cover conditions and the model subareas. The future-climate condition used statistically downscaled rainfall projections for mid-century 2041-70. The shapefile attribute information associated with each subarea (or polygon) present an estimate of mean annual rainfall, fog interception, irrigation, septic-system leachate, seepage from reservoirs and cesspools, runoff, canopy evaporation, total evapotranspiration, and groundwater recharge. This shapefile also includes select geographic and land-cover attributes of the model subareas. Brief descriptions of the water-budget components and attributes are included in this metadata file. Refer to Engott and others (2017) and Izuka and Rotzoll (2023) for further details of the methods and sources used to determine these components and attributes.