Irrigation development has led many areas to depend upon mining of local groundwater for considerable proportions of their income. As groundwater depletion takes place these areas can develop alternative supplies, instigate economically advantageous transfers, or incur reductions in population and income because of migration. A conceptual economic model is presented for determining the appropriate combination of the alternatives for an area to use and the way in which the combination should be varied over time as the depletion continues. Little emphasis is placed on empirical findings for case study areas, however, some detailed work is presented on migration habits to be expected in Western Kansas. (Author)