Maps of the relative ease with which water can move to the water table can be used to guide planners to recognize where ground water is more or less susceptible to land-use activities which artificially recharge the aquifer (e.g. septic sewage disposal, drain wells, etc.).

This example of a preliminary vulnerability map, showing the relative ease with which water can infiltrate to the water table, was created with best available information on soil type and drainage characteristics, surface slope, depth to water, aquifer characteristics, and characteristics of soil and rock between the surface and the water table.

Although such maps are preliminary because the information upon which they are based is incomplete or insufficiently imprecise, they provide a general picture of the areas in the valley which are most and least vulnerable to surface impacts.