Engineering Geology Considerations for Specifying Dam Foundation Objectives

In dam construction, the actual depth to adequate foundation materials at a site is known with certainty only at the points of exploration. The foundation objective serves as a descriptive tool to convey design intent information to construction engineering staff and the contractor. The selection of the most effective approach, or approaches, usually depends on site geology and the amount of available geologic and geotechnical data developed by the site investigation. The engineering geologist should be aware of the relevant approaches for defining a foundation objective prior to the initial site reconnaissance, so the subsurface site investigation can be designed to yield sufficient and meaningful information. This paper summarizes the various ways in which a foundation objective can be described.