A WATERSHED-BASED SUMMARY FIELD EXERCISE FOR AN INTRODUCTORY HYDROGEOLOGY COURSE

As hydrogeology has become an established part of geoscience curricula, field coursework in hydrogeology has proliferated to include summer field courses, hydrogeology modules within conventional geology field camps, and monitoring of well fields and watersheds as part of regular courses. However, not all students can take summer field courses, and not every program has opportunities for appropriate field exercises close to campus.

Since 2000, we have conducted a summary field exercise for an introductory hydrogeology course without a laboratory section. During one day in April, students measure hydraulic heads, stream and spring flow, and stream-bed seepage within the rural watershed of Ledbetter Creek, a perennial stream in western Kentucky. Students calculate specific discharge (groundwater flux) at various scales, map groundwater flow in the watershed, and calculate vertical hydraulic gradients at the mouth of the watershed, where the creek enters a reservoir (Kentucky Lake). Distinctive features of the exercise include hydraulic head measurements in large-diameter domestic wells and in piezometers installed in the reservoir embayment. Kentucky Lake is raised ~ 2 m shortly before the field trip, thus providing an analog of bank storage.

This exercise builds on lectures and problem sets that use pre-existing field data. It focuses on groundwater/surface-water interactions, a commonly underemphasized topic in hydrogeology classes. It addresses concepts and skills, including measurement of hydraulic heads and mapping of groundwater flow, that are fundamental to hydrogeologic research and professional practice. Students engage in hands-on collaborative learning while interacting with local stakeholders (residents whose wells are monitored). Former students who responded to a questionnaire indicated that the exercise was worthwhile. The techniques and materials used in this exercise are broadly transferable to other times of year and other locations, including natural lakes.